Here's the OEM '02 STS.....Imagine you're looking at the top from through the trunk floor.......the 2" to 2 1/4" pipe from the cat has a small zig aft of the resonator.....the Y necks down to 1 3/4" in a couple of bends. IMHO, spend the grand and do a CORSA. Comes with a life guarantee and won't hum you out of the car. If you insist on building the system from scratch, make the left exhaust tip completely phony and run a 2 1/2" or 3" pipe from the cat/resonator back to the right fender well area and split it out to two side-by-side 2 1/2 pipes through a dual-pipe muffler with chrome tips in the right exhaust area. A Y pipe is for looks, nothing else......
Thank you for the pic of the rear section Submariner. I like to plan out before taking my cars to my exhaust guy. I don't really like corsa as they droned the heck out of my corvette, so that's why I am looking to do it custom again..
And to CadillacSTS2003, that you for another smart-azz and totally useless post. The picture on the Corsa site is only of the catback exhaust they sell, not how the stock routing goes from the engine back. :thepan:
Anyone ever disassemble a stock muffler and see what the chambering/routing is like inside? How open/restricted they are?
:thumbsup: ^^^ Back in 11/06 I did the CORSA thing to my '02. Nice, easy installation. I MIGHT have gained a couple of tenths MPG, and MIGHT have gained something at redline WOT. Otherwise, it's a wash. Looks OK, sounds great when you get on it, quiet at cruise, but it will take 1,455,000 miles of gas to amortize the savings in fuel. It may scare a riceburner from the rear, BUT.....we're messing with a highly tuned engine that makes less horsepower than a 1964 Chevy with a low-mod 283. Face it....a 280 CI DOHC is a tweaky engine that is tuned to the max as is.......!!!!! ('03 et.al. ...... let the questioners wade through the archives and tech articles. Don't get your blood pressure up over the neonlight newbies....) BTW....The inside of the stock mufflers looks like a walk through the maze at your local amusement park.......
Yeah I'l be passing on a corsa exhaust. Not worth the $$ for the minimal HP gain and chance of drone again.
On another note, I played around with the intake a bit, and I must say it made a tonn of dffeence. I removed the intak resonator, and the bottom plastic piece of the intake box as it was filthy as hell anyways. The car actually sounds like a V8 now. I might just leave the exhaust as it is, as I don't plan to race the car. I have other cars for that, but was mainly looking for a bit meaner sound when I got on it. I like hearing the RPMS as I drive. :highfive: