View Full Version : LS6 to Fast 78mm?????? yes or no

04-18-2012, 07:26 PM
A friend of mine offered me a fast 78mm at a lower price than others posted, what i want to know is, if it is better than the ls6 or is it flat out the same??? the setup aint to big on the car that's why i don't want to go bigger with a 90+, what do you experts think besides the good looks of a fast over the ls6

02 m6 with prc stg 1 heads, 224/224 112 lsa .591 cam, p-p TB and all the other goodies

04-19-2012, 01:06 AM
I'd save for a larger one. A 90, 92, or 102 will work fine on any sized motor as long as your air requirements aren't more than the intake can flow.

If you plan to go bigger in The future, You will quickly out grow the 78.

But if you plan to stay where you are with the setup, a 78 will be an upgrade from the ls6...But not a tremendous amount.

04-19-2012, 02:23 AM
just bought one myself, the 78 and the 90 have the same size runners. only the opening is different. plus if you can find a 90 shell you can put that on your 78 base. bare essential racing will port them for 200 bucks for even more of a gain.

04-19-2012, 09:58 AM
I would definitely get it. The majority of the power gain is from the runners, not the 90mm opening.

04-19-2012, 11:15 AM
yea i was thinking their is no possible way it can hurt power and its gonna look real nice, so i went ahead and got it gonna put it on today and its off to the dyno and see what happens, thanks for the help guys