FAST 90mm intake question
Thread Starter
Instructor
Joined: Feb 2010
Posts: 172
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From: Louisiana
FAST 90mm intake question
Im new to the whole corvette scene so please excuse any ignorance. I got a 99 with headers, small cam, pulleys, ls6 intake, not too sure what heads, and some other little things. I found a ported FAST 90mm intake manifold and throttle body for a decent price and wasnt sure if it was worth the money or if the stock ls6 manifold would do the job just as well.
Safety Car
Joined: Oct 2007
Posts: 3,903
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From: You know your drunk when you swerve to miss the tree then you realize its your air freshener! Covington Ga
You would pick up some with the 90mm. It has alot to do with the type of heads and the cam you have. The LS6 does flow pretty dang good.
Drifting
Joined: Feb 2006
Posts: 1,585
Likes: 15
From: New Hartford IA
You'd gain some up top, but the smaller the cam you have the less to gain IMHO. I gained 20whp from my own lightly ported ls6 to my own fully ported fast 90 on my 383. It's probably nothing you would feel on a mild setup.
Drifting
Joined: Feb 2010
Posts: 1,310
Likes: 99
From: Arlington Texas
You will gain power from a 90/90 setup. On a stock bottom end and not knowing what heads you have I would say 10-15 rwhp. A big cube motor (400+) can see gains of 20-35rwhp. The fast is generally not cost effective. Yes you will have gains but alot of people just dont think its worth the cost.
If the price is good enough and you want more power then do it IMO.
If the price is good enough and you want more power then do it IMO.
Thread Starter
Instructor
Joined: Feb 2010
Posts: 172
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From: Louisiana
yes the heads have A LOT to do with it, but like I said I have no idea what heads are on there. Im working on trying to get more details but just as a worst case scenario about what gains would I see with the stock 99 heads.
Safety Car
Joined: Oct 2007
Posts: 3,903
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From: You know your drunk when you swerve to miss the tree then you realize its your air freshener! Covington Ga
Not that much on the stock heads. Whats the casting number on them or is there one? If they are stock they should be 85x not sure what the last number is on them I think its 858?
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