Winter Restless
December 20th, 2018, 06:11 AM
#1
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Join Date: Mar 2015
Location: Farnhamville, Iowa
Posts: 332
Winter Restless
Though it has been a mild winter so far here in Iowa, I am getting restless and pondering projects or changes to my car. One of the top things that always pops to mind is how i built my olds 455. Intake issues, timing with high compression.
When I put the motor together I opted for higher compression pistons shooting for 10:1 or so. Builder advised me would have to run higher octane gas. At that time 89 octane gas was the norm in my state with 91 octane pumps sporadic. Between the time the engine was completed and the body work done and car beck on the road, the state changed fuel requirements so now we have 87 octane as the norm. Still have the sporadic 91 pumps.
Shop tuned my car, down to 29/30 TDC without the vac advance line hooked up, on 91 octane gas. At that point the engine would run and not ping. I bought an adjustable vac advance for the distributor, but he didn't think it would be worth trying to tune with. Plus with the olds distributor location of being up against the firewall and the vac advance at an angle of getting that alen wrench in to adjust... Pain in the ***. We tuned it up to 36 TDC like most big blocks I am told are set, and the car had power and launch, but with pinging right off.
I emailed mondello performance about the problem, which piston to select. Advised I have a 455 punched over 30, ga heads with no additional porting, but new valves, guides, etc.. Received a reply to use 28 cc pistons (mid comp) and to open up the lobes. I am going to dig out the receipt from the build and figure out what cc Keith Black Pistons I used years back for comparison.
My goal is to pull the motor:
have the intake machined to match how the decked block and heads now fit. We had to use a 3 piece intake kit to get it to seal. First machine shop must not of machined the intake to match the change in angle due to the decking.
Have a piston setup that does not require 91 + octane where. While engine is out, put the engine on a dyno and tune it with the new pistons on 87 octane, with the adjustable vac to gain the most power.
I have word two shops have a dyno in my area, just need to talk with them on what that would cost to do all the above. I assembled the motor the first time and ran into that intake issue with sealing and had another shop solve that issue, though we didn't machine the intake at that time. Easier to do that with the engine out.
When I put the motor together I opted for higher compression pistons shooting for 10:1 or so. Builder advised me would have to run higher octane gas. At that time 89 octane gas was the norm in my state with 91 octane pumps sporadic. Between the time the engine was completed and the body work done and car beck on the road, the state changed fuel requirements so now we have 87 octane as the norm. Still have the sporadic 91 pumps.
Shop tuned my car, down to 29/30 TDC without the vac advance line hooked up, on 91 octane gas. At that point the engine would run and not ping. I bought an adjustable vac advance for the distributor, but he didn't think it would be worth trying to tune with. Plus with the olds distributor location of being up against the firewall and the vac advance at an angle of getting that alen wrench in to adjust... Pain in the ***. We tuned it up to 36 TDC like most big blocks I am told are set, and the car had power and launch, but with pinging right off.
I emailed mondello performance about the problem, which piston to select. Advised I have a 455 punched over 30, ga heads with no additional porting, but new valves, guides, etc.. Received a reply to use 28 cc pistons (mid comp) and to open up the lobes. I am going to dig out the receipt from the build and figure out what cc Keith Black Pistons I used years back for comparison.
My goal is to pull the motor:
have the intake machined to match how the decked block and heads now fit. We had to use a 3 piece intake kit to get it to seal. First machine shop must not of machined the intake to match the change in angle due to the decking.
Have a piston setup that does not require 91 + octane where. While engine is out, put the engine on a dyno and tune it with the new pistons on 87 octane, with the adjustable vac to gain the most power.
I have word two shops have a dyno in my area, just need to talk with them on what that would cost to do all the above. I assembled the motor the first time and ran into that intake issue with sealing and had another shop solve that issue, though we didn't machine the intake at that time. Easier to do that with the engine out.
December 20th, 2018, 08:24 AM
#2
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Join Date: Nov 2008
Location: Central Fl
Posts: 7,824
A few things;
I didn't see anywhere that you tuned this with a wideband of any sort at any time, did you?
I've done a bunch of 10.0:1 builds that ran fine on 91, when tuned properly. And typically the correct timing was 33-34, not 29-30 or 36. (I sure wish guys would get off that automatic 36* number. Most everything I've done runs best around 33-34, not 36).
And remember the vacuum advance does nothing at WOT, only part throttle.
Buy a good wideband first before you start tearing into your build. I'll bet you'll find some issues there.
P.S. You may also want to think about maybe aluminum heads instead of a piston change. The Procomps are typically 83-84cc's which with the Wiseco piston, should give you 9.75::1 or so. With the right tune that should run on 89.
I didn't see anywhere that you tuned this with a wideband of any sort at any time, did you?
I've done a bunch of 10.0:1 builds that ran fine on 91, when tuned properly. And typically the correct timing was 33-34, not 29-30 or 36. (I sure wish guys would get off that automatic 36* number. Most everything I've done runs best around 33-34, not 36).
And remember the vacuum advance does nothing at WOT, only part throttle.
Buy a good wideband first before you start tearing into your build. I'll bet you'll find some issues there.
P.S. You may also want to think about maybe aluminum heads instead of a piston change. The Procomps are typically 83-84cc's which with the Wiseco piston, should give you 9.75::1 or so. With the right tune that should run on 89.
Last edited by cutlassefi; December 20th, 2018 at 08:32 AM.
December 21st, 2018, 05:07 PM
#3
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Join Date: Jan 2010
Location: central Indiana
Posts: 5,232
If the engine is mechanically sound ,and the only issue is pinging on pump gas, get some aftermarket aluminum heads. They are a bolt on 50hp, and will almost certainly cure your pinging issue.
Second, if the Mondello your emailing is in California, delete and disregard any advice Lynn has provided!! Lynn has run joe Mondello hard earned reputation into the ground. Mondello today is far different than when joe ran the place. Bernard Mondello is Joe’s son, and is a stand up guy just like his dad. Mark (Cutlass efi) Rocket racing, BTR in New York, all all well know Olds specialist who can help steer you in the right direction
Second, if the Mondello your emailing is in California, delete and disregard any advice Lynn has provided!! Lynn has run joe Mondello hard earned reputation into the ground. Mondello today is far different than when joe ran the place. Bernard Mondello is Joe’s son, and is a stand up guy just like his dad. Mark (Cutlass efi) Rocket racing, BTR in New York, all all well know Olds specialist who can help steer you in the right direction
Last edited by matt69olds; December 22nd, 2018 at 06:19 PM.
December 22nd, 2018, 07:21 AM
#4
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Join Date: Mar 2015
Location: Farnhamville, Iowa
Posts: 332
Thank you Matt, heard that about Lynn from a few.
Will check out the procomp heads and top end. Would rather retain what I have as I am guessing couple grand for a top end.
Mark, will look around for a shop with a wideband timer, and who regularly works on these older engines. Hard to find in my rural area. The small shops are either shops that just do the basic repairs on newer vehicles, and if they had experience in older engines, it was a long time ago...
Other shops are those that may build engines for the local dirt track hobbyists... Those are mainly SB chevies...
Be nice to find someone with a car dino to tune and test and be right when one drives it out the door. Will post the specs of the piston after work.
Alex
Will check out the procomp heads and top end. Would rather retain what I have as I am guessing couple grand for a top end.
Mark, will look around for a shop with a wideband timer, and who regularly works on these older engines. Hard to find in my rural area. The small shops are either shops that just do the basic repairs on newer vehicles, and if they had experience in older engines, it was a long time ago...
Other shops are those that may build engines for the local dirt track hobbyists... Those are mainly SB chevies...
Be nice to find someone with a car dino to tune and test and be right when one drives it out the door. Will post the specs of the piston after work.
Alex
December 22nd, 2018, 08:42 AM
#5
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Join Date: Sep 2017
Location: St. Paul Minnesota
Posts: 4,004
I think you are going to a lot of expense for no gain. 36 is just a "number", just like age and weight. Cutlassefi is correct. Ping is a sign of fuel/air mixture being ignited and burning (expanding) before TDC and trying to push the piston back down as its coming up. I think I am sorta close on my explanation. Bumping back the timing a little and all would be good. The broadband thing is a good way to tune. Where is Farnhamville close to ?
December 22nd, 2018, 03:21 PM
#6
Registered User
Join Date: Nov 2008
Location: Central Fl
Posts: 7,824
Thank you Matt, heard that about Lynn from a few.
Will check out the procomp heads and top end. Would rather retain what I have as I am guessing couple grand for a top end.
Mark, will look around for a shop with a wideband timer, and who regularly works on these older engines. Hard to find in my rural area. The small shops are either shops that just do the basic repairs on newer vehicles, and if they had experience in older engines, it was a long time ago...
Other shops are those that may build engines for the local dirt track hobbyists... Those are mainly SB chevies...
Be nice to find someone with a car dino to tune and test and be right when one drives it out the door. Will post the specs of the piston after work.
Alex
Will check out the procomp heads and top end. Would rather retain what I have as I am guessing couple grand for a top end.
Mark, will look around for a shop with a wideband timer, and who regularly works on these older engines. Hard to find in my rural area. The small shops are either shops that just do the basic repairs on newer vehicles, and if they had experience in older engines, it was a long time ago...
Other shops are those that may build engines for the local dirt track hobbyists... Those are mainly SB chevies...
Be nice to find someone with a car dino to tune and test and be right when one drives it out the door. Will post the specs of the piston after work.
Alex
Just buy a wideband and do it yourself. Doesn’t matter old school shop or not, if they have one great. If not grab one yourself and do it right. If you’re running a Qjet then you’ll have your work cut out for you. But you can still do it yourself.
December 22nd, 2018, 06:27 PM
#7
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Join Date: Jan 2010
Location: central Indiana
Posts: 5,232
If you have a Q-Jet, talk to Cliff Rugguls. He wrote a excellent book on Q-jets, and sells rebuild kits with the parts needed to calibrate the carb to your exact combination.
If the Q-Jet is stock, the engine Is most likely running lean, adding to your pinging issue. The Q-Jet is a excellent carb once set up right. I ran a Edelbrock 850 Q-jet for years. I eventually worked my car to a best 11:64, got 17mpg, all on pump gas. I have since installed a Holley sniper EFI, and have yet to duplicate the quarter mile performance.
If the Q-Jet is stock, the engine Is most likely running lean, adding to your pinging issue. The Q-Jet is a excellent carb once set up right. I ran a Edelbrock 850 Q-jet for years. I eventually worked my car to a best 11:64, got 17mpg, all on pump gas. I have since installed a Holley sniper EFI, and have yet to duplicate the quarter mile performance.
Last edited by matt69olds; December 26th, 2018 at 11:31 AM.
December 26th, 2018, 04:39 AM
#8
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Join Date: Mar 2015
Location: Farnhamville, Iowa
Posts: 332
Matt / Mark
I am running a stock Quadra jet. The core 455 had the carb on it, went to the local AC Delco store and we ordered a reman replacement carb based on that number. I tried having a local guy rebuild the original carb, then I had to drill out the primary throttle shaft and put in the new bushing to solve for vac leak around the shaft. Then ran into plugged small passages. For $250 the reman seemed like a deal. The reman came in, put it on, car instantly fired up and idled where as the other did not with the venture blockages. Carbs are out of my wheel house for work, I saw several places online to send it too, after having attempted the local guy and such.
I did the engine before finding this great forum. I admit it may benefit the running to have it tweaked to run for this application. I would be find sending the carb off for modifications if I can just bolt the finished work on and go.. Any recommendations?
I found my piston information - Keith Black 277 .030 over that has a piston head volume of +15 cc. The heads are GA heads I found are 80cc. The block was and heads were plained, as evident when we were getting the stock intake to seal. So with 95cc is that more normal range, or more lower compression?
I am running a stock Quadra jet. The core 455 had the carb on it, went to the local AC Delco store and we ordered a reman replacement carb based on that number. I tried having a local guy rebuild the original carb, then I had to drill out the primary throttle shaft and put in the new bushing to solve for vac leak around the shaft. Then ran into plugged small passages. For $250 the reman seemed like a deal. The reman came in, put it on, car instantly fired up and idled where as the other did not with the venture blockages. Carbs are out of my wheel house for work, I saw several places online to send it too, after having attempted the local guy and such.
I did the engine before finding this great forum. I admit it may benefit the running to have it tweaked to run for this application. I would be find sending the carb off for modifications if I can just bolt the finished work on and go.. Any recommendations?
I found my piston information - Keith Black 277 .030 over that has a piston head volume of +15 cc. The heads are GA heads I found are 80cc. The block was and heads were plained, as evident when we were getting the stock intake to seal. So with 95cc is that more normal range, or more lower compression?
December 28th, 2018, 07:38 AM
#9
Registered User
Thread Starter
Join Date: Mar 2015
Location: Farnhamville, Iowa
Posts: 332
If you have a Q-Jet, talk to Cliff Rugguls. He wrote a excellent book on Q-jets, and sells rebuild kits with the parts needed to calibrate the carb to your exact combination.
If the Q-Jet is stock, the engine Is most likely running lean, adding to your pinging issue. The Q-Jet is a excellent carb once set up right. I ran a Edelbrock 850 Q-jet for years. I eventually worked my car to a best 11:64, got 17mpg, all on pump gas. I have since installed a Holley sniper EFI, and have yet to duplicate the quarter mile performance.
If the Q-Jet is stock, the engine Is most likely running lean, adding to your pinging issue. The Q-Jet is a excellent carb once set up right. I ran a Edelbrock 850 Q-jet for years. I eventually worked my car to a best 11:64, got 17mpg, all on pump gas. I have since installed a Holley sniper EFI, and have yet to duplicate the quarter mile performance.
I looked up the sniper efi, impressive, but pricey. Heads like wise, i have plenty of power just want to better tune it to run on pump gas and get one can out of it.
Will search the site, think i saw some posts in the past
Last edited by 442fanatic; January 18th, 2019 at 02:30 PM.
January 4th, 2019, 06:31 PM
#10
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Join Date: Mar 2015
Location: Farnhamville, Iowa
Posts: 332
After talking with several great people on here and at shops.
Several different avenues to approach my detune issue.. Cam swap, carburetor/intake swap, carburetor rejet…
All the way to changing out the pistons to reduce the compression..
Decided to give Klotz octane booster a try, from the products website to the reviews Klotz actually raise the fuel octane by numbers rather than points. Going to tune the motor back up to 34-36 and put in a mix of Klotz and 91 pump gas. See what I get.
Several different avenues to approach my detune issue.. Cam swap, carburetor/intake swap, carburetor rejet…
All the way to changing out the pistons to reduce the compression..
Decided to give Klotz octane booster a try, from the products website to the reviews Klotz actually raise the fuel octane by numbers rather than points. Going to tune the motor back up to 34-36 and put in a mix of Klotz and 91 pump gas. See what I get.
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