what is the main area of restriction on a 2002 WS6 exhaust...someone told me its the muffler followed by the manifolds..i thought the 02 iron manifolds flowed very well? the cats and y pipe look the worst to me i think i am going to cut off my muffler and have no tips? should i do it

 

The WS6 exhaust is fairly free-flowing as it is. I would say the most restrictive parts are the 'flat' part of the y-pipe, the muffler, and the cats. But like I said, even all of those parts are free-flowing from the factory.

I dont think you should cutout the muffler. I would advise you to get a catback exhaust system such as GMMG, Corsa, Magnaflow, etc. I dont think it would look very good w/o any exhaust tips.

 

with the cutouts in the TA or WS6 rear bumper, i agree...no tips would look strange.

i'm currently running no tips on my Z but it doesn't have any cutouts for them.

i would think the muffler is the worst part of the system. not by much.

the flattened sections of pipe on the Ypipe actually have similar cross sectional area as the round pipe. and yes the later year manifolds flow decent...for manifolds.

just go ***** to the wall...LTs, ORP, true duals

 

I second that! No y-pipe setup can compare to how good a true dual setup does

 

Actually, the stock exhaust does extremely well. This includes the "Y" pipe. The only parts that might even remotely be called restrictive are as WS6store mentioned, in that order.

Cutting out the cats is illegal, and offer virturally zilch improvement since todays cats are essentially restriction free (unlike the old bead versions of the 70s & 80s). The "Y" pipe design alone is very low restriction. Replacing them with a dual setup isn't going to result in any notable performance gain.

A cat-back system that eliminates the "squashed" section just before the "Y" pipe and perhaps a freer flowing muffler is your best bet.

But again, don't expect to notice a difference in your times.

IMO, there's plenty other areas to spend your money where it will do more good first.

 

The stock "flattened" Y-pipe is not restrictive at all...If you don't believe me, replace it with an SLP Y-pipe and do a dyno to see if there is any difference...

As for the flow rate of a stock SS/WS6 muffler, it's definitely a little better than what comes standard on the Z28's, Formulas, & T/A's. So, just replacing your muffler with one like a Magnaflow, Hooker, or Random Tech won't net you much of a gain or any at all on a stockish car. If you want to gain a little over what you already have, get a full 3" cat-back system (as the stock I-pipe is 2.75"). I picked up a dyno proven 26rwhp with ONLY a lid & cat-back system over bone stock on my 2002 Z28. Now, I guarantee ya at least half of that gain alone came from the aftermarket cat-back I put on!

Regarding the stock manifolds, cats, & Y-pipe, I gained a dyno proven 16rwhp with longtubes + a highflow catted Y on the same bolt-on car...

As you can see, everything is still restrictive enough to gain something on a stock-internal car. Obviously, these exhaust mods will show even better gains once you do a cam and/or heads/cam in the future (same with Forced Induction).

Mike

 

Kyles 2000z ur right..I just choped off the muffler and its looks funny with no tips but it sounds SO GOOD...stock 2002 exhaust and no muffler sounds GREAT..cant decide if i want to go ahead and fab up a y pipe/3.5"tips at a exhaust shop with the stock 2.75" catback or go and get the 3" SS loudmouth.. i think im going loudmouth bc its stainless and i think the 3.5" slash cut tips will look sweet. its 350$ though which sucks. It sounds GOOD but looks retarded right now w no tips. think ill gain anything from going to a 3" pipe(loudmouth) from the stock 2.75"? for 350$?