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Originally posted by dynoman14
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Roy,
When running a stocker engine with minimal rules on RPM the way to win is to turn more than the next guy!!! More power strokes to the ground can be accomplished with any set of heads. Compression is almost a not even a consideration if you know what you are doing.
I have asked many times how did they get 725hp from a 9:1 - 358" w/390 carb? I have a couple of the engines sitting in the shop collecting dust just in case I want to go back Super racing on pavement if they ever get the purse about $5000 to win for 250 laps.
The cam you need for stock heads moves the valve off the seat really fast and accelerates the lifter as quick as possible. Big lift at .100", .200", and .300" lift. With the area these cams provide it is almost like porting the heads as the engine has access to more air early on in the valve event and in some cases the flow numbers on a stock head with these cam lobes will outperform ported heads with regular cams. That being said I would say 250*-258* around .450" lift ( would like to flow heads to make sure ) on a 104* LS stick, with the intake installed at 100*. This cam should rock your world and everybody elses and has 10-20% more area under the low-lift curve than anything out there I have checked to date. This thing hits so hard it will sound like the engine has 16:1 compression. Cams take about 2-3 weeks depending on how busy I am, each one gets Cam Doctored and measured for perfection.
I have a series of lobes that I R&D'd about 5 years ago when we ran lift rule engines in Hooters Cup. These lobes run as high as 9500rpm with minimal harmonics and in your case with your heads you should be able to run 7500rpm. You will need to purchase a Super Victor intake and bite the bullet if you want to make big power with your 882's. Don't mill them any as you don't want to have to pull that compression braking around with a stock head that does not flow air.
Low airflow, hi-compression engines starve the engine for fuel under deceleration when the throttle blades close. This is even more exaggerated with a 2-BBL even though you will be running a 500CFM. In the old days, that's why they burned up engines, when Nascar ran 16-17:1 Compression they would burn engines up on re-starts. Well after about 2 years of trying to convince them it was under deceleration rather than acceleration. I finally got a couple customers to listen and then they caught on. That is one of the big reasons you need a manifold with some volume.
You can pm or e-mail me if you need further info or help.
I know all of my loving fans and post jumpers are going to reply, now I am in the cam business but I just had a 3 year non-compete, non-disclose agreement expire Jan.1 2011. ( related to camshafts / lobe design ). I have been in that business since about 15 years ago when I was an operations manager at Reed Cams.
The Comp 651 is a nice shaft for an off the shelf piece. Those are pretty extreme lobes for valve control on the top end and that is where my stuff differs from most. I am radical about getting valvetrain harmonics eliminated. My lobe is about 5% bigger at .050" with almost 20% less lift. When you do the math the head flow increases almost 15% thru the lift curve making a 180cfm head flow
( approximation on stock 882's ) almost 210cfm ( +30cfm ) and still maintaing low lift to keep from killing valves, seats and springs.
Anybody that checks leak-down regularly knows how important the valve seats are to maintaining long term power.
You can also check with any knowledgable engine builder around and +30cfm on heads can produce almost double that in Engine HP. On crate heads I flow them and have dyno'd enough of them to know that +10cfm on the heads is 20HP. The same thing applies to almost every race engine around as a Cup engine needs about 400cfm heads to make 800HP.
Crate heads flow 210-235cfm, better hope you get the good ones.
These numbers are from my SF-600 bench at 25" and is probably different from most folks but I have been using it for 30 years without a problem.
I still think the biggest gain you can make on any race engine is having your carb and ignition system matched to the accleration curve of the fuel you are using. Pump gas A -vs- Pump gas C has a 20hp difference every time I test it and I can tell a difference when I run either one in my Suburban.
When running a stocker engine with minimal rules on RPM the way to win is to turn more than the next guy!!! More power strokes to the ground can be accomplished with any set of heads. Compression is almost a not even a consideration if you know what you are doing.
I have asked many times how did they get 725hp from a 9:1 - 358" w/390 carb? I have a couple of the engines sitting in the shop collecting dust just in case I want to go back Super racing on pavement if they ever get the purse about $5000 to win for 250 laps.
The cam you need for stock heads moves the valve off the seat really fast and accelerates the lifter as quick as possible. Big lift at .100", .200", and .300" lift. With the area these cams provide it is almost like porting the heads as the engine has access to more air early on in the valve event and in some cases the flow numbers on a stock head with these cam lobes will outperform ported heads with regular cams. That being said I would say 250*-258* around .450" lift ( would like to flow heads to make sure ) on a 104* LS stick, with the intake installed at 100*. This cam should rock your world and everybody elses and has 10-20% more area under the low-lift curve than anything out there I have checked to date. This thing hits so hard it will sound like the engine has 16:1 compression. Cams take about 2-3 weeks depending on how busy I am, each one gets Cam Doctored and measured for perfection.
I have a series of lobes that I R&D'd about 5 years ago when we ran lift rule engines in Hooters Cup. These lobes run as high as 9500rpm with minimal harmonics and in your case with your heads you should be able to run 7500rpm. You will need to purchase a Super Victor intake and bite the bullet if you want to make big power with your 882's. Don't mill them any as you don't want to have to pull that compression braking around with a stock head that does not flow air.
Low airflow, hi-compression engines starve the engine for fuel under deceleration when the throttle blades close. This is even more exaggerated with a 2-BBL even though you will be running a 500CFM. In the old days, that's why they burned up engines, when Nascar ran 16-17:1 Compression they would burn engines up on re-starts. Well after about 2 years of trying to convince them it was under deceleration rather than acceleration. I finally got a couple customers to listen and then they caught on. That is one of the big reasons you need a manifold with some volume.
You can pm or e-mail me if you need further info or help.
I know all of my loving fans and post jumpers are going to reply, now I am in the cam business but I just had a 3 year non-compete, non-disclose agreement expire Jan.1 2011. ( related to camshafts / lobe design ). I have been in that business since about 15 years ago when I was an operations manager at Reed Cams.
The Comp 651 is a nice shaft for an off the shelf piece. Those are pretty extreme lobes for valve control on the top end and that is where my stuff differs from most. I am radical about getting valvetrain harmonics eliminated. My lobe is about 5% bigger at .050" with almost 20% less lift. When you do the math the head flow increases almost 15% thru the lift curve making a 180cfm head flow
( approximation on stock 882's ) almost 210cfm ( +30cfm ) and still maintaing low lift to keep from killing valves, seats and springs.
Anybody that checks leak-down regularly knows how important the valve seats are to maintaining long term power.
You can also check with any knowledgable engine builder around and +30cfm on heads can produce almost double that in Engine HP. On crate heads I flow them and have dyno'd enough of them to know that +10cfm on the heads is 20HP. The same thing applies to almost every race engine around as a Cup engine needs about 400cfm heads to make 800HP.
Crate heads flow 210-235cfm, better hope you get the good ones.
These numbers are from my SF-600 bench at 25" and is probably different from most folks but I have been using it for 30 years without a problem.
I still think the biggest gain you can make on any race engine is having your carb and ignition system matched to the accleration curve of the fuel you are using. Pump gas A -vs- Pump gas C has a 20hp difference every time I test it and I can tell a difference when I run either one in my Suburban.
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