socalmk1

I have a 99 z28 m6, And I just moved back to California. Home of the smog *****. I have been reading the exhaust threads, but everyone usually goes for LT's. The only thing done to my car is a K&N FIPK. I plan to do a ported throttle body, LS6 intake and some kind of CA legal exhaust.

As of right now, I like the sound and quiet-ness of the stock exhaust. If I were to get some CARB-Legal LT's and catted Y but keep the stock catback, would it still be quiet? I could always do some electric cutouts when Im at the track.

Also, If I kept the stock exhaust and only installed cutouts, would there be any performance gain or are the stock headers too restrictive?

3rdCoastPowerSports

iTrader: (5)

I was under the impression that LT were an immediate fail at a "professional smog station". I think moving the cats from there original position is the main reason for the LT smog disqualification. I could be wrong but pretty sure. maybe try finding a "friendly smog guy" that way you can do what ever you like. (disclaimer: by friendly i mean a smiling certified state inspection station that follows and obeys all state laws. I advise you to follow all Smog laws here in California,,,)

TransAmWS.6

Chances are if you had a catted-Y and kept the stock muffler, it would still be relatively quiet, maybe just a bit louder but not much. Also, you will get probably 5-10rwhp with the electric cutout on the stock catback

dutinsss

iTrader: (2)

if long tubes are legal in cali(i have no idea), i'd get long tubes with a cut-out after each header and then stock exhaust after that. that way you have completely unrestricted exhaust when you want it, but still stock exhaust for legality purposes.

2win_SS

iTrader: (1)

No LTs are legal here in cali. Just shorties.

00'TwistedLS1

If I were u if just get a 2002 exhaust manifold if Cali is as bad as you say, there's a lot more stuff u can do than a cut out for cheaper and less money like a decent tune

2win_SS

iTrader: (1)

Run whatever u want a get a dirty smog. Easy

socalmk1

Easy, until you get sent to the referee.

socalmk1

Also, a dirty smog will run you about $250-$300 on an obd2 car.