Edelbrock Heads & Mechanical Fuel Pumps...
August 19th, 2012, 08:58 AM
#1
Registered User
Thread Starter
Join Date: Aug 2010
Location: Southington,Connecticut
Posts: 970
Edelbrock Heads & Mechanical Fuel Pumps...
Has anyone here used a RobbMc fuel pump with ebrock heads? Can the heads be machined enough to accommodate this pump?
What are some other mechanical fuel pump options?
What are some other mechanical fuel pump options?
August 19th, 2012, 09:47 AM
#2
Registered User
Join Date: Jul 2011
Posts: 488
I am running a Holley mech pump with my Edel heads, and it fits fine after a little work with a rotary file/Die grinder!
August 19th, 2012, 10:25 AM
#3
Registered User
Join Date: Sep 2010
Location: Shorewood, Il.
Posts: 3,057
On the heads, pump, or both?
August 19th, 2012, 11:07 AM
#5
Registered User
Join Date: Feb 2009
Location: West Hartford, CT
Posts: 1,422
Steve - pm me w/ your email, I'll send you photos of what has to be done on sbo. Maybe you could post them so people can see. BBO would be less relief needed.
August 19th, 2012, 11:10 AM
#6
Registered User
Join Date: Jul 2011
Posts: 488
I can post pics of mine when I get the car back, it might be tue or wed
August 19th, 2012, 12:36 PM
#7
Registered User
Join Date: Apr 2011
Posts: 2,703
What is it about an electric pump that makes people shy away from them? No way I would cut up a $2,000 set of heads so that I can use a mechanical fuel pump. So what if it says it supports 550 HP or 1100 HP...so do the electrics. And with an electric I don't have to crank the engine over to get fuel pumping up to the carburetor.
If you're going Edelbrock heads, might as well go electric fuel pump...you will have to do the same stuff to run a RobbMC as you will to run an electric. The only difference is a few more fittings and 2 wires to the pump. Anyway, I'm glad I did it, life is so much easier.
If you're going Edelbrock heads, might as well go electric fuel pump...you will have to do the same stuff to run a RobbMC as you will to run an electric. The only difference is a few more fittings and 2 wires to the pump. Anyway, I'm glad I did it, life is so much easier.
August 19th, 2012, 12:46 PM
#8
Registered User
Join Date: Jul 2011
Posts: 488
What is it about an electric pump that makes people shy away from them? No way I would cut up a $2,000 set of heads so that I can use a mechanical fuel pump. So what if it says it supports 550 HP or 1100 HP...so do the electrics. And with an electric I don't have to crank the engine over to get fuel pumping up to the carburetor.
If you're going Edelbrock heads, might as well go electric fuel pump...you will have to do the same stuff to run a RobbMC as you will to run an electric. The only difference is a few more fittings and 2 wires to the pump. Anyway, I'm glad I did it, life is so much easier.
If you're going Edelbrock heads, might as well go electric fuel pump...you will have to do the same stuff to run a RobbMC as you will to run an electric. The only difference is a few more fittings and 2 wires to the pump. Anyway, I'm glad I did it, life is so much easier.
On the other hand I can get out a die grinder, roatry file, 1-1/2 minutes have the proper clearence, slap on a polishing bit, 4 more minutes and be done.
A mechanical pump in most cases will be more reliable than an electric. Its all in what you feel comfortable doing but for me about 10 minutes worth of work for a more reliable set up is a no brainer. For me its not a matter of a pump supporting 1100 hp, its a mattter of what makes more sense.
Last edited by real57vetteguy; August 19th, 2012 at 12:50 PM.
August 19th, 2012, 12:56 PM
#9
Registered User
Join Date: Aug 2007
Posts: 2,250
I do not like running rubber lines nor hose clamps on fuel lines or transmission lines, so for me to run a elec pump I will have to cut and flare the lines, grab some fittings or have lines made up, run sheilded wires to the back, drill the frame to properly secure the wiring, heak shrink, solder, mount the pump etc etc etc.
On the other hand I can get out a die grinder, roatry file, 1-1/2 minutes have the proper clearence, slap on a polishing bit, 4 more minutes and be done.
A mechanical pump in most cases will be more reliable than an electric. Its all in what you feel comfortable doing but for me about 10 minutes worth of work for a more reliable set up is a no brainer. For me its not a matter of a pump supporting 1100 hp, its a mattter of what makes more sense.
On the other hand I can get out a die grinder, roatry file, 1-1/2 minutes have the proper clearence, slap on a polishing bit, 4 more minutes and be done.
A mechanical pump in most cases will be more reliable than an electric. Its all in what you feel comfortable doing but for me about 10 minutes worth of work for a more reliable set up is a no brainer. For me its not a matter of a pump supporting 1100 hp, its a mattter of what makes more sense.
August 19th, 2012, 01:02 PM
#10
Registered User
Join Date: Jul 2011
Posts: 488
re
I have had several electric pumps fail, but never a mechanical!
August 19th, 2012, 01:07 PM
#11
Registered User
Join Date: Apr 2011
Posts: 2,703
Just hope you don't go into the water jacket. And did you not install a larger pickup in your tank? Steve is building a 450 - 475 hp engine...what is yours? If it's that or more and all you did was install a RobbMC pump I'm afraid you are probably robbing yourself some power.
It's called a fuel system for a reason, and slapping a larger pump on a stock system is the same as throwing a huge cam at a stock low compression engine. It all works together. You can use the stock 3/8" steel fuel line with a AN to tube adapter fitting and plumb the rest with steel braided hose. Anyway, maybe 10 minutes worth of work to slap on a pump is worth it to you, but after all you've got invested in the engine and car I figure a little more work for a competent system is worth it.
It's called a fuel system for a reason, and slapping a larger pump on a stock system is the same as throwing a huge cam at a stock low compression engine. It all works together. You can use the stock 3/8" steel fuel line with a AN to tube adapter fitting and plumb the rest with steel braided hose. Anyway, maybe 10 minutes worth of work to slap on a pump is worth it to you, but after all you've got invested in the engine and car I figure a little more work for a competent system is worth it.
August 19th, 2012, 01:37 PM
#12
Registered User
Join Date: Jul 2011
Posts: 488
Just hope you don't go into the water jacket. And did you not install a larger pickup in your tank? Steve is building a 450 - 475 hp engine...what is yours? If it's that or more and all you did was install a RobbMC pump I'm afraid you are probably robbing yourself some power.
It's called a fuel system for a reason, and slapping a larger pump on a stock system is the same as throwing a huge cam at a stock low compression engine. It all works together. You can use the stock 3/8" steel fuel line with a AN to tube adapter fitting and plumb the rest with steel braided hose. Anyway, maybe 10 minutes worth of work to slap on a pump is worth it to you, but after all you've got invested in the engine and car I figure a little more work for a competent system is worth it.
It's called a fuel system for a reason, and slapping a larger pump on a stock system is the same as throwing a huge cam at a stock low compression engine. It all works together. You can use the stock 3/8" steel fuel line with a AN to tube adapter fitting and plumb the rest with steel braided hose. Anyway, maybe 10 minutes worth of work to slap on a pump is worth it to you, but after all you've got invested in the engine and car I figure a little more work for a competent system is worth it.
If that was directed to me then to answer your questions/comments.
1) The head needs to be ground on the lower corner, if you decide to take a side grinder to it and take about 1/2 inch or more out Im sure you will be successful in hitting a water jacket, there is very little that needs to be taken out to gain proper clearence.
2) Im running a new tank and pickup in mine
3) My engine is a 455 .40 over, 10:1 compression, crank ground, cut and balanced, Dick Miller ported edelbrock heads, Ported Edel intake, Custom grind cam by Cutlass EFI 228/232 568/568, headers, full magnaflow exhaust.
4) I never said it took 10 minutes to "SLAP ON A PUMP", I said "1-1/2 minutes have the proper clearence, slap on a polishing bit, 4 more minutes and be done"
5) My fuel system is comprised of 3/8 line, a holley pump, new tank and new pickup. I have plenty of fuel to support my build, I am actually going with a Prosystems 830 carb this week and I have plenty of fuel to supply that. Most of your common issues with a mechanical system not supplying enough fuel (within reason) is not the line size its the fittings used, I used all AN fittings which will flow much better than traditional brass barb type fittings, they are very restrictive. So what your stating is that my fuel system isnt complete or competent because I am not running an electric pump?
There are plenty of 500-600 HP cars running 3/8 line and a mechanical pump. I value your opinion and take every ones point of view into consideration but it seems right now your reaching for the stars as there really is no supporting arguement that he needs to upgrade his entire fuel system for a 450-475 HP engine.
August 19th, 2012, 01:54 PM
#13
Registered User
Join Date: Apr 2011
Posts: 2,703
Its unclear who your talking to?
If that was directed to me then to answer your questions/comments.
1) The head needs to be ground on the lower corner, if you decide to take a side grinder to it and take about 1/2 inch or more out Im sure you will be successful in hitting a water jacket, there is very little that needs to be taken out to gain proper clearence.
Ok, the Holley pump you have is NOT the RobbMC pump the OP is inquiring about. The Holley is not as big of a body as the RobbMC and does not take as much clearancing...
2) Im running a new tank and pickup in mine
If you read my recommendations for a fuel system it included pickup, pump, and some fuel line in addition to the stock steel line. So you have MORE than what I recommended, which is why you feel like you have enough fuel for your build.
3) My engine is a 455 .40 over, 10:1 compression, crank ground, cut and balanced, Dick Miller ported edelbrock heads, Ported Edel intake, Custom grind cam by Cutlass EFI 228/232 568/568, headers, full magnaflow exhaust.
You think you have enough fuel...put on a set of slicks and take it down the track. I bet you'll change your mind. That Holley sucker pump is going to lose about 3.5 psi on your launch and won't ever catch up by the end of the 1/4 mile. So what you think is good for the street isn't really good when it comes down to maximizing your performance...which, if you read my last post is why I suggest using an electric pump. You put all that money into your engine, just to starve it of fuel? Give it all it wants and it'll wake up, I promise you.
4) I never said it took 10 minutes to "SLAP ON A PUMP", I said "1-1/2 minutes have the proper clearence, slap on a polishing bit, 4 more minutes and be done"
Ok, 5 1/2 minutes then.
5) My fuel system is comprised of 3/8 line, a holley pump, new tank and new pickup. I have plenty of fuel to support my build, I am actually going with a Prosystems 830 carb this week and I have plenty of fuel to supply that. Most of your common issues with a mechanical system not supplying enough fuel (within reason) is not the line size its the fittings used, I used all AN fittings which will flow much better than traditional brass barb type fittings, they are very restrictive. So what your stating is that my fuel system isnt complete or competent because I am not running an electric pump?
There are plenty of 500-600 HP cars running 3/8 line and a mechanical pump. I value your opinion and take every ones point of view into consideration but it seems right now your reaching for the stars as there really is no supporting arguement that he needs to upgrade his entire fuel system for a 450-475 HP engine.
If that was directed to me then to answer your questions/comments.
1) The head needs to be ground on the lower corner, if you decide to take a side grinder to it and take about 1/2 inch or more out Im sure you will be successful in hitting a water jacket, there is very little that needs to be taken out to gain proper clearence.
Ok, the Holley pump you have is NOT the RobbMC pump the OP is inquiring about. The Holley is not as big of a body as the RobbMC and does not take as much clearancing...
2) Im running a new tank and pickup in mine
If you read my recommendations for a fuel system it included pickup, pump, and some fuel line in addition to the stock steel line. So you have MORE than what I recommended, which is why you feel like you have enough fuel for your build.
3) My engine is a 455 .40 over, 10:1 compression, crank ground, cut and balanced, Dick Miller ported edelbrock heads, Ported Edel intake, Custom grind cam by Cutlass EFI 228/232 568/568, headers, full magnaflow exhaust.
You think you have enough fuel...put on a set of slicks and take it down the track. I bet you'll change your mind. That Holley sucker pump is going to lose about 3.5 psi on your launch and won't ever catch up by the end of the 1/4 mile. So what you think is good for the street isn't really good when it comes down to maximizing your performance...which, if you read my last post is why I suggest using an electric pump. You put all that money into your engine, just to starve it of fuel? Give it all it wants and it'll wake up, I promise you.
4) I never said it took 10 minutes to "SLAP ON A PUMP", I said "1-1/2 minutes have the proper clearence, slap on a polishing bit, 4 more minutes and be done"
Ok, 5 1/2 minutes then.
5) My fuel system is comprised of 3/8 line, a holley pump, new tank and new pickup. I have plenty of fuel to support my build, I am actually going with a Prosystems 830 carb this week and I have plenty of fuel to supply that. Most of your common issues with a mechanical system not supplying enough fuel (within reason) is not the line size its the fittings used, I used all AN fittings which will flow much better than traditional brass barb type fittings, they are very restrictive. So what your stating is that my fuel system isnt complete or competent because I am not running an electric pump?
There are plenty of 500-600 HP cars running 3/8 line and a mechanical pump. I value your opinion and take every ones point of view into consideration but it seems right now your reaching for the stars as there really is no supporting arguement that he needs to upgrade his entire fuel system for a 450-475 HP engine.
So, the basis to my recommendation is that if you're spending $10K on an engine...why leave .6 seconds on the table because you don't want to run an electric pump. **RobbMC pumps can handle the demands of high horsepower engine but require more clearancing than 5 1/2 min. with a dremel**
August 19th, 2012, 01:57 PM
#14
Registered User
Join Date: Jul 2011
Posts: 488
[QUOTE=ah64pilot;442411]" And with an electric I don't have to crank the engine over to get fuel pumping up to the carburetor. "
I am honestly trying to understand the benifits of running an elec over a mechanical fuel pump, Seriously I'm not trying to argue, I just don't understand the above statement. My car starts up leaning through the window tapping the switch. It cranks as fast if not faster than my new truck. Why would you want the fuel pumping if your not trying to crank it?
I am honestly trying to understand the benifits of running an elec over a mechanical fuel pump, Seriously I'm not trying to argue, I just don't understand the above statement. My car starts up leaning through the window tapping the switch. It cranks as fast if not faster than my new truck. Why would you want the fuel pumping if your not trying to crank it?
August 19th, 2012, 02:19 PM
#15
Registered User
Join Date: Apr 2011
Posts: 2,703
" And with an electric I don't have to crank the engine over to get fuel pumping up to the carburetor. "
I am honestly trying to understand the benifits of running an elec over a mechanical fuel pump, Seriously I'm not trying to argue, I just don't understand the above statement. My car starts up leaning through the window tapping the switch. It cranks as fast if not faster than my new truck. Why would you want the fuel pumping if your not trying to crank it?
I am honestly trying to understand the benifits of running an elec over a mechanical fuel pump, Seriously I'm not trying to argue, I just don't understand the above statement. My car starts up leaning through the window tapping the switch. It cranks as fast if not faster than my new truck. Why would you want the fuel pumping if your not trying to crank it?
A side benefit of having an electric pump is that there is fuel to the bowls before you crank rather than turning the engine over several times to get fuel up to the carburetor. It makes starting easier and is not unsafe as some have suggested. It's the same principle that all the new cars with fuel injection use...pressurize the fuel rail so that when the engine cranks the fuel is already there.
I'm not against using mechanical pumps. What I'm saying is if you are building a high horsepower engine with Edelbrock heads I would use an electric over the mechanical. The RobbMC pumps require quite a bit of clearance off of the Edelbrock head in order to work...and for the risk of hitting a water jacket as some have done, it's not worth it to me. In addition, the electric pumps have some benefit over the mechanical pumps as I have mentioned above.
In any case argue away...Steve, as I mentioned in my email, it's up to you. If you happen to go with the stroker combination just ask Bill what he suggests, I'm sure he'll set you straight.
August 19th, 2012, 02:46 PM
#16
Registered User
Join Date: Aug 2007
Posts: 2,250
Even after sitting for a few days or a week? Really? Awesome! Mine never did.
A side benefit of having an electric pump is that there is fuel to the bowls before you crank rather than turning the engine over several times to get fuel up to the carburetor. It makes starting easier and is not unsafe as some have suggested. It's the same principle that all the new cars with fuel injection use...pressurize the fuel rail so that when the engine cranks the fuel is already there.
A side benefit of having an electric pump is that there is fuel to the bowls before you crank rather than turning the engine over several times to get fuel up to the carburetor. It makes starting easier and is not unsafe as some have suggested. It's the same principle that all the new cars with fuel injection use...pressurize the fuel rail so that when the engine cranks the fuel is already there.
Having an EXTERNAL pump bolted to the under carriage is most certainly less safe than an in tank electric or block mounted mechanical. I agree that on a healthy BBO fuel delivery can be an issue, but on a street driven application a machanical is safer and more reliable, IMHO.
August 19th, 2012, 02:49 PM
#17
Registered User
Join Date: Jul 2011
Posts: 488
re
I see your point on the launch! That is good info for a drag racer that is pulling 2 or more g's off the line. But my car will never see the drag strip nor will it ever see 2+ g's. I have no clue what Steve's intention is.
With that being said you are still telling me that my car will wake up if I run an elec pump and I still dont see why, other that the loss of pressure launching on a drag strip on slicks (in which mine will never see any of the above) there is no reasoning why I should run an elec. Gaining over half a second is awesome, I would be thrilled, it was a major asset in your particular situation, but will the guy thats driving around town, cruising on the pro tour, and doing the every once in a while tire fry really going to see a difference? Probably not especially for the cost, time and effort involved.
So I think maybe he should look into a holley pump, grind less and problem solved unless he is going to be pulling 2+ g's off the line drag racing.
With that being said you are still telling me that my car will wake up if I run an elec pump and I still dont see why, other that the loss of pressure launching on a drag strip on slicks (in which mine will never see any of the above) there is no reasoning why I should run an elec. Gaining over half a second is awesome, I would be thrilled, it was a major asset in your particular situation, but will the guy thats driving around town, cruising on the pro tour, and doing the every once in a while tire fry really going to see a difference? Probably not especially for the cost, time and effort involved.
So I think maybe he should look into a holley pump, grind less and problem solved unless he is going to be pulling 2+ g's off the line drag racing.
Last edited by real57vetteguy; August 19th, 2012 at 02:52 PM.
August 19th, 2012, 03:56 PM
#18
Registered User
Thread Starter
Join Date: Aug 2010
Location: Southington,Connecticut
Posts: 970
This will be a street car and won't see any strip time. I just wanna Cruz my 68 442 convertible and be able to hang or smoke most of the 396's 440's,351's and some of the new stuff. I have a holly fuel pump and will give it a shot before going to an electric pump.
My car is a numbers matching car except the engine (but I have the original) and anything original that I took off the car I still have it. I see all the benefits of the electric pump but won't go there unless I have to at least not now because i am building this motor starting with a bare block and let's face it these things ain't cheap!
Thanks for the input guys I do appreciate it! I never tackle a project without posting here first TRUST ME there will be more post's!
My car is a numbers matching car except the engine (but I have the original) and anything original that I took off the car I still have it. I see all the benefits of the electric pump but won't go there unless I have to at least not now because i am building this motor starting with a bare block and let's face it these things ain't cheap!
Thanks for the input guys I do appreciate it! I never tackle a project without posting here first TRUST ME there will be more post's!
August 19th, 2012, 04:13 PM
#19
Registered User
Join Date: Jul 2011
Posts: 488
re
Ah64pilot,
It seems you had the exact problem I am currently having.
When you hit the drag stip for the first time you were let down by your time, and stated that you were running a stock fuel pump and that was the culprit. Shortly after you discovered that a clip had broken on your throttle cable thus preventing the secondaries from opening. (I am having the same issue with my lokar cable, it isnt giving me WOT so my secondaries arent opening) You fixed the cable issue, then you installed an elec pump. Back to the track and you were .6 faster.
Maybe a difference of opinion but the way you described losing power in your build thread is identical to how mine is running. I am getting plenty of fuel, just throttle cable is causing me problems with the secondaries, the car launches hard then falls on its face.
I would be willing to bet the majority of that .6 you gained was from installing the proper cable not the fuel pump change.
If you were so under fueled and the cable wasnt letting the secondaries open there was no possible way you were pulling enough G's to starve the pump.
It seems you had the exact problem I am currently having.
When you hit the drag stip for the first time you were let down by your time, and stated that you were running a stock fuel pump and that was the culprit. Shortly after you discovered that a clip had broken on your throttle cable thus preventing the secondaries from opening. (I am having the same issue with my lokar cable, it isnt giving me WOT so my secondaries arent opening) You fixed the cable issue, then you installed an elec pump. Back to the track and you were .6 faster.
Maybe a difference of opinion but the way you described losing power in your build thread is identical to how mine is running. I am getting plenty of fuel, just throttle cable is causing me problems with the secondaries, the car launches hard then falls on its face.
I would be willing to bet the majority of that .6 you gained was from installing the proper cable not the fuel pump change.
If you were so under fueled and the cable wasnt letting the secondaries open there was no possible way you were pulling enough G's to starve the pump.
Last edited by real57vetteguy; August 19th, 2012 at 04:20 PM.
August 19th, 2012, 04:23 PM
#20
Registered User
Join Date: Jul 2011
Posts: 488
This will be a street car and won't see any strip time. I just wanna Cruz my 68 442 convertible and be able to hang or smoke most of the 396's 440's,351's and some of the new stuff. I have a holly fuel pump and will give it a shot before going to an electric pump.
My car is a numbers matching car except the engine (but I have the original) and anything original that I took off the car I still have it. I see all the benefits of the electric pump but won't go there unless I have to at least not now because i am building this motor starting with a bare block and let's face it these things ain't cheap!
Thanks for the input guys I do appreciate it! I never tackle a project without posting here first TRUST ME there will be more post's!
My car is a numbers matching car except the engine (but I have the original) and anything original that I took off the car I still have it. I see all the benefits of the electric pump but won't go there unless I have to at least not now because i am building this motor starting with a bare block and let's face it these things ain't cheap!
Thanks for the input guys I do appreciate it! I never tackle a project without posting here first TRUST ME there will be more post's!
August 19th, 2012, 04:33 PM
#21
Registered User
Thread Starter
Join Date: Aug 2010
Location: Southington,Connecticut
Posts: 970
Will do!
Thanks again for the advice!
Thanks again for the advice!
August 19th, 2012, 04:51 PM
#22
Registered User
Join Date: Nov 2008
Location: Central Fl
Posts: 7,822
Hard lines or rubber lines, it doesn't matter if they're routed the same.
Use a good electric pump, Mallory, Walbro, Bosch and you'll be fine.
Use a good electric pump, Mallory, Walbro, Bosch and you'll be fine.
August 19th, 2012, 07:16 PM
#23
Registered User
Join Date: Jul 2011
Posts: 488
Re
A dyno run will tell you if you are leaning out. Run a good mech pump, and like we talked about with the lines and fittings. If it is starving for fuel because of the pump I will pay for half of your elec pump THATS A PROMISE!
"You are right, there are plenty of 500-600 hp cars running 3/8 line and a mechanical pump. I had one, until I switched it over...they will run on one, that's not the question. I picked up .6 in the 1/4 mile by going to electric. What was the problem? Fuel delivery on launch. Why? Because the G-force of the launch took 1/2 of the mechanical pumps pressure / volume away"
You again forgot to mention your cable wasnt letting the secondaries open......ok G-FORCE, how in the heck did you have any G-force if the secondaries werent openng, obviously the throttle wasnt opening all the way. Your car is awesome, your build is amazing, awesome work!!!! but this theory is an epic fail, you cannot blame a mechanical fuel pump on your times based upon a run where your carb wouldnt even open all the way, then fix the cable, and install an elec fuel pump and claim the entire problem was the fuel pump. There are hundreds of thousands of cars much faster running a 3/8 line and a mechanical pump that dont see "G force failure" .
G force failure is a real problem, in high horsepower cars pulling several G's. You fixed your issue when you fixed your cable, did you even give a high volume mech pump a try? nope!
"You are right, there are plenty of 500-600 hp cars running 3/8 line and a mechanical pump. I had one, until I switched it over...they will run on one, that's not the question. I picked up .6 in the 1/4 mile by going to electric. What was the problem? Fuel delivery on launch. Why? Because the G-force of the launch took 1/2 of the mechanical pumps pressure / volume away"
You again forgot to mention your cable wasnt letting the secondaries open......ok G-FORCE, how in the heck did you have any G-force if the secondaries werent openng, obviously the throttle wasnt opening all the way. Your car is awesome, your build is amazing, awesome work!!!! but this theory is an epic fail, you cannot blame a mechanical fuel pump on your times based upon a run where your carb wouldnt even open all the way, then fix the cable, and install an elec fuel pump and claim the entire problem was the fuel pump. There are hundreds of thousands of cars much faster running a 3/8 line and a mechanical pump that dont see "G force failure" .
G force failure is a real problem, in high horsepower cars pulling several G's. You fixed your issue when you fixed your cable, did you even give a high volume mech pump a try? nope!
Last edited by real57vetteguy; August 19th, 2012 at 08:36 PM.
August 19th, 2012, 09:12 PM
#24
Registered User
Join Date: Apr 2011
Posts: 2,703
Ah64pilot,
It seems you had the exact problem I am currently having.
When you hit the drag stip for the first time you were let down by your time, and stated that you were running a stock fuel pump and that was the culprit. Shortly after you discovered that a clip had broken on your throttle cable thus preventing the secondaries from opening. (I am having the same issue with my lokar cable, it isnt giving me WOT so my secondaries arent opening) You fixed the cable issue, then you installed an elec pump. Back to the track and you were .6 faster.
Maybe a difference of opinion but the way you described losing power in your build thread is identical to how mine is running. I am getting plenty of fuel, just throttle cable is causing me problems with the secondaries, the car launches hard then falls on its face.
I would be willing to bet the majority of that .6 you gained was from installing the proper cable not the fuel pump change.
If you were so under fueled and the cable wasnt letting the secondaries open there was no possible way you were pulling enough G's to starve the pump.
It seems you had the exact problem I am currently having.
When you hit the drag stip for the first time you were let down by your time, and stated that you were running a stock fuel pump and that was the culprit. Shortly after you discovered that a clip had broken on your throttle cable thus preventing the secondaries from opening. (I am having the same issue with my lokar cable, it isnt giving me WOT so my secondaries arent opening) You fixed the cable issue, then you installed an elec pump. Back to the track and you were .6 faster.
Maybe a difference of opinion but the way you described losing power in your build thread is identical to how mine is running. I am getting plenty of fuel, just throttle cable is causing me problems with the secondaries, the car launches hard then falls on its face.
I would be willing to bet the majority of that .6 you gained was from installing the proper cable not the fuel pump change.
If you were so under fueled and the cable wasnt letting the secondaries open there was no possible way you were pulling enough G's to starve the pump.
I'll tell you this, my car would hit hard and fall flat on it's face toward the end of 60' and never caught up. Before you go offering to pay for half a fuel pump, dyno a performance engine with a holley pump or put one on a track, I don't think you'd be so bold as to make that statement.
Self admittedly this is your first big block, and first carbureted engine...so how are you experienced enough to say what is sufficient for the engine Steve wants to build? He may not take it to the track, but if he builds a 496 CI stroker he's still gonna starve it for fuel at higher rpm...he'll find out when he races a newer Camaro SS or 5.0 Mustang. I tell you what, I'll post two videos...you see if you can tell a difference in the way the car ran. One is with a stock pump, the other with an electric.
August 19th, 2012, 09:18 PM
#25
Registered User
Join Date: Jul 2011
Posts: 488
The throttle cable breaking caused a stuck (high) idle condition that was misleading. While replacing it with the lokar cable I believe it wasn't opening all the way, but there's no way to really tell. I made a 12.7 pass before the suspected breakage and a 12.7 pass after the hung idle (suspected breakage) so who knows.
I'll tell you this, my car would hit hard and fall flat on it's face toward the end of 60' and never caught up. Before you go offering to pay for half a fuel pump, dyno a performance engine with a holley pump or put one on a track, I don't think you'd be so bold as to make that statement.
Self admittedly this is your first big block, and first carbureted engine...so how are you experienced enough to say what is sufficient for the engine Steve wants to build? He may not take it to the track, but if he builds a 496 CI stroker he's still gonna starve it for fuel at higher rpm...he'll find out when he races a newer Camaro SS or 5.0 Mustang. I tell you what, I'll post two videos...you see if you can tell a difference in the way the car ran. One is with a stock pump, the other with an electric.
http://youtu.be/uoyE-Ona8Gc
http://youtu.be/czV0ry_XSX4
I'll tell you this, my car would hit hard and fall flat on it's face toward the end of 60' and never caught up. Before you go offering to pay for half a fuel pump, dyno a performance engine with a holley pump or put one on a track, I don't think you'd be so bold as to make that statement.
Self admittedly this is your first big block, and first carbureted engine...so how are you experienced enough to say what is sufficient for the engine Steve wants to build? He may not take it to the track, but if he builds a 496 CI stroker he's still gonna starve it for fuel at higher rpm...he'll find out when he races a newer Camaro SS or 5.0 Mustang. I tell you what, I'll post two videos...you see if you can tell a difference in the way the car ran. One is with a stock pump, the other with an electric.
http://youtu.be/uoyE-Ona8Gc
http://youtu.be/czV0ry_XSX4
you are admitting you dont know if the throttle ever opened completly. just as mine is doing, and same thing launches hard and falls on its face, we both had throttle cable issues. Seems we have solved the problem, and as steve stated he wants a street driver so why would he build a 496?
"I'll tell you this, my car would hit hard and fall flat on it's face toward the end of 60' and never caught up."
it never caught up cause it was never at WOT
Last edited by real57vetteguy; August 19th, 2012 at 09:23 PM.
August 19th, 2012, 09:28 PM
#26
Registered User
Join Date: Jul 2011
Posts: 488
with my car right now, I can launch it and it will blow the tires off, and about 50-70 ft fall on its face, same thing secondaries arent opening due to the throttle cable
we are on the same page except you keep blaming a mechaincal fuel pump that you never gave a chance. and this all according to your build thread, you said it was because of G force that there was no way you were pulling. back up and look at the whole situation
we are on the same page except you keep blaming a mechaincal fuel pump that you never gave a chance. and this all according to your build thread, you said it was because of G force that there was no way you were pulling. back up and look at the whole situation
Last edited by real57vetteguy; August 19th, 2012 at 09:32 PM.
August 19th, 2012, 09:41 PM
#27
Registered User
Join Date: Apr 2011
Posts: 2,703
you are admitting you dont know if the throttle ever opened completly. just as mine is doing, and same thing launches hard and falls on its face, we both had throttle cable issues. Seems we have solved the problem, and as steve stated he wants a street driver so why would he build a 496?
"I'll tell you this, my car would hit hard and fall flat on it's face toward the end of 60' and never caught up."
it never caught up cause it was never at WOT
"I'll tell you this, my car would hit hard and fall flat on it's face toward the end of 60' and never caught up."
it never caught up cause it was never at WOT
with my car right now, I can launch it and it will blow the tires off, and about 50-70 ft fall on its face, same thing secondaries arent opening due to the throttle cable
we are on the same page except you keep blaming a mechaincal fuel pump that you never gave a chance. and this all according to your build thread, you said it was because of G force that there was no way you were pulling. back up and look at the whole situation
we are on the same page except you keep blaming a mechaincal fuel pump that you never gave a chance. and this all according to your build thread, you said it was because of G force that there was no way you were pulling. back up and look at the whole situation
August 19th, 2012, 09:41 PM
#28
Registered User
Join Date: Jul 2011
Posts: 488
re
The throttle cable breaking caused a stuck (high) idle condition that was misleading. While replacing it with the lokar cable I believe it wasn't opening all the way, but there's no way to really tell. I made a 12.7 pass before the suspected breakage and a 12.7 pass after the hung idle (suspected breakage) so who knows.
I'll tell you this, my car would hit hard and fall flat on it's face toward the end of 60' and never caught up. Before you go offering to pay for half a fuel pump, dyno a performance engine with a holley pump or put one on a track, I don't think you'd be so bold as to make that statement.
Self admittedly this is your first big block, and first carbureted engine...so how are you experienced enough to say what is sufficient for the engine Steve wants to build? He may not take it to the track, but if he builds a 496 CI stroker he's still gonna starve it for fuel at higher rpm...he'll find out when he races a newer Camaro SS or 5.0 Mustang. I tell you what, I'll post two videos...you see if you can tell a difference in the way the car ran. One is with a stock pump, the other with an electric.
http://youtu.be/uoyE-Ona8Gc
http://youtu.be/czV0ry_XSX4
I'll tell you this, my car would hit hard and fall flat on it's face toward the end of 60' and never caught up. Before you go offering to pay for half a fuel pump, dyno a performance engine with a holley pump or put one on a track, I don't think you'd be so bold as to make that statement.
Self admittedly this is your first big block, and first carbureted engine...so how are you experienced enough to say what is sufficient for the engine Steve wants to build? He may not take it to the track, but if he builds a 496 CI stroker he's still gonna starve it for fuel at higher rpm...he'll find out when he races a newer Camaro SS or 5.0 Mustang. I tell you what, I'll post two videos...you see if you can tell a difference in the way the car ran. One is with a stock pump, the other with an electric.
http://youtu.be/uoyE-Ona8Gc
http://youtu.be/czV0ry_XSX4
GAIN HALF A SECOND ET JUST BY USING AN ELECTRIC PUMP
if it were true i wouldbuild pumps
GET REAL DUDE
again epic fail!!!!
August 19th, 2012, 09:43 PM
#29
Registered User
Join Date: Apr 2011
Posts: 2,703
From PM so everyone get's the info...
"When you launch a car the fuel that is being "sucked" by a stock pump isn't being "sucked" at high enough of a velocity to overcome the motion of the car moving forward. It doesn't take much, in fact you'd be surprised at how little it actually does take. A stock pump puts out 7 psi. Using the fuel pressure loss calculator at http://www.wallaceracing.com/fuel-li...ssure-loss.php it is easy to see that a 1.85 60' time with 10' of fuel line will yield a 3.21 psi loss at the pump. So a stock pump putting out 7 psi under normal conditions loses 3.21 psi at launch...leaving the engine to run off of 3.79 psi AT WOT!
Now consider an electric pump "pushing" 14 psi up to the front of the car. The same car goes 1.85 60' and has 10' of fuel line. It loses the same 3.21 psi. But, the regulator has 10.79 psi of fuel and brings it down to 7 psi for the last 18" to the carb. See the difference?
While shredding your tires on the street is cool, it doesn't give you a real idea of how the car is running. Tell you what, take your car and put it up against a new SS Camaro at a 60 mph punch...you'll see what I'm talking about. I did that very experiment and got pulled on. After the pump, I put 5 cars on him to 100 mph.
So when you make your recommendations to guys that are just learning are you basing them off of facts like the above or just your limited experience? I understand that everyone has their own way of doing things but I don't think discounting others experience is appropriate given your limited exposure to high performance carbureted big block Oldsmobiles.
With regard to the throttle cable, I suspected my throttle cable wasn't opening all the way, but there really wasn't any way to tell. When I put the car together it did, but after it broke it didn't seem to. Maybe it was the throttle cable, but when guys like Dan Smith (DaVinci Performanc Carburetors) and David Nickens call me a dumbass for running a stock pump on a 500 hp big block I tend to listen.
Anyway, I posted some videos in that thread...check them out and tell me if you can tell a difference in the way the car acted with each pump...I couldn't until I got to the ticket booth.
Steve"
Quote:
Originally Posted by real57vetteguy
Hey,
I hope all is well, I am not trying to start a stink, I absolutly LOVE your build, AWESOME work. I just hate to see someone spend money, time and effort on things they dont need.
We all started out some where and it seems he has come here to learn.
Like I stated in the thread, I bet your times were improved more by the cable. As I am having the same problem with my cable.
Your right about the G force theory but honestly if you were under fueled by the pump and the cable issues you couldnt have been pulling enough g force to harm the fuel system unless your pump was just junk. Dont you agree?
I am not trying to belittle you at all, as I said I love your build and car but I think there was more to your power loss than just the pump.
Thanks
Mark
"When you launch a car the fuel that is being "sucked" by a stock pump isn't being "sucked" at high enough of a velocity to overcome the motion of the car moving forward. It doesn't take much, in fact you'd be surprised at how little it actually does take. A stock pump puts out 7 psi. Using the fuel pressure loss calculator at http://www.wallaceracing.com/fuel-li...ssure-loss.php it is easy to see that a 1.85 60' time with 10' of fuel line will yield a 3.21 psi loss at the pump. So a stock pump putting out 7 psi under normal conditions loses 3.21 psi at launch...leaving the engine to run off of 3.79 psi AT WOT!
Now consider an electric pump "pushing" 14 psi up to the front of the car. The same car goes 1.85 60' and has 10' of fuel line. It loses the same 3.21 psi. But, the regulator has 10.79 psi of fuel and brings it down to 7 psi for the last 18" to the carb. See the difference?
While shredding your tires on the street is cool, it doesn't give you a real idea of how the car is running. Tell you what, take your car and put it up against a new SS Camaro at a 60 mph punch...you'll see what I'm talking about. I did that very experiment and got pulled on. After the pump, I put 5 cars on him to 100 mph.
So when you make your recommendations to guys that are just learning are you basing them off of facts like the above or just your limited experience? I understand that everyone has their own way of doing things but I don't think discounting others experience is appropriate given your limited exposure to high performance carbureted big block Oldsmobiles.
With regard to the throttle cable, I suspected my throttle cable wasn't opening all the way, but there really wasn't any way to tell. When I put the car together it did, but after it broke it didn't seem to. Maybe it was the throttle cable, but when guys like Dan Smith (DaVinci Performanc Carburetors) and David Nickens call me a dumbass for running a stock pump on a 500 hp big block I tend to listen.
Anyway, I posted some videos in that thread...check them out and tell me if you can tell a difference in the way the car acted with each pump...I couldn't until I got to the ticket booth.
Steve"
Quote:
Originally Posted by real57vetteguy
Hey,
I hope all is well, I am not trying to start a stink, I absolutly LOVE your build, AWESOME work. I just hate to see someone spend money, time and effort on things they dont need.
We all started out some where and it seems he has come here to learn.
Like I stated in the thread, I bet your times were improved more by the cable. As I am having the same problem with my cable.
Your right about the G force theory but honestly if you were under fueled by the pump and the cable issues you couldnt have been pulling enough g force to harm the fuel system unless your pump was just junk. Dont you agree?
I am not trying to belittle you at all, as I said I love your build and car but I think there was more to your power loss than just the pump.
Thanks
Mark
August 19th, 2012, 09:46 PM
#30
Registered User
Join Date: Apr 2011
Posts: 2,703
Well lets go away from street cars and talk about drag cars only, if your theory were correct, that people can gain lets say up to .6 on the track then why isnt all the eletric fuel pump companies jumping all over that? If it were half true the companies would make a marketing scheme to pump that up like no other.
GAIN HALF A SECOND ET JUST BY USING AN ELECTRIC PUMP
if it were true i wouldbuild pumps
GET REAL DUDE
again epic fail!!!!
GAIN HALF A SECOND ET JUST BY USING AN ELECTRIC PUMP
if it were true i wouldbuild pumps
GET REAL DUDE
again epic fail!!!!
I am.
Last edited by ah64pilot; August 19th, 2012 at 09:50 PM.
August 19th, 2012, 09:53 PM
#31
Registered User
Join Date: Apr 2011
Posts: 2,703
Serenity now:
This message is hidden because real57vetteguy is on your ignore list.
Ahh, that's better.
This message is hidden because real57vetteguy is on your ignore list.
Ahh, that's better.
August 19th, 2012, 09:55 PM
#32
Registered User
Join Date: Jul 2011
Posts: 488
re
What i Said was over half a second in 1/4 miles times by switching fuel pumps from a good mechanical to an electric on a 500 hp car is not real, maybe in muppet land, maybe in marvel comics, but not in the real world again your issue was the throttle cable problem. Unless the mech fuel pump you had was worn out totally. Its common sense that you didnt gain that much by a fuel pump change
August 19th, 2012, 10:10 PM
#33
Registered User
Join Date: Jul 2011
Posts: 488
Well I would say for all of those looking into this thread I was blocked by AH64PILOT, after during PM's he couldnt explain why he said his throttle cable broke and he couldnt get full throttle but blamed his power loss on a mechanical fuel pump and not a faulty cable. HMMM then he fixed the cable and put an elec fuel pump in and ran better times, i would think that a fully open carb would give one better times but he seems to think WOT doesnt matter a elec fuel pump makes a better time???? go figure???
August 19th, 2012, 10:21 PM
#34
Registered User
Join Date: Apr 2011
Posts: 2,703
I can't see what this guy is saying but for those of you that know me know I'm here to help, not start crap. If experience speaks for anything I'm fairly certain you will know who's speaking from it, and who's, well, blowing smoke.
August 20th, 2012, 09:43 AM
#35
Registered User
Join Date: Feb 2008
Location: Plano, TX
Posts: 11,798
Guys, let's not start an argument here - just share what has worked or doesn't work. Theory leaves too many open variables and may or may not work for everyone.
August 20th, 2012, 11:24 AM
#36
Registered User
Join Date: May 2008
Location: Austin, Texas
Posts: 3,127
.....and now back to our regularly scheduled programming here on RealOldsPower.com.
OOOps...I meant ClassicOlds.com....I could have sworn this was ROP.com. - apparently not but the similarities are striking.
OOOps...I meant ClassicOlds.com....I could have sworn this was ROP.com. - apparently not but the similarities are striking.
August 20th, 2012, 01:44 PM
#38
car guy
Join Date: Apr 2008
Location: Dallas TX
Posts: 5,656
My experience a street car it won't matter. A drag car with stickies with a decent 60 ft will benifit somewhere in the 400HP range and up. That being said I picked up a set of Edelbrock heads a couple years ago that only had about .250 cut to clear a pump and had a pinhole to water.
August 20th, 2012, 04:56 PM
#39
Registered User
Join Date: Nov 2007
Location: Rathdrum, Idano
Posts: 9,127
You can't file much. About a 1/4" V notch and that's it or your headed for trouble. I did this on the 455 in my 57 and the fuel pump clears by a hair.
August 20th, 2012, 06:53 PM
#40
Registered User
Join Date: Jul 2011
Posts: 488
Its all good. I feel as if I tried to compliment AH64PILOTS build, etc etc. But its evident in his thread according to his posts that his throttle cable had issues and the secondaries werent opening. He repaired that and changed his pump to electric. The result was a .6 gain in the 1/4 mile. I think that is awesome but there cannot be a legitmate claim that the electric pump resulted in a .6 increase in 1/4 mile time when the owner himself admits that he didnt know if his throttle was opening all the way before he changed the cable (in which his build thread states that the secondaries were not even opening)
If you take the build thread into consideration the posts that stuck out in my head is that he just grabbed a mechanical pump at a local parts store and that his cable had issues and the secondaies were not opening, then he was let down by his 1/4 mile times. I can see why but how with the above taken into consideration was he pulling enough G's off the line to starve the engine of fuel?
With all the above being said it seems to be very unfair to claim the electric pump resuled in such a drastic increase.
Forums are a dangerious thing sometimes. The starter of this thread asked a question about fuel pump clearence, and was advised that his car will perform poorly if he doesnt install an electric pump. He was advised that gains of .6 in a 1/4 mile would be seen from switching to an electric which in most cases is simply untrue.
If someone is here to learn and ask questions and their hard earned money, labor and time is going to be directly affected by the responses he receives, well, he should receive accurate information. Upon asking AH64PIlOT about why he never mentioned his throttle cable issue he responded with some childesh name calling, copying and pasting things from magazines (which now much do we beleive from paid sponser magazines) and telling me to STFU etc? C'mon its a forum, lets be civil with our debates, I however did state that his theory for this street driver build was an epic failure and I should have been more polite, I do apologize for that.
I do however stand behind my mentality and that is, for a 450 hp street driven Big block Olds, 3/8 line, proper fittings and a good mechanical fuel pump will supply all the fuel you need.
I again apologize for all the back and forth posts, as I do really like AH64PILOT's car, build and hard work. I just feel there is more credit due to the throttle cable repair than he is giving.
If you take the build thread into consideration the posts that stuck out in my head is that he just grabbed a mechanical pump at a local parts store and that his cable had issues and the secondaies were not opening, then he was let down by his 1/4 mile times. I can see why but how with the above taken into consideration was he pulling enough G's off the line to starve the engine of fuel?
With all the above being said it seems to be very unfair to claim the electric pump resuled in such a drastic increase.
Forums are a dangerious thing sometimes. The starter of this thread asked a question about fuel pump clearence, and was advised that his car will perform poorly if he doesnt install an electric pump. He was advised that gains of .6 in a 1/4 mile would be seen from switching to an electric which in most cases is simply untrue.
If someone is here to learn and ask questions and their hard earned money, labor and time is going to be directly affected by the responses he receives, well, he should receive accurate information. Upon asking AH64PIlOT about why he never mentioned his throttle cable issue he responded with some childesh name calling, copying and pasting things from magazines (which now much do we beleive from paid sponser magazines) and telling me to STFU etc? C'mon its a forum, lets be civil with our debates, I however did state that his theory for this street driver build was an epic failure and I should have been more polite, I do apologize for that.
I do however stand behind my mentality and that is, for a 450 hp street driven Big block Olds, 3/8 line, proper fittings and a good mechanical fuel pump will supply all the fuel you need.
I again apologize for all the back and forth posts, as I do really like AH64PILOT's car, build and hard work. I just feel there is more credit due to the throttle cable repair than he is giving.
