I have Stillen - can’t get much louder as far as exhaust goes... but the primary question is do you think it's worth it to do cats without headers?... what difference do you think I would notice having cats no headers vs cats and headers?...

Thanks for your responses BTW...

 

Wondering what, "buzz when cold" means?

 

are headers worth it?... on a grand scale of things, no bolt-ons are really worth it. but will free-flowing cats give you more mid-range and high-end power? - yes they will. if i were you, i would not get just cats alone - get headers and cats, in order to combine the labor fees. then you'll have complete exhaust system and you won't have to touch it again.

 

on mid-throttle acceleration (city traffic), around 3k rpm, there is a buzzing noise that adds to the exhaust note. it actually does not sound bad - a bit more exotic, if you will. a bit like a porsche sound. but after car warms up (few minutes), the buzzing is gone.

 

How much is the L-Spec? It only raises the rpm's to 7100 and removes the top speed limiter, correct?

 

i paid $500 for sedan F-spec, then got L-spec reflash because it pinged, and got $150 back. coupe is $100 more.

yes, L-spec only raises REV limit to 7100, removes top speed limiter, and also makes throttle 100% open at WOT all the way to red line (normally it begins to close - up to 20% closed at redline at WOT).