Hi,

I have a fg xr6 turbo.

Looking at getting an x-force cat back exhaust.

deciding between a twin 2.5" cat back or single 3.5" cat back.

hoping someone can help me with a few questions:

1. Does anyone know which exhaust is louder; twin 2.5" cat back or single 3.5" cat back.

2. Will a re-tune be required.

3. Which exhaust will make more power?

I have had both systems on my ba!

The twin 2.5 was soft and I removed the middle muffler to make it louder! Supported 320rwkw

Went to 3.5" sounds nice as is and is good for my 385rwkw.

Catback systems are fine but if you touch the cat you will need a tune.

3.5" is the better one to go for if chasing power....

I wish I went a 4" instead of twin 2.5's

3.5 inch is a clear winner. Also for some reason turbo cars respond better with a single system. Veloscity I suspect.

Cheers

Cummon wiki u got better than that

my twin 2.5 mild system is supporting 365rwkw...

Get a custom 4" or gtfo

twin 4"

Twin 5"

I have had both systems on my ba!

The twin 2.5 was soft and I removed the middle muffler to make it louder! Supported 320rwkw

Went to 3.5" sounds nice as is and is good for my 385rwkw.

Catback systems are fine but if you touch the cat you will need a tune.

3.5" is the better one to go for if chasing power....

There are guys running twin 2.5 inch x-force systems that have over 450 rwkws.