Sharkrider

I'm trying to get everything together for a turbo install this winter (who needs a warranty? ). I called a couple of shops that do exhaust work and both of them only offer 2.5" max diameter for exhaust piping. How much power will I lose if I use 2.5" instead of the normal 3" that alot of people use? Any other drawbacks to using smaller diameter piping?

EclipseMTL

I'm not sure how much you'll lose, but I would think it depends on the size of the turbo/amount of horsepower your going to put down. All of my coldside piping is 2", and exhaust side is catless 2.5", same trouble as you with shops only being able to do max of 2.5, but then again I'm only running a 14b. I wouldn't think it would be much at all.

Lazyshot

I don't see why a shop wouldn't carry 3" piping, but nonetheless, 3 inches is never really necessary on a daily driven car. In fact, it's usually better to have a 2.5 inch. 3 inch would make your turbo spool quicker, but with that you'll have loads of tire spin sooner.



Turbo lag = Traction.



So unless this is gonna be a race car, I would settle for 2.5.



Also, Corky's exhaust diameter chart:

iheartmyrd

it is probably because the pipe bender cant go up to 3inch ask them about mandrel.

bmxer

No mater what size you do, don't use a normal bent pipe from an exhaust shop. It'll be crush bent and besides looking like crap, will make your 2.5" exhaust flow like a 2.2" or smaller diameter. Go buy two 180 deg and one 90 deg mandrel bend. That should be enough for an exhaust that goes up and over the rear suspension.



Here is my 2.5" mandrel exhaust ... I used 2 180 deg "U" bends plus a 90 deg. Cost for mandrel bends was about $70. Its mild steel with a stainless steel tip. I have one Magnaflow cat, Magnaflow resonator and Magnaflow muffler. Sounds good and is not loud at all.