3.5" Catalytic Convertor

[Cubes]

Hey peoples.

For those of you who have gone the 3.5" exhaust what did you do about the cat?

I've called quite a few local exhaust shops however the largest they can get is a 3" cat.

I was told that generally they either go a twin system from the 3" cat back or a 3.5" from the 3" cat back.

Steve... What did you do when you went the 90mm exhaust? Changed the cat also?

Reason being is after the car is sprayed its getting its new motor slapped in.

[Cubes]

It was also mentioned to take the bark from the 3.5" exhaust some people use 3" mufflers and resonators with a 3.5" pipe inbetween.

Sounds dodgy to me...

[Clint32]

yeah interested to know joel, i need to do something but will probably take the easy way

[Clint32]

any yeah once you step up to 3.5'' i wouldnt go back down to 3'', dont need any resonators control the noise with your foot

[Cubes]

I'll have a good marine grade s/steel 3" for sale soonish..

bit off topic...

Hows your motor coming along clint?

[DoughBoy]

If the flow of the cat is the bottleneck in the exhaust system, and the 3.5 inch cat flows more than a 3 inch, you might find that it's still going to be the bottleneck in the exhaust.

I don't think it's that bad of an idea to use the 3.5 inch cat in a 3 inch exhaust.. .as long as ground clearance isn't an issue?

[Cubes]

3.5" all the way..

The current 3" has plenty of room every where so clearance isn't an issue.

[Bl4cK32]

If my 3" front is ok I was just gunna go Jap brand 3.5" catback and 3.5" cat. Bolt on