Heres the link for the how-to for the TonyA mod:
http://www.cadillacfaq.com/faq/answe...ram/index.html
I'm thinking about doing it on my car, right now I'm waiting for odysseus to do a dyno comparison (stock vs volant vs TonyA I think) to see what the numbers look like. He says theres definately a "seat of the pants" difference going from stock to either the Volant or the TonyA but didnt know about between the two. He'd done the TonyA mod on his own 03 and said it definately helped cut down on low-end lag and resulted in a better overall engine sound. He's using the Volant now b/c the TonyA doesnt work with the V bumper. Currently I'm a little hesitant on cutting holes in my airbox or plunking down the $200+ for a good intake but we'll see.
On another note, you mentioned that there werent any aftermarket kits for the 3.2, I beg to differ.
According to K&N's websit
e, the FIPK #57-3040 (averages around $200 online) fits the 03 CTS (3.2L)
http://www.knfilters.com/search/prod...x?Prod=57-3040
Many car parts sites also list the K&N Air Charger Kit #63-1082 (runs somewhere around $250 online) as fitting the 03 CTS but I don't think it's "street legal" in all states and is not listed at the K&N site.
http://www.car-stuff.com/performance...9&part_name=15
I was planning on buying one of the K&N kits a little while back but couldnt figure out what the heck the difference is between them. If anyone knows, feel free to speak up.
According to the FRAM website, part #CA9459 (usually $31, on sale for $18 at Advance Autoparts right now) will replace the stock filter. This is a different number from what's listed in the TonyA how-to guide. I'm guessing its a new part maybe? If it does work as a replacement filter, that would sure beat having to mutilate your existing one.
http://cpgcatalog.honeywell.com/cpg/...LLAC&model=CTS
At the Volant website, part number 15632C is listed as a compatable intake kit (averages around $250 online).
http://www.volantperformance.com/pdetail.asp?ID=145
I should note that the K&N kits replace the ENTIRE intake system up to the motor while the Volant kit is only the airbox/filter and retains the rest of the stock intake (this is according to what other people in these forums have said and what I've seen at the websites).
Most people around here seem to go with the Volant if they've got the dough, or the TonyA if they don't. Best of luck to you and keep your eye on the "Great Air Intake Challenge" thread (in the CTS forum) for when odysseus posts his results from the dyno runs.