Perrin catback exhaust 2.5' or 3.0'?
 

Hi there, would like to ask you guys which one will you select when making purchase on cat back. also i would like to know for perrin they have only release 2.5' overpipe does that mean it only support for the 2.5' cat back system or it will suit the 3.0 ' as well? thanks a lot.

2.5" if staying NA, 3" if going turbo.

And I'm guessing they can't fit a 3" over pipe in there? Either way, I don't know of any headers that have a 3" exit so it's ok to go from 2.5" to 3"

Flanges for all exhaust piping on the 86 are all the same. So you can have a 3" outlet on a header and pair it with a 2.5" or vice versa 2.5 to 3" you just have use a different gasket.

I have had both 2.5" and 3" Perrin resonated CB's. If your just planning on just getting a CB with no other exhaust modifications then I would go with the 3", it has a deeper tone to it and according to Perrin it out performs the 2.5". Once you add a header the 3" gets super loud.

not 100% sure on this...but i heard if you go with just 3" CB (staying NA), you lose a bit of bottom end?

I went with the 2.5" CBE, and I do not regret it at all. It's just loud enough for me without being obnoxious. I now have an addiction to tunnels and parking garages as well. The nice thing is if I do want it to be louder in the future, I can always add a front pipe to the setup.

I am thinking not going for turbo. but do we need to do a dyno tune in order to use this exhaust? will we see any power increase or torque without adjusting the ecu??

No tune needed. Not much gains to be had from a catback exhaust anyway, maybe a few hp.

Just wondering whats CB or CBE mean thanks...

I see but the noise and tone are better than oem?? will that be a problem to install before the car brake in period??

Cat Back exhaust. Having a 3" CB will not effect low end torque or effect your break in period whatsoever, now once you have a full 3' with a aftermarket performance header that's a different story. I would just stick with the 2.5 and have more options down the road without worry about it sounding like total shit.

and if your looking to stay NA this is the best bang for the buck, welcome to the Forum!

Open Flash Tablet (tuning software) $495
Drop in Filter $50
Open Flash Header (Unequal length) $515 plus gasket kit $50
Tank of E85 $45~$50
Load OTS E85 stage2 map - free

Yes, it will definitely sound better than stock. I installed my catback before I hit 200 miles ;)

If no turbo, stay with 2.5". Any bigger, and your exhaust will start to sound raspy/buzzy. Our engines are too small

Perrin catback exhaust 2.5' or 3.0'?
 

I went with the Perrin 2.5" overpipe, berk catted 2.5" front pipe, and Perrin 3" resonated cat back.

I absolutely love it!

Still waiting for the OFH to be delivered. It's a long wait.

So I assume I can connect my 3" frontpipe to a 2.5" midpipe for a 2.5" diameter exhaust. Will my garage have the flanges on hand for fitment?

I don't think the conventional wisdom of 3.0" = turbo, 2.5" = NA should be quite so sacrosanct. Based upon my research, the difference to be expected in power might be on the order of ~3% at 300 horsepower. If you want power and peace & quiet, go 2.5". 2.5" is enough for these engines, even with forced induction. OEM's do it all the time, and they're not stupid.