From what I have been finding, the best mods for a 3.2 TL are to upgrade the headers, get a CAI, and upgrade the crank pulley. I don't know if this is a given, but if I were to get new headers, will I get a performance gain without changing any other part of the exhaust, or do I need a cat back to really notice gains from the headers? I plan on purchasing an Injen CAI soon, but didn't know if I should go the header route. I really don't want to take away from the class of the car which was why I was hoping to keep the oem exhaust except the headers. Also how would the noise change if the headers were only replaced?

If I were to go with a cat back it would be Apexi. I think it sounds great.

 

You don't need to replace the stock exhaust to get noticeable gains from headers. You'll get about 20WHP from headers alone in higher RPMs - only FI can give you more. In regards to catback exhaust systems - only the ATLP exhaust gives more than the typical 5 or so WHP that Apexi, Comptech and the others given (or so I've read here). I have headers without aftermarket exhaust and it sounds great!

 

headers will give u a noticable gain, u will feel a stronger pull in the higher rpms.
best bang for the buck: CAI (comptech ice box, injen, aem), headers (comptech, dc sports, xs), pulley (crank only- UR), exhaust (so many), tb and im spacers (p2r or outlaw engineering), weight reduction

 

Take it from someone who's done all those mods...is an original owner of a 2002 TLS & has over 135k miles...stop with Headers & UR pulley.

From personal experience...

#1 I would never spend $$$ on an aftermarket exhaust (unless it was paid for by insurance). The $$$/performance ratio is probably the worst of all possible mods. If money is burning a hole in your pocket then I'd suggest you do this mod LAST. If you want "looks" just get tips. The sound is great at first...but thats very subjective...especially when you get older. FYI...aftermarket exhausts make a bigger difference with a NON Type-S (since their exhaust diameter is .5 inches smaller).

#2 I've tried various intakes before...and if I had the chance to do it all over again, I'd get either the icebox or leave it stock with a K&N filter. As your car ages, maintenance plays a more of an important role than performance. Any intake where it takes additional work to get to the air filter only causes you to NOT check it as often. I know I sound like a broken record...but the sound is great at first...but thats very subjective...especially when you get older.

#3 Headers...depending which ones you get you MAY notice some noise...however not in the same way an intake/exhaust will make. At a certain RPM (~2-2.5k), the headers resonate depending on temperature/conditions. This type of noise definitely does NOT bring a smile to my face, however the performance increase more than makes up for it.

#4 UR pulleys. To be honest of all the aftermaket mods, I've come across...this probably has the least amount of complaints I've either read about or experienced. The perfect time to install this mod IMO is when you change out your timing belt.

#5 I know it wasn't discussed...but I figure I'll add to this anyway...DO NOT replace any of the exhaust resonators with a straight pipe. From personal experience, all that did was INCREASE the resonance noise from the headers.

 

i removed my resonator when i had dc sports headers. it gave it a more g3ish sound and had little to no resonance.

 

Pretty much covered it here. I would add that you can improve the header results by getting them ceramic coated. This will keep more of the hot exhaust gas in the pipes, which results in accelerating those gases out. When doing the intake, you can look at doing the big bore intake treatment. Meaning you can have the throttle bodies bored out, but to get the most from it you'll need to port match the intake and the hard rubber part that is between the 2. Note, the 1st gens only have one TB.

Ruf
02 WDP TLS, Black Interior with Black Grill Inserts
**1/4mile 14.46 @96.07MPH (45-70mph test - 3.5 secs)
(**before headers, Hi-flow CAT, IMMs & Bored & Match Intake System
17x7 Konig Appeals SMF with P225/45ZR-17 Kumho SPT
(used Ziex 512s track only)
CT Icebox, RamAir, Sways & Springs
3nd Gen Innovative Motor Mounts
BBTBs & More, Mugen Cooling Mods & Thermoblok
Ceramic Coated XS Headers & Random-Tech Hiflow CAT
NEO Anti Freeze & NEO 5w-20 oil
Tranny #3 Installed 11.17.2008