90mm lsx worthwhile over 78mm LSX on turbo car?
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My car is going to be set up the exact same way as the turbo car Speed inc posted numbers on a week or 2 ago. 348ci w/ GT76R turbo, stage2 heads 225/225 .581/.581 113lsa cam, LSX 78 mm intake and 78tb, etc etc. The other car made 675rwhp @10psi on 93oct and 844rwhp@16-18psi on 110 or 116oct. i think. My question is do you think would i see any noticable gains moving up to the LSX90mm intake & 90mm TB? Thanks for any input and suggestions.
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I have a 80mm bbk on a 78mm fast opened up to 80mm. I really dont think I would se much at all on my car. maybe 5-10 rwhp? But im just guessing.
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FWIW, I tested an LS1 vs LS6 vs LSX on my single turbo Formula earlier this year. Even at the 700+rwhp, there was virtually no difference at all between ANY of them. Though I did not try a 78mm vs 90mm TB, I did compare a stock TB to a ported TB and also saw no gain. Definitely not worth the money for the LSX and 90mm TB in my opinion.
Hope that helps,
Hope that helps,
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I also remember reading that the LSX manis where only tested up to 10 psi. Someone here got a full refund from LSX because he was trying to run 14psi and the manifold wouldn't take it (with out plastic welding or some kind of sealing work or something...)
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Originally Posted by TurboBerserker
I also remember reading that the LSX manis where only tested up to 10 psi. Someone here got a full refund from LSX because he was trying to run 14psi and the manifold wouldn't take it (with out plastic welding or some kind of sealing work or something...)
Mine held 20psi.......... maybe more this week
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Originally Posted by Rob Raymer
FWIW, I tested an LS1 vs LS6 vs LSX on my single turbo Formula earlier this year. Even at the 700+rwhp, there was virtually no difference at all between ANY of them. Though I did not try a 78mm vs 90mm TB, I did compare a stock TB to a ported TB and also saw no gain. Definitely not worth the money for the LSX and 90mm TB in my opinion.
Hope that helps,
Hope that helps,
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Originally Posted by TurboBerserker
I also remember reading that the LSX manis where only tested up to 10 psi. Someone here got a full refund from LSX because he was trying to run 14psi and the manifold wouldn't take it (with out plastic welding or some kind of sealing work or something...)
For the record Ive now switched to LS2 (for appearance).
Rob, thanks for the info...!
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One of our local TT guys put the LS2 intake manifold and TB on his C5 and did see a noticeable power gain. Note that the power gain over the LS6 intake manifold wasn't until after 6000 RPM. This wouldn't help me as I run a stock cam and a stock bottom-end (meaning I shift around 6000 as the boost is still growing and my cam really isn't making much above 6000 anyway) Is it worth spending $700-900 for the swap on a FI car? Not in my opinion. If you want more power turn up the boost..
Cheers,
Mark
Cheers,
Mark