View Poll Results: Whats the best CR to have for 15-22 pounds of boost?
11:1
8
2.87%
10.5:1
4
1.43%
10:1
20
7.17%
9.5:1
59
21.15%
9:1
67
24.01%
8.5:1
95
34.05%
8:1
26
9.32%
Voters: 279. You may not vote on this poll
CR for big boost...
Most blown alky motors are 11 or 12-1.
If you ran c-16 with meth injection, it would make less power than running straight alky.
Alky already gives you the increased octane over gas and has the intercooling effects, on our blown small block we didn't even run a cooling system on the car, no radiator no water pump.
A motor with 11-1 running 22 psi is going to make more power than a motor with 8-1 running 22 psi assuming you run the right fuel and detonation isn't a problem.
If you plan to run race gas and keep things simple I would think 8 / 8.5 - 1 with 22 psi should be easy.
Last edited by RAGENZ28; Feb 12, 2008 at 03:30 PM.
LMFAO! looking at only boost and compression ratio when you are talking about safe pump gas power is so close minded it makes me laugh. You can FOCUS your attention on making a big boost number all you want, in the end it's just a number. When someone with a well matched head/cam/turbo combo blows your doors off running 7psi less, dont be surprised.
of course the engines with the most power run really high boost levels, but you can bet your *** they didn't pick their heads/cam and say "how much boost can i run" they said "how much POWER can I make"
of course the engines with the most power run really high boost levels, but you can bet your *** they didn't pick their heads/cam and say "how much boost can i run" they said "how much POWER can I make"
LMFAO! looking at only boost and compression ratio when you are talking about safe pump gas power is so close minded it makes me laugh. You can FOCUS your attention on making a big boost number all you want, in the end it's just a number. When someone with a well matched head/cam/turbo combo blows your doors off running 7psi less, dont be surprised.
of course the engines with the most power run really high boost levels, but you can bet your *** they didn't pick their heads/cam and say "how much boost can i run" they said "how much POWER can I make"
of course the engines with the most power run really high boost levels, but you can bet your *** they didn't pick their heads/cam and say "how much boost can i run" they said "how much POWER can I make"
However, you can say "its just a number", but RWHP numbers are just that, a measurement of power at the rear wheels. No one said anything about how a good H/C/I car couldn't take out a boosted stock car with low boost. In the end, the more powerfull car will win (given same suspension, gears, what not), boosted or not, and frankly I'm not sure who or why you are debating this.
No debate here, I'm just making a statement. Looking at CR/Boost only isnt the way to go about it. It doesnt matter if you are running 93 octane or 110, you need to look at the whole package before you make any assumptions about performance. even if everything else was the exact same with different cams, one car might be ok, and the other one might be a monster. or one car might be a monster, and the other one might be broke. 
personally I don't like the way a car with less than 9:1 compression responds off boost, but I'm picky.
personally I don't like the way a car with less than 9:1 compression responds off boost, but I'm picky.
I assumed pump gas for a street strip application. So I voted 9.5:1. I am waiting for the money to go turbo, but when I do it will be a 10:1 engine at max 14psi. It will probably drive it on 7psi and E85.
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I voted before I read the post. what a noob mistake. My game plan for a turbo build is 10:1 but 10psi and E85. I still feel 9.5:1 is good cr for 15-22psi boost and race gas. Im sticking with my original answer.
That's because the majority of people are scared to risk thier engine, they vote safe not best. There is no way around the issue, more compression is going to make more power regardless of how much boost you run. You can say boost 30psi on a low cr and I say boost 30psi on high cr and see who wins. It may not be as safe but the more power you make the more at risk you are regardless.
That's because the majority of people are scared to risk thier engine, they vote safe not best. There is no way around the issue, more compression is going to make more power regardless of how much boost you run. You can say boost 30psi on a low cr and I say boost 30psi on high cr and see who wins. It may not be as safe but the more power you make the more at risk you are regardless.
The poll is for "What CR for big boost on race gas", not "Whats the best CR for the most power". And the results clearly show that the vast majority of us disagree with you that its a good idea to run high CR with boost even on race gas.
There's no doubt you'd make more power, but you also might grenade you're motor, which to most of us isn't worth the extra few unlreliable ponies, and thats why we disagree with your opinion on this.
You're not saying anything new. You're just saying the same thing as others debating on here louder.
The poll is for "What CR for big boost on race gas", not "Whats the best CR for the most power". And the results clearly show that the vast majority of us disagree with you that its a good idea to run high CR with boost even on race gas.
There's no doubt you'd make more power, but you also might grenade you're motor, which to most of us isn't worth the extra few unlreliable ponies, and thats why we disagree with your opinion on this.
The poll is for "What CR for big boost on race gas", not "Whats the best CR for the most power". And the results clearly show that the vast majority of us disagree with you that its a good idea to run high CR with boost even on race gas.
There's no doubt you'd make more power, but you also might grenade you're motor, which to most of us isn't worth the extra few unlreliable ponies, and thats why we disagree with your opinion on this.
Thats all fine and dandy, I hope everyone continues to go that route because I like to win races. You guy's can have your boosted cars that last 10 years and lose to mine for the first 5 years. Then when it gernades I'll build it again and continue to win for another 5 years. I would rather win for a short amount of time than lose for a long period of time. I'll lose to the guy that has an engine that only lasts 1 year so on, so on. How far do you want to take it, some guys rebuild the engine every couple passes. Everyones goals are different so there is no correct answer to this poll it's just how fast do you want to go. High compression is better for more power. I'm done.
I would rather have a high boosted beast that I know is reliable than drive something that I don't know if it will make it home without blowing the motor. And this is just where you and I (and the rest of the majority who voted for the lower CR) differ in opinion.
Thats all fine and dandy, I hope everyone continues to go that route because I like to win races. You guy's can have your boosted cars that last 10 years and lose to mine for the first 5 years. Then when it gernades I'll build it again and continue to win for another 5 years. I would rather win for a short amount of time than lose for a long period of time. I'll lose to the guy that has an engine that only lasts 1 year so on, so on. How far do you want to take it, some guys rebuild the engine every couple passes. Everyones goals are different so there is no correct answer to this poll it's just how fast do you want to go. High compression is better for more power. I'm done.
Hey bro-STFU!!!!!
Let everyone build there stuff according to the pole-if not there will more an more faster cars out here!
I don't know how else to say it. The poll is for what the poll says, "what CR for high boost with race gas", and the results are obvious. If the poll was for most power, then I think all of us that understand how things work would have selected a higher CR.
I would rather have a high boosted beast that I know is reliable than drive something that I don't know if it will make it home without blowing the motor. And this is just where you and I (and the rest of the majority who voted for the lower CR) differ in opinion.
I would rather have a high boosted beast that I know is reliable than drive something that I don't know if it will make it home without blowing the motor. And this is just where you and I (and the rest of the majority who voted for the lower CR) differ in opinion.
I know, I'm not even sure why I'm trying to explain myself. I'd rather everyone follow the pole. I'm glad I'm not the only one that understands though.
I know what you mean bro-for example a friend of mine got talked out building his forged 347 at 10.1(they built to be 8.8.1)-then he wondered why he couldn't make the same power as I did cause he couldn't push the blower any further. So he got fed up and swaped over to smaller CC heads and picked up over 50 rwhp with ALOT less timing and fat tune. He's happy now and says the throttle response is sick!
