Higher boost with lq9's w/ D1sc

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Jan 31, 2007 | 12:29 PM

02NBMFormula

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From: Jax, Fl

Higher boost with lq9's w/ D1sc

I plan to put a d1sc on this summer and run it around 8psi, its through a stall auto so im guessing around 420-440 rwhp. i was wondering if switching to lq9 heads, to get lower compression, to going to a little higher boost would be safe. id like to get around 480-500 rwhp but im not too sure how safe it would be. (550rwhp is around the stock blocks limit, correct?) i understand that would need a really good tune. this is a daily driver with 50k miles. also what boost would be safe with that head combo? would it be as safe as 8psi on stock heads?
thanks in advance.

Jan 31, 2007 | 12:32 PM

98turbls1

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From: Central Oklahoma

8psi is perfectly fine...Just make sure that there is no Knock Retard if you're tuning and that your AFR is somewhere around mid 11.x @WOT ...

Jan 31, 2007 | 09:11 PM

fenix999

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From: Miami, Florida

what he said, those heads should make the motor run real nice and safe while still giving you nice power all around. Just whatever you do be prepared for worse case scenario and save up about $600 for pistons just in case you fry one or more of the rings and you have to rebuild. Just my .02 good luck with it though it should hold for a very long time the way ur thinking about doin things

Jan 31, 2007 | 10:47 PM

52172

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From: Buellton Ca

you can run more boost with the lower compression and still have the same cylinder pressures. So the answer to your question is yes.

Feb 1, 2007 | 05:14 AM

EPP

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Patriot LQ9 stage 2 heads work great on these engines, and are affordable.
We use them on many of our builds, such as in this Corvette. http://www.exoticperformanceplus.com...Car.php?car=40 Bob

Feb 1, 2007 | 06:19 AM

lmt0705

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From: buffalo NY

you have to be careful with the stock pistons, trust me I know from experience. I was making just under 500 rwhp and I busted 2 pistons in my stock motor

Feb 1, 2007 | 07:21 AM

rufretic

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Quote:

Originally Posted by lmt0705

you have to be careful with the stock pistons, trust me I know from experience. I was making just under 500 rwhp and I busted 2 pistons in my stock motor

Who tuned it?

I'm planing on making around 600rwhp with a good tune. I'm pushing my luck but with 500rwhp and a good tune, the stock block should last. I am also using lq4 heads for extra safty. I don't think you want to add more boost though. The way I understand it, you can make the same power with less boost. Ex. stock heads+8psi=495rwhp and lq4 heads+6psi=495rwhp. At least thats the way I understand it, it's safer because you can run less boost but still make good power.