How much boost is too much?
Thread Starter
Joined: Nov 2001
Posts: 8,259
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From: Valrico, Florida
How much boost is too much? Someone was telling me that my heads will lift if I run 10lbs of boost on a BB forged 346ci with ARP Studs. I disagree.. I am swapping heads for my new setup next year. 5.7 or possibly 6.0L heads and drop the compression down to 9.1:1. What do you guys think?
Re: How much boost is too much? It's the life long mystery you've stumbled upon. Until someone out there runs 20PSI we just won't know.
But I do believe that you could run pretty large boost on any motor as long as you DON'T have any detonation at all. One little inaudible detonation and it could spell disaster. All the book writing Turbo builders basically say the same thing. The boost probably isn't lifting the heads or puckering the head...its probably detonation.
But I do believe that you could run pretty large boost on any motor as long as you DON'T have any detonation at all. One little inaudible detonation and it could spell disaster. All the book writing Turbo builders basically say the same thing. The boost probably isn't lifting the heads or puckering the head...its probably detonation.
Re: How much boost is too much? Oh by the way...Harlan was running 10PSI all day without any harm to the motor other than some interesting wear on the bearing caps.
I would have to agree with your statement above. Detonation will kill any motor.
I would have to agree with your statement above. Detonation will kill any motor.
TECH Regular
Joined: Nov 2001
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Re: How much boost is too much? </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by chasgiv3:
<strong>It's the life long mystery you've stumbled upon. Until someone out there runs 20PSI we just won't know.
But I do believe that you could run pretty large boost on any motor as long as you DON'T have any detonation at all. One little inaudible detonation and it could spell disaster. All the book writing Turbo builders basically say the same thing. The boost probably isn't lifting the heads or puckering the head...its probably detonation.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I agree that detonation kills motors also, but on the ls1's that are lifting heads, i don't think all of them are detonating.
I think Missing "meat" around the cylinders and far fewer head bolts than a conventional SBC probably plays a big part.
I know detonation will do the job quick, but i think alot of the problem with these motors lifting heads with boost is from the cylinder pressure and not being able to keep it in because of the head design.
<strong>It's the life long mystery you've stumbled upon. Until someone out there runs 20PSI we just won't know.
But I do believe that you could run pretty large boost on any motor as long as you DON'T have any detonation at all. One little inaudible detonation and it could spell disaster. All the book writing Turbo builders basically say the same thing. The boost probably isn't lifting the heads or puckering the head...its probably detonation.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I agree that detonation kills motors also, but on the ls1's that are lifting heads, i don't think all of them are detonating.
I think Missing "meat" around the cylinders and far fewer head bolts than a conventional SBC probably plays a big part.
I know detonation will do the job quick, but i think alot of the problem with these motors lifting heads with boost is from the cylinder pressure and not being able to keep it in because of the head design.
Re: How much boost is too much? There are a few guys here with built motors that have boosted about 12#'s.
Rob Raymer got up to 16psi on his, but he has said the aluminum heads start to warp past 15#.
im not to sure on that though cause Harlan plans boosting past 15#'s and if anyone can do it he can.
<img border="0" alt="[Fluffy]" title="" src="graemlins/fluffy.gif" />
Rob Raymer got up to 16psi on his, but he has said the aluminum heads start to warp past 15#.
im not to sure on that though cause Harlan plans boosting past 15#'s and if anyone can do it he can.
<img border="0" alt="[Fluffy]" title="" src="graemlins/fluffy.gif" />
Re: How much boost is too much? I make no statements about my boost levels <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
I ran upwards of 10 for quite awhile. over 11 for awhile.
Had it up to 15 a couple times but was out of fuel system so i turned it down.
i'd like to see atleast 15 on a daily basis pretty soon here.
this damn day job is taking up all my useful day light that i could be spending on the car <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
I ran upwards of 10 for quite awhile. over 11 for awhile.
Had it up to 15 a couple times but was out of fuel system so i turned it down.
i'd like to see atleast 15 on a daily basis pretty soon here.
this damn day job is taking up all my useful day light that i could be spending on the car <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
