Based on YOUR opinion and knowledge you have on downpipes, exhaust systems in general and Subaru's what size downpipe would you go with.

2.5" or 3".

 

Isn't it going to depend on the turbo set up? Should we just assume a stocker is in there to make it easy??

 

Say your car is stock. Downpipe is your first mod.

 

Whatever gives the most laminar air flow.

 

People vote, pelase. I am trying to prove a point or be proven wrong...

 

Hmm. Sounds like a trick question to me.

 

This is not a trick question.

 

Uhh...

From what I've read, turbos don't like backpressure...

I vote 3". :banana:

 

So vote...

 

Based on my opinion and knowledge I believe it's the 3" because bigger means more air flow meaning more power, i guess.

 

3" is the way to go!!

 

turbos dont work on back pressure like NA engines do. bigger = less lag = more fuel consumption. performace wise, 3" is the shizzle

 

i read a article written by a engineer a few years ago about backpressure and its effect on power . in the end he came to the conclusion that on turbo cars bigger is better, period.

besides the sweet sound of the boxer engines deserves nothing less than 3" so it can be heard in all its glory

 

3' are better airflowwww

 

no question...a 3" bellmouth or divorced wastegated downpipe will be superior to any 2.5" downpipe....period...