A ported Fast90 can be had in the $900 range and has shown 0 gains and even some losses on a stock H/C LS1/6 motor. However, we've seen this intake excel in those extreme 500rwhp stock cube applications. At what point is this intake cost effective? Would it be worth it with a simple ported 5.3L or LS6 head + TR228 cammed set up? 20rwhp would be the ideal breaking point for me.

 

you are better off withh a plain FAST 90/90 set up

 

Yes it would be beneficial

 

I believe that Vengance showed their porting to gain somewhere around 7-10rwhp on cars with H/C. On smaller cams like the hotcam I don't think it would gain much. But the TR228 is decent. With heads you will see some gains over the stock 90/90. On ebay you can get a stock FAST intake for about $740 shipped. So you have to ask yourself if $160-$200 more for a ported is worth maybe 5 or 6rwhp.

Because to get the full benefit would mean better flowing heads than those you listed and a bigger cam. Personally if I was getting the set up you mentioned and I was on a budget, I would spend that extra cash on pushrods and an LS2 timing chain---or--a pulley.

 

To be specific, the heads I am looking at are the TSP stage 2.5 heads (5.3L).
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Intake Flow Information:

.300 208
.400 257
.500 290
.600 312

The PRC Cylinder Heads Feature: Brand New GM 5.3l Based Cores, Smaller Combustion Chambers For 10.75:1 Compression, Stainless Steel 2.04"/1.575" Valves, PRC Double Spring Kit Complete With Springs, Titanium Retainers, Seats, & Seals
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They look to flow pretty well. Maybe I should look into a larger cam? I'd like to benefit from an intake, if possible. This is going on an a 03 Z06, btw.

 

The Fast 90/90 is horrible dollar to HP ratio, if yrou trying to squeek every last HP out of your combo, and you can easily afford the money then go for it, but if your not the LS6 intake is awesome and you can spend that 1200$ somewhere else.

 

just curios to the ney sayers of the ported fast how little of a gain did you get? Im heads and cam with aported fast and can give results on my experience with it to the original poster of this thread.When i was just cammed (tr224/112 in an A4)with an ls6 intakeI put down 350rwhp.I added TSP stage 2.5 5.3L heads and a ported fast and now at 417rwhp 407rwt.Thats a 67rwhp gain!!!!.When i called TSP about what gains i would get with the heads in an A4 Jon said 35-40 ,and when i spoke with Ron at Vengeance of what i would get with his ported fast he said 25-27rwhp in a H/C .I got 67rwhp between the two.So to me aported fast is worth 25-27rwhp on aheads cam combo

 

Those are good #'s and you are correct, but you are missing out on one thing, the 25-27rwhp you got was not from the port alone. 15-20 of those rwhp came from the fast intake in its stock form. The extra 5-12 hp you got came from the actual porting.

 

Good info.