My 383 should be done by saturday. (LS1 block, 4.000" Eagle Crank, 3.903" Mahle pistons -6cc valve reliefs, 6.125" Scat H-Beams, 230/232-.595/.585-114+4 cam, Stage 2 Patriot 5.3 heads). When my FLT Level IV 4L60E gets here, I'm gonna do the swap.

I'm gonna leave the truck intake on for about a month and dyno it and then swap to a LS6 intake and dyno it. I'm doing this to answer some questions about the LS6 intake vs. the truck intake on bigger cube motors. I'm guessing ~30rwhp on the top-end. What do ya'll think?

 

Sounds about right, maybe even more, and the extended rpm range is gonna help performance a lot.

 

I'm seriously thinking about actually waiting until I get my taxes back and doing the 90/90 FAST swap. I guess I'll just have to see how the cash flow is. The 90/90 set-up shouldn't loose any low-end on the 383 and make at least 15-20 more rwhp than a Ported TB/LS6 intake, right? So, do ya'll think it's fair to say that I could possibly make 40-50rwhp over the truck intake with the 90/90 FAST combo? Hopefully that'll put me in the 450rwhp range with a mild head/cam setup on a 383....

 

thats asking alot but doable IMO, mild is another thing tho.

I think the bigger the manifold the more low end you are going to loose. But with a 383 and most likely plenty of converter i doubt you will be lacking down their anyways.

 

unless your plan on being over 6500 no real need for the 90/90 setup

i have a LS6 intake for sale, it only gains 15hp up in that range and does lose some power down low over the LS6

 

I asked Allan Futral throught an email about the 90/90combo and that's who said no loss down low. I was suprised to hear that myself.

I'm actually gonna run the stock converter for while, with the truck intake. Until I get some tires, a yank2600 ain't gonna help me out any. Especially with my bald Firestones.

 

youre going to need a much larger stall, i got one for sale also if interested

 

You are going to need a 3000 to really rip out of the hole. Also I wouldnt waste the money on the fast setup. There are dyno charts showing that it gains very little till about 6500 like Quik said.