My engine is completely stock but eventually going to get H/C. Should I get the FAST 90mm manifold and throttle body? or the LS6 manifold?

 

^ the LS6 intake is a proven GREAT performer. The FAST 90/90 you are looking into would be best suited for F.I, n2o or large displacement. It has handy blow off ports in the intake to prevent you engine from a deadly nitrous sneeze or over boost. Also a gain for engines which require large quantities of air. .. IMO, Not worth it for just a H/C. Which H/C are you looking into, btw??

On a H/C motor, it only gains a couple HP. -See GMHTP MS4 Cam swap issue.
Huh, I stand corrected.. 15hp on the MS4 H/C swap, they also installed an SLP MAF (maybe 3 hp). Still a HUGE cam.
http://www.gmhightechperformance.com...onclusion.html

A couple people still rely on a ported LS6 intake on their 700+ HP CARS.

 

Actually Im not sure what heads and cam to get. I thought that gave you the biggest horsepower increase? what do you suggest?

 

Not really the BIGGEST HP increase.. The FAST 90/90 actually looses power on a stock motor.

Not really worth the money w/ just a head and cam. IMO.. You're fine w/ the LS6 intake at a fraction of the cost.

Lets see what other people have to say. I don't want to post *****.

 

agree with bayer, if you have aggressive h/c, stroker, bigger block (408) or f.i, 90/90. even just n20, id stick to ls6 intake.

 

I don't think I have ever heard of ANYONE losing power going to a fast 90/90 on any motor combination...

for any decent flowing heads/cam setup the LS6 will choke the motor pretty good. Even the FAST setup can't flow near what a good set of heads can, but its about the best option we have right now. There are plenty of people running bolt on only cars with FAST setups and getting good results.

just stay away from the FAST throttle body from what I have heard, get it somewhere else...

 

The FAST 90/90 is a better manifold without question. But on a stock or mild bolt-on engine gains will be minimal, and the LS6 intake is better suited for the price. If you're looking to let the engine breathe above 6000RPM, or are making 400RWHP or more, the FAST setup is something worth looking into.

Also, FAST intakes are quite easily ported, and are PROVEN to show impressive gains even on a stock engine. AFR ports these intakes quite well, and has shown gains on stock engines and modified engines alike in the neighborhood of 20-30RWHP, with more power and torque throughout the entire tested RPM range.

Stay away from the FAST throttle bodies. They have a reputation for sticking wide open, even with a rigged up additional return spring. Look into a Nick Williams TB.

Finally, its all about cost. An LS6 intake with a ported stock throttle body works very well, and can be had for well under $500 complete. The FAST 90 intake, with 90MM throttle body, with porting for the intake (HIGHLY recommended) is more than 3 times the cost of the LS6 setup.

 

Definetly the FAST 90/90 for a heads/cam setup. I gained 15 rwhp over the LS6 intake by switching to it in my old heads/cam setup and my friend gained the same.

The FAST 90/90 is a nice piece. The only thing I'd do differently is go with an LS2 TB, since the FAST TB is around $500.

 

I never had mine dynoed separate from the combination, I had in mind a 402 or a 427 at a later date so I put the fast on when I was ready to go bigger displacement I would have it. If you think you might go to larger displacement in the future then you wouldn't be saving any money by putting on the ls6 now. The only thing is that if you should go to an ls7 style head in the future the fast won't work.