2 1/2 or 3'' spintech exhaust

[93cobra12]

i got a 331 w/ bbk long tube headers, v2-sq trim.. I know my motor can use the 3'' x pipe , but im trying to decide if i want to use the 2 1/2 to create more velocity? whatta ya guys think?

which would serve a better purpose for my motor.. this is for the spintech exhaust.. thanks !! combo below

331
185 afr heads
crower cam
tfs track heat intake
v2-sq stock pulley
bbk long tube headers

 

[2NDTIME]

I have read that the 2 1/2 is not a restriction till around 500hp. If you had free flowing spintech mufflers I don't think it would be a problem.

Or put some 3" cutouts before the mufflers for track duty.

 

[ka0tyk]

i agree that 3" could be a little too big and hurt you on the backpressure and low end torque... on the other end it would help with high end hp... its a win/lose situation...

 

[90mustangGT]

Going from a 3" system into a 2.5" system would cause nothing but more backpressure, it would make more sence going from 2.5 into a 3" catback. Just go 3" all the way.

 

[JadeFalcon]

3", I run 3" spintech exhaust and it sounds great and I gained low end power from a stock h-pipe. PEople will always seem fit to argue you loose low end, but with the amount of high end you get from the change that dosent even matter.

 

[ironmedic]

i agree with jade, im running spintechs and i love them! i feel like i lost torque but i gained a nice sound and more HP somewhat.

 

[93cobra12]

I do have the bbk long tube for torque and an aluminum flywheel with 373 gears plus a 331.. I dont think my low end is going to be hurting that much.. I got a nice cam for that set up... So you guys think 3'' will do me good huh...

Anybody running a similiar combo?

 

[93cobra12]

hey Iron, what is ur combo? what size exhaust do you have?