of course there's no way to say for sure without scanning , but with just a downpipe , i'd venture to say it's probably getting some KR. if you don't demod , i'd get the zzp powerlog asap.
http://shop.zzperformance.com/store/...Power-Log.aspx
i seriously doubt the level of modding you have is hurting the engine. all that's been done is the way it SHOULD have come from the factory. the stock exhaust design is very restrictive and chokes the engine in it's own exhaust. all the mods have done is allow the engine to breathe better. which is where the extra HP comes from.
if he put the modular pulley system on , you'll need a supercharger pulley puller to get the hub off and press the old pulley back on, otherwise you'll have to buy a modular 3.8 pulley.
most of these cars came from the factory with 4-6 degrees of knock because of the crappy exhaust setup. the Ubend behind the cat and the front manifold being 30% smaller than the rest of the system is the source of that knock. the 3 inch DP and the zzp plog corrects those flaws. you wouldn't be doing the car any favors by going back to stock. plus both my front and rear stock manifolds in my 2000 with 118,000 have both already cracked. it's a common problem. didn't even know the front was cracked till i took the heat shield off to replace it with the plog.
the only downside to your mods is the colder copper plugs need changed more often...15k miles or so. but at $2 a plug it's not a big deal other than having to actually change them.
