Best combo of aftermarket parts for low end torque
December 29th, 2013, 04:48 AM
#1
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Best combo of aftermarket parts for low end torque
For my 72 cutlass S 350 5.7(daily driver)
Cam selection(im thinking crane cams), what specs would give me the "best of both worlds" of torque and drivability?
Rocker arm ratios (im thinking crane cams gold ),what determines the ideal ratio?
Heads, edelbrock rpm performer or afr?
Whats the purpose/benefit of porting heads and/or doing valve job?
Intake and carb, for the sake of guaranteed compatibility im thinking edelbrock performer intake and 650 thunder tvs carb
Lastly, cold air intakes, hype or god send?
Cam selection(im thinking crane cams), what specs would give me the "best of both worlds" of torque and drivability?
Rocker arm ratios (im thinking crane cams gold ),what determines the ideal ratio?
Heads, edelbrock rpm performer or afr?
Whats the purpose/benefit of porting heads and/or doing valve job?
Intake and carb, for the sake of guaranteed compatibility im thinking edelbrock performer intake and 650 thunder tvs carb
Lastly, cold air intakes, hype or god send?
December 29th, 2013, 04:59 AM
#2
Out of Line, Everytime😉
Join Date: Dec 2006
Location: Melville, Saskatchewan
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You need the the RPM intake for the RPM heads due to the taller ports. Cutlassefi can even get custom grinds and is an Erson and Lunati dealer and engine builder. Get the Street Demon 750 carb and tuning kit, a superior version of the old AVS. Get either Scorpion or Harland Sharp 1.7 to 1 rockers, gain lift and don't cost more then the 1.6 ratio. Bowl work and bigger valves almost always seems to gain everywhere. The Olds 350 has a nice big bore that can go almost .100 over, so fitting big valves isn't a problem. Cool air makes power, depends on design for the amount gained.
Last edited by olds 307 and 403; December 29th, 2013 at 05:04 AM.
December 29th, 2013, 05:08 AM
#3
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You need the the RPM intake for the RPM heads due to the taller ports. Cutlassefi can even get custom grinds and is an Erson and Lunati dealer and engine builder. Get the Street Demon 750 carb and tuning kit, a superior version of the old AVS. Get either Scorpion or Harland Sharp 1.7 to 1 rockers, gain lift and don't cost more then the 1.6 ratio.
December 29th, 2013, 05:15 AM
#4
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No, this is an all new carb based off the AVS and Thermoquad. All new castings with better materials and the problem areas fixed like the O rings eliminated and better choke. It fits both square and spread bore intakes.
December 29th, 2013, 05:59 AM
#5
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I looked it up (assuming that you were talking about the street demon 750 from demon carbs) and it seems pretty sweet and straight forward, fair price too. Good lookin' out
December 29th, 2013, 07:12 AM
#6
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Location: Central Fl
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For my 72 cutlass S 350 5.7(daily driver)
Cam selection(im thinking crane cams), what specs would give me the "best of both worlds" of torque and drivability?
Rocker arm ratios (im thinking crane cams gold ),what determines the ideal ratio?
Heads, edelbrock rpm performer or afr?
Whats the purpose/benefit of porting heads and/or doing valve job?
Intake and carb, for the sake of guaranteed compatibility im thinking edelbrock performer intake and 650 thunder tvs carb
Lastly, cold air intakes, hype or god send?
Cam selection(im thinking crane cams), what specs would give me the "best of both worlds" of torque and drivability?
Rocker arm ratios (im thinking crane cams gold ),what determines the ideal ratio?
Heads, edelbrock rpm performer or afr?
Whats the purpose/benefit of porting heads and/or doing valve job?
Intake and carb, for the sake of guaranteed compatibility im thinking edelbrock performer intake and 650 thunder tvs carb
Lastly, cold air intakes, hype or god send?
I see no mention of raising the compression. That should be first.
And just rebuilding the carb you have won't necessarily make it run less rich. It needs to be re-jetted and adjusted. If your mechanic doesn't know that or can't perform that task then find another mechanic.
December 29th, 2013, 08:40 AM
#7
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Moving to Edelbrock heads is a fair bit of work - I did it on my 403 - with several repercussions on other ares (fuel delivery being a big one).
Given your starting point it might be a good idea to keep it simple. Basic machining, basic port work on the heads, get the compression up around 9.5:1, a moderate cam and some headers. That will really wake it up.
There are a lot of variables so it's hard to get a full recipe based on what you've provided. You can do a lot of reading here, on 442.com and ROP and make your own conclusions, or hand it over to a builder to make the combo. Even then picking the right builder is very important.
CAI isn't necessarily worth it on a street car. I'd recommend running a stock cleaner housing and running a tube up to the headlights.
Given your starting point it might be a good idea to keep it simple. Basic machining, basic port work on the heads, get the compression up around 9.5:1, a moderate cam and some headers. That will really wake it up.
There are a lot of variables so it's hard to get a full recipe based on what you've provided. You can do a lot of reading here, on 442.com and ROP and make your own conclusions, or hand it over to a builder to make the combo. Even then picking the right builder is very important.
CAI isn't necessarily worth it on a street car. I'd recommend running a stock cleaner housing and running a tube up to the headlights.
December 29th, 2013, 01:32 PM
#8
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Join Date: Feb 2013
Posts: 178
I see no mention of raising the compression. That should be first.
And just rebuilding the carb you have won't necessarily make it run less rich. It needs to be re-jetted and adjusted. If your mechanic doesn't know that or can't perform that task then find another mechanic.
And just rebuilding the carb you have won't necessarily make it run less rich. It needs to be re-jetted and adjusted. If your mechanic doesn't know that or can't perform that task then find another mechanic.
Mechanics in HI that know american muscle is no small feat my friend, this is import tuner central :/ (HI is japans 2nd home)
December 29th, 2013, 01:52 PM
#9
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Join Date: Feb 2013
Posts: 178
Moving to Edelbrock heads is a fair bit of work - I did it on my 403 - with several repercussions on other ares (fuel delivery being a big one).
Given your starting point it might be a good idea to keep it simple. Basic machining, basic port work on the heads, get the compression up around 9.5:1, a moderate cam and some headers. That will really wake it up.
There are a lot of variables so it's hard to get a full recipe based on what you've provided. You can do a lot of reading here, on 442.com and ROP and make your own conclusions, or hand it over to a builder to make the combo. Even then picking the right builder is very important.
CAI isn't necessarily worth it on a street car. I'd recommend running a stock cleaner housing and running a tube up to the headlights.
Given your starting point it might be a good idea to keep it simple. Basic machining, basic port work on the heads, get the compression up around 9.5:1, a moderate cam and some headers. That will really wake it up.
There are a lot of variables so it's hard to get a full recipe based on what you've provided. You can do a lot of reading here, on 442.com and ROP and make your own conclusions, or hand it over to a builder to make the combo. Even then picking the right builder is very important.
CAI isn't necessarily worth it on a street car. I'd recommend running a stock cleaner housing and running a tube up to the headlights.
December 29th, 2013, 02:12 PM
#10
Connoisseur d'Junque
Join Date: Sep 2010
Location: The Hudson Valley
Posts: 21,183
As I said here:
"OldSkool84, you are asking much better questions now, but you are asking questions that can't or shouldn't be answered on an internet forum.
You now need to go out and get some books (or even on-line resources) about engine design and performance and read them in order to gain a basic understanding of piston design, piston materials, head flow and porting, compression ratios, flame front propagation, valve and ignition timing, and carburetion / fuel injection.
See the current thread on home porting, for instance.
Once you have absorbed a basic level of knowledge, you will be better able to fix your own engine, and to ask the sorts of questions that will allow you to properly plan the sorts of upgrades you would like."
You raise compression by using pistons with less dish, decking the block, and or making the combustion chambers smaller.
At this point, it is (slowly) becoming clear that you have an engine with a number of modifications, none of which was, with any certainty, done by someone competent, and none of which, as far as we can tell, was planned to work with any of the others.
We don't know, for certain, what your compression is. The heads have been off at least once. Maybe the pistons have been changed. Maybe they haven't. You have no idea, and we have even less of a chance of knowing.
You have no idea of the specifications of your cam either, and are highly unlikely to grab a dial indicator, a mount, and a degree wheel and find out, and we, again, know even less than you do.
We have no idea whether "dropping in a new carb" would help anything at all, though, in general, most of us here would oppose any suggestion that throwing new parts at a car until it works right is a good idea.
The best idea is to diagnose what your problem is, and then do what needs to be done to fix that problem. None of us here can do that through the magic of the interwebs, thought many of us could do it in person.
As has been suggested, your best course of action would be to find a competent mechanic somewhere near you to untangle the mess made by others, and point you in the right direction. That, and do a lot of reading.
Oh, and why do you believe that your engine is running too rich?
- Eric
"OldSkool84, you are asking much better questions now, but you are asking questions that can't or shouldn't be answered on an internet forum.
You now need to go out and get some books (or even on-line resources) about engine design and performance and read them in order to gain a basic understanding of piston design, piston materials, head flow and porting, compression ratios, flame front propagation, valve and ignition timing, and carburetion / fuel injection.
See the current thread on home porting, for instance.
Once you have absorbed a basic level of knowledge, you will be better able to fix your own engine, and to ask the sorts of questions that will allow you to properly plan the sorts of upgrades you would like."
You raise compression by using pistons with less dish, decking the block, and or making the combustion chambers smaller.
I had a blown head gasket not too long ago and while the heads were at the machine shop being tested, the guy convinced me to do a port job so thats done already. Car came with headers as welll. As for the cam , im not 100% committed to swapping it yet. Do you think dropping a new carb would help it run smoother?
We don't know, for certain, what your compression is. The heads have been off at least once. Maybe the pistons have been changed. Maybe they haven't. You have no idea, and we have even less of a chance of knowing.
You have no idea of the specifications of your cam either, and are highly unlikely to grab a dial indicator, a mount, and a degree wheel and find out, and we, again, know even less than you do.
We have no idea whether "dropping in a new carb" would help anything at all, though, in general, most of us here would oppose any suggestion that throwing new parts at a car until it works right is a good idea.
The best idea is to diagnose what your problem is, and then do what needs to be done to fix that problem. None of us here can do that through the magic of the interwebs, thought many of us could do it in person.
As has been suggested, your best course of action would be to find a competent mechanic somewhere near you to untangle the mess made by others, and point you in the right direction. That, and do a lot of reading.
Oh, and why do you believe that your engine is running too rich?
- Eric
December 29th, 2013, 02:41 PM
#12
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Join Date: Nov 2008
Location: Central Fl
Posts: 7,863
December 30th, 2013, 05:27 PM
#13
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Thread Starter
Join Date: Feb 2013
Posts: 178
As I said here:
"OldSkool84, you are asking much better questions now, but you are asking questions that can't or shouldn't be answered on an internet forum.
You now need to go out and get some books (or even on-line resources) about engine design and performance and read them in order to gain a basic understanding of piston design, piston materials, head flow and porting, compression ratios, flame front propagation, valve and ignition timing, and carburetion / fuel injection.
See the current thread on home porting, for instance.
Once you have absorbed a basic level of knowledge, you will be better able to fix your own engine, and to ask the sorts of questions that will allow you to properly plan the sorts of upgrades you would like."
You raise compression by using pistons with less dish, decking the block, and or making the combustion chambers smaller.
At this point, it is (slowly) becoming clear that you have an engine with a number of modifications, none of which was, with any certainty, done by someone competent, and none of which, as far as we can tell, was planned to work with any of the others.
We don't know, for certain, what your compression is. The heads have been off at least once. Maybe the pistons have been changed. Maybe they haven't. You have no idea, and we have even less of a chance of knowing.
You have no idea of the specifications of your cam either, and are highly unlikely to grab a dial indicator, a mount, and a degree wheel and find out, and we, again, know even less than you do.
We have no idea whether "dropping in a new carb" would help anything at all, though, in general, most of us here would oppose any suggestion that throwing new parts at a car until it works right is a good idea.
The best idea is to diagnose what your problem is, and then do what needs to be done to fix that problem. None of us here can do that through the magic of the interwebs, thought many of us could do it in person.
As has been suggested, your best course of action would be to find a competent mechanic somewhere near you to untangle the mess made by others, and point you in the right direction. That, and do a lot of reading.
Oh, and why do you believe that your engine is running too rich?
- Eric
"OldSkool84, you are asking much better questions now, but you are asking questions that can't or shouldn't be answered on an internet forum.
You now need to go out and get some books (or even on-line resources) about engine design and performance and read them in order to gain a basic understanding of piston design, piston materials, head flow and porting, compression ratios, flame front propagation, valve and ignition timing, and carburetion / fuel injection.
See the current thread on home porting, for instance.
Once you have absorbed a basic level of knowledge, you will be better able to fix your own engine, and to ask the sorts of questions that will allow you to properly plan the sorts of upgrades you would like."
You raise compression by using pistons with less dish, decking the block, and or making the combustion chambers smaller.
At this point, it is (slowly) becoming clear that you have an engine with a number of modifications, none of which was, with any certainty, done by someone competent, and none of which, as far as we can tell, was planned to work with any of the others.
We don't know, for certain, what your compression is. The heads have been off at least once. Maybe the pistons have been changed. Maybe they haven't. You have no idea, and we have even less of a chance of knowing.
You have no idea of the specifications of your cam either, and are highly unlikely to grab a dial indicator, a mount, and a degree wheel and find out, and we, again, know even less than you do.
We have no idea whether "dropping in a new carb" would help anything at all, though, in general, most of us here would oppose any suggestion that throwing new parts at a car until it works right is a good idea.
The best idea is to diagnose what your problem is, and then do what needs to be done to fix that problem. None of us here can do that through the magic of the interwebs, thought many of us could do it in person.
As has been suggested, your best course of action would be to find a competent mechanic somewhere near you to untangle the mess made by others, and point you in the right direction. That, and do a lot of reading.
Oh, and why do you believe that your engine is running too rich?
- Eric
December 30th, 2013, 05:50 PM
#15
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Join Date: Nov 2008
Location: Central Fl
Posts: 7,863
Either find another shop or buy a wideband O2. Then have the shop tune it for free because you're telling them how to work on your car.
December 31st, 2013, 12:37 PM
#17
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Yea it would make sense with all the issues im having. Im thinking of getting a compression test done as well
December 31st, 2013, 12:59 PM
#19
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January 1st, 2014, 09:04 AM
#21
Out of Line, Everytime😉
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Biggest problem is your engine is 8 to 1 compression, give or take with stock pistons. I have a stock 76 350 that runs great with similar compression. But it will never run better than high 14's in the 1/4, I don't care who tunes it. Plus I have better trans and rear gearing. The Street Demon 625 cfm would be plenty for your engine as is, that 750 Demon Holley clone is too big for your current set up. If your compression is low or uneven, it is overhaul time. Any of the avialable forged pistons would wake up that engine big time by bringing it up to 9.5-10.25 to 1, depending on the piston dish size.
January 1st, 2014, 09:28 AM
#22
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How do you know whats in his engine as he does not either. He has no clue as to what is wrong with it, how it was built, or any direction other than what he has read or was mindlessly suggested. So any speculation for a direction is moot until his baseline is established.
January 1st, 2014, 10:00 AM
#23
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Location: Iowa
Posts: 1,130
How do you know whats in his engine as he does not either. He has no clue as to what is wrong with it, how it was built, or any direction other than what he has read or was mindlessly suggested. So any speculation for a direction is moot until his baseline is established.
LOL.....yup.
January 1st, 2014, 11:52 AM
#24
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A friend hooked me up with a mechanic who deff gives me a warm and fuzzy feeling that he could help get my baby running smooth. Although he too recommended a new carb(edelbrock 600 cfm afb (1405) ) , i think the smartest thing i could do is run some diagnostics first I.e- compression test , wideband O2,etc. To help get a better idea of what kind of mods have been done. Thx for the input just the same tho Olds 307&403
January 1st, 2014, 02:03 PM
#25
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Location: Poteau, Ok
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Again, before you buy a new carb, first see if there is anything wrong with the one you have. The carb you have is a good carb, it may just be out of adjustment. Anyone that diagnoses an engine problem without troubleshooting is doing you an injustice.
Good luck!
Good luck!
January 1st, 2014, 03:03 PM
#26
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Absolutely, thx!
January 1st, 2014, 05:31 PM
#27
Out of Line, Everytime😉
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We are not "mindlessly" suggesting anything. That 750 cfm square bore carb will need leaned out a lot if the engine is stock. A compression test and maybe even a tear down is in order on the carb and engine.
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