Best 2.5' exhaust system for i6?

[ST]

As the title says, just wondering which would be the best to go for. Mostly from a performance point of view.

I know there are a few threads on exhausts at the moment, but none of them have answered this question (from my quick overview).

[JC]

Best in terms of performance is anything that is mandrel bent. 2.5" is plenty big enough for an I6 (even a mild V8), so it's not like one system is going to outflow another system by a huge amount. Straight through mufflers are better for air speed through the exhaust, and probably outright power.

There are a number of brands that you can get - lukey, redback, genie, etc. Redback fitted is under $400; don't know about the rest, but ring your local exhaust place - they may even have developed a "custom" mandrel bent one at a reasonable price.

You will need to run the rear resonator on an auto if you don't want any droning, and it doesn't make a lot of difference, if any, to power output, as resonators/hotdogs are usually straight through mufflers, just small ones.

Interms of extractors, the Pacemaker 4499s are a good mid-priced system suitable for all I6s - you will see an increase in torque for any I6, though the VCTs tend to suffer a small power loss with these compared to the 4480s, but 4480s are not very good for non-VCT, unless the car is heavily modified (you lose too much torque due to the larger primary pipe size). Extractors should be around, or under, $600 fitted (except the 4480s, which are closer to $900 odd).

Having said all that (especially the bit about the VCTs), Zhodak just had 4499s, a new 2.5" cat and redback (we think) 2.5" mandrel bent system fitted to his 2000 model AU2 Ghia (VCT) auto, and the power increase, especially down low, ie from take off, is amazing. It takes off better than his sister's Porsche Boxter (but naturally would lose out after 40km/h). It is easily the best Auto I6 I have driven in terms off outright launch and kick down response, and this is one that doesn't have a Hi-stall in it.

[stiddy]

I went and priced a cat back 2.5inch system for my sisters EF.

Carline mufflers - $440 its half off the shelf and half custom. I thought that was a rich.
I bought Difillipo extractors, $625, havnt put them on yet, sorting out a gearbox issue at the moment.