Right now, i am thinking about doing either the exhaust or ECU flashing. Which mod would give me the most bang for the money?

 

What part of the exhaust? Headers, Cats, Mufflers, or the entire system?

 

I was thinking of replacing just the mufflers.

 

If you want sound, then do the Gundo Hack, mufflers will not give you any noticeable gains.

As for software, my past experience with it on my first 997 provided no improvements either, however a number of people seem to have a different opinion. Softronic and EVOMSit seem to be the most popular flashes (my previous flash wasn't either of these).

 

Do the cats if it's the exhaust. Do coilovers if you can only pick one thing overall. (IMHO). And sneak in sway bars when you do it (I know, that's two!).

 

If you can only pick one or the other, would it be headers or hi-flow cats? Just by looking at them, the stock headers look awfully restrictive.

 

I did cats + gundo hack and couldn't be happier

 

I second the suggestion of moving to coil overs as the first MOD. It was the single best mod I've completed. CATS, headers and BMC Filter next, then the software flash to take advantage of the better breathing.

 

I would start with Mufflers or Intake. I started with intake then quickly added aftermarket mufflers. I will be doing the ECU next.

The sound difference is worth the funds.

I'm a big OEM guy and don't want to alter the look of the original car. Great thing is you can hear but don't see the change.

 

While we all agree the stock headers look more restrictive, there has been no evidence that shows that X51 headers or other after-market headers, all of which look better, actually perform any better than the stock headers. The only exhaust item that apparently affects performance is high flow cats. Even then I'm not sure you would see that "imrovement" translate into anything meaningful. Even a 10 hp increase is barely detectable in these cars. But the cats do sound great.

 

Get the Tubi system, you will not regret your decision.

 

If you want (albeit modest) improved engine performance, cats are the best bet. But it's modest. Mufflers improve the sound but don't do much (or anything) for incremental power. The headers are somewhat restrictive, should be replaced if you're doing the whole exhaust thing, but should not be first on the list (my POV).
A lot of this depends on whether you're a power guy, or a handling guy. I'm more of the latter (though I've ultimately done both types of mods). But if you're like me, the suspension upgrade is key. And regardless, the suspension change gives a (very subjective) more substantial sense of improvement than any other single thing (well, perhaps a SC, but that's 'beyond the scope of the course).

 

i have the gundo hack done and want it a bit louder. does your cats makeit louder or just changes the sound up a bit or both...thanks

 

The cats made my PSE in loud setting sound a lot louder, in a husky way. I believe the gundo hack sounds about the same as PSE in loud mode, so the cats will make yours louder.

 

I would suggest Headers & 200 CEL Cats. As mentioned earlier mufflers don't add much HP. But replacing the Stock Headers & Cats should give you a nice bump in HP.

AWE has a special, I think it will continue until the end of the month. You should check it out! I have AWE Mufflers & 200 CEL Cats on my car, they sound great!