[Trypt]

So after a week of having a nasty exhaust leak and inhaling so much NoX, carbon and fuel vapours its starting to affect my brain functionality its time to put a new exhaust on the sierra.

Ive bought a set of extractors of fleabay, just waiting for them. they have a 2 1/4 outlet.

Should i go 2 or 2.5 inch from the extractors back?

Im pretty sure the cat is pretty much shagged so its either replace or remove, how essential is it (legislation wise) to have a cat?

After that im just going to put a reso on about half way and run it out the back.

Will i need a flex joint near the extractors?

thanks in advance

[mnemonix]

2" at the very most.
I've got a cranky 1.6 and still only run 2 1/4 inch.

If the car comes with a cat from the factory, you must retain it.
Flex joint isn't needed, they're typically used in East-West (ie: FWD) engine configuration to stop the pipe cracking from torque loading.

With just a resonator it will probably be irritatingly loud. I run with a cat and single muffler and that also is too loud.
High flow cat, 2" pipe, 12" resonator and a decent muffler would be my choice.

[Trypt]

Thanks for the insight.

My cat must be really rooted in that case. atm all i have is a cat and its not that loud at all.
I have a tin top, which is better side routed or straight back?