: Fast 90/92 Gains on Bolt on ls6

03-28-13, 10:59 AM
HI guys I'm along time member over on ls1tech but my searching has brought me here. I have an 03 ls6 long block swapped into an fbody. Mods now are full bolt ons, ARH 1-7/8 headers, ATI udp, ported TB, 3.90 gears, bassani td's custom air intake etc. I'm trying to do a full bolt on build and really see how far I can push it. I know swapping in a cam and porting he heads would be cheaper and easier but thats not the route I want to go.

Using googles search feature I found a couple guys on here have swapped their ls6 intake for a fast 90 or 92mm intake and tb... I'm looking to do the same and I was wondering who here has done it and what difference in power did you see. I founds a couple threads where it was done on stock ls6 motors and ls2's. Some gained 10-15whp and some lost power and torque which didnt make sense to me at all.

Thanks For the help


03-28-13, 11:47 AM
Unless you have cam and heads installed you will lose mid torque and horeepower but gain top-end horsepower.

03-28-13, 01:07 PM
I put a FAST 92mm intake + 90mm LS2 TB on my 05 LS6 and, while I didn't dyno it before and after, I'll confirm what Naf said... but the mid-range loss isn't really bad/noticeable.

Unless you live over 5500 RPM, spend your money somewhere else until you get the cam or heads.

Under the hood does SOUND meaner at like 6000 RPM though!

03-28-13, 03:20 PM
Lol thanks guys I'd think the longer runner design of the fast vs the stock ls6 would help out torque everywhere?