voted before reading the post lol =/ 2.5-3

 

Even most V8's do fine with 2.25" piping. There's really no need for any more unless you're going turbo.

 

For my quad exhaust, 2.5 inch piping was recommended for the midpipe, the JUN system arleady comes with 2.5, and also the TK HFC is also 2.5.. but i think for a single tip or dual tip, 2.25 is fine enough.

 

I want to see dynos comparing 2.25" and 2.5" on the 2.0L and 2.4L. Did Solo Performance make any dynos on the MR setup?

 

IMO 2.25 to 2.5 on both exhausts will only really differ at most 2-4 hp unless its paired with a tune.
The most noticeable difference between the two would probably be noise.

 

I'd bet it's not even that much.

 

I'm getting either a tune or the RRM piggy back in July since I should have all the bolt on parts done by then. I want it a little on the quieter side since it'll have headers and only a high flow cat instead of two factory cats.
So which one will yield me with the 2-4 more, 2.5"?

RRM, remember doesn't make an exhaust, says that 2.25" is the best for our world engine.

 

Most of the NA tune Lancer guys I talk to and meet have 2.25" piping. I ran 2.25 on my SX4 before the turbo and 2.5" after.

 

That's what I think is correct punksmurph

 

damnit, i just installed 2.5 piping from the stock resonator back to an aftermarket spinntech muffler. Fml. That means i lost some torque? :'(

 

It's .25" larger than stock which is going to breathe better BUT in turn, you most likely lost some torque and back pressure. It could also be the reason why your new Spintech muffler sounds the way it does (however, it could also be the stock resonator causing this as well...). To me, unless the engine is modified, the extra .25" isn't worth it since our cars were made to run with 2.25" exhaust. Please correct me if I'm wrong.

 

Pretty sure stock is 2 inch, so the half inch from 2.5 makes a big difference...

 

Well I'm going 2.5" from the exhaust manifold back. Hoping the the header will be 2-2.25" whenever it happens.

 

I really need to update it as many things have changed.

 

Updated my garage for the troll!