L67toLS1

iTrader: (4)

What that said.

SHINER

iTrader: (18)

Some of the SS's I believe got Loudmouth's, etc.

Which are pretty raspy once you go with a ORY and longtubes.

I would go Magnaflow.

RPM WS6

iTrader: (3)

Stock SS and stock WS6 cars both received the same catback.

The only thing that separates the SS/WS6 catback from the rest (Z28/Formula/Trans Am) is the slight difference in muffler. The SS/WS6 cars get dual 2.5" outlets on the muffler and the others (Z28/Formula/Trans Am) get 2.25" outlets on the muffler.

So to answer your question, the only difference is the slight muffler variation/tailpipe outlet size. And of course the stock tips are different as well.

Of course '98 SS/WS6 cars had that entirely different catback that used a single (on the left side), large outlet muffer with single tip. But that was only in '98.

RPM WS6

iTrader: (3)

The only optional SLP catback for the SS cars during the LS1 era was the SLP dual/dual system under the Y2Y RPO. And the muffler used on that system was slightly different than the one offered in the aftermarket dual/dual catback from SLP.

Loudmouth was not offered as a factory/SLP option through GM.

L67toLS1

iTrader: (4)

Don't the SS cars have 3" piping going into the muffler?

TAtoad

iTrader: (22)

ok, so all 98 SS/WS6s have single pipe? i thought it was only some

RPM WS6

iTrader: (3)

SS/WS6 have the same I-pipe going into the muffler as the Z28/Formula/Trans Am. They are not a true 3" like the aftermarket systems are, more like 2.75" stock.

RPM WS6

iTrader: (3)

I remember reading somewhere a long time ago that towards the end of the '98 model run, the WS6s were already getting the dual outlet setups like the '99+ cars would eventually get. But I'm not sure if that applied to the SS cars as well.