Intake Manifolds, Ls1, Ls6, and Fast.

**Lunatikgixxer** · 08-11-2011, 10:32 AM

Generally speaking if i swapped my Ls1 manifold for a Ls6, How much horsepower gain would there be? And if i swapped the ls1 for the fast, whats the gains look like there compared to the ls6?

**'02 WS6** · 08-11-2011, 11:21 AM

15-20 going from LS1 to LS6. HP gain from LS6 to FAST depends on your mods, it'll be maybe 10 if you're stock or bolt on, maybe 15 if canned, and about 20 with H/C/E.

***SMWS6TA*** · 08-11-2011, 11:56 AM

Intake Performance

LS1 <LS6/BBK<Fast 90/90<Fast 102

To get the best performance with all of these intakes it depends on TB & tuning along with Cam, Heads, Exhaust.

**Lunatikgixxer** · 08-11-2011, 04:43 PM

Ok so id probably get an ls6 intake and get it ported BUT what kind of TB is recommended for that? BBK 85mm? My cam is tsp's 233/239 cam and my tuner is arguably the best in florida. So with that probably about 25whp out of that?

**Lunatikgixxer** · 08-11-2011, 05:09 PM

i was honestly looking at the bbk intake and 85mm throttle body... I like the ls6 but it looks just like the ls1 and id want to give the engine bay a little "spice". So how much hp is though to get out of that set up?

**Firebirdjones** · 08-11-2011, 05:23 PM

The LS1 and LS6 intakes, although similar in appearance, are two completely different designs. LS6 has more plenum volume over an LS1.

Don't beat yourself up on Hp numbers. LS6 is decent for any bolt on car or even heads/cam cars. Depends on how fast you want to go. Aftermarket throttle bodies are nice, but you can port a stocker to work nearly as well for much less money if you are using a stockish intake like an LS6 that has limited throat size anyway. It's really up to you.

**cammed goat** · 08-11-2011, 05:42 PM

Most of the folks I have met with the F.A.S.T. have a completely built motor with heads, cam and forged bottom end. If you are just starting out with a stock motor, then the LS6 is your best bet.

**Lunatikgixxer** · 08-11-2011, 07:21 PM

Got cha thanks guys. I just want to get the most out of the money im going to spend on a manifold and/or throttle body set up. I understand to keep the stock TB and port it if i get a ls6 manifold. Im just trying to compare manifolds vs eachother. The LS1/LS6 Professional Products 96mm Typhoon Intake, BBK, and Holley manifolds are in a close price range as the LS6. IF i buy brand new. I can pick up a ls6 intake on craigslist for around 350.

**Firebirdjones** · 08-11-2011, 07:30 PM

I'd personally just go with an LS6 over those choices you listed. Then port the stock throttle body. Even with a mild head/cam combo.
If you really plan to go with more engine later, and are trying to squeak everything out of the combo, AND have the extra money, then I'd go with a Fast.