Fast 78 or 90
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11 Second Club
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From: Chicago Area
Fast 78 or 90 I have a Fast 78 right now cuz I read so many posts saying the 90 was too much for a 346ci motor, and I'm an old school carb guy - ran a 1050 Dominator on my 454 and a 650 on a 350. But I see a lot of people making great numbers with the 90. Question is this - Will I make better numbers on a H/C, stock cube car, with a Fast 90 than with my 78? It's comming off this winter for heads. Don't know if it's going back on...
I would think for myself that if you have a good size cam and and better set of heads than stock LS1 you may pick up 10 horse power. I wouldnt run a 90mm Fast intake and throttlebody with the stock heads.
Thread Starter
11 Second Club
iTrader: (33)
Joined: Apr 2006
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From: Chicago Area
Yep going with a rex and ls6 heads. Still having a hard time getting gettng over the displacement issue. Just want everything to work together. Guess I need to get with times. So to speek...
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Joined: May 2006
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From: south jersey
every dyno comparison ive seen shows the 90 making more power stock heads cam or not, but the low end was slightly behind the ls6 on a milder setup ive seen 3,000 - 3,400 rpms it gave up some to the ls6 (7hp flywheel max i think) but didnt give up as much as it gained up top . the dyno started at 3,000 rpms too so i dont know how it did on the low end...
Check with Ron@Veangence Racing He'll give you the heads up on the 90/90 setup. Hes one of the sponsors ---------------------------------------------->
He uses 90/90s on every motor he does and swears by there power. Give him a chime. He also ports them to make more power then out of the box.
Check this out
https://ls1tech.com/forums/generation-iii-external-engine/574713-bling-bling-vengeance-ported-painted-fast-90mm-inside.html
He uses 90/90s on every motor he does and swears by there power. Give him a chime. He also ports them to make more power then out of the box.
Check this out
https://ls1tech.com/forums/generation-iii-external-engine/574713-bling-bling-vengeance-ported-painted-fast-90mm-inside.html
