Taking off second Cats. for delete bypass.
 

Hi,own a 03 boxster and iam getting those fab.speed secondary delete. pipes. I had the car up on jacks and was looking at secondary cats and the way they are bolted on and setup. It looks easy enough to take out on my own,but i notice the connection from the first cats. to the pipe to the second cats. the 3 bolts that connect it to secondary cats.The top bolt seems to have a nicely weld spot on the nut.As to me looks to make sure it doesnt come lose.This normal?I havnet tried losing it jsut want to know if that is factory done. If it isnt any reason y that top bolt would be welded? Thanks.

Sometimes nuts or bolts are tack welded for convenience, aiding in maintenance in case accessibility is a problem. I'm sure the OEM did it.

I think on your year there are 2 studs and 1 nut and bolt.

I replaced my secondary cats with the Fabspeed pipes not long ago. My car is an '02 S; there were two bolts and one stud tack welded at the top. All came free with no major effort, though you must loosen the undertray to pull the cat pipes free. The sound is wonderful with my sport muffler.

With your sport muffler did it reduce the droning or make it worse or...? I have the Deluboz muffler and was planning on a rear cat bypass but the 2000-3000RPM droning is so bad right now I sure don't want it worse.

I have no droning at all. My sport muffler is a "Pedro" type modified where the bypass pipes are welded from the inlets to the tips. The sound is wonderful without the nasty side effects of the aftermarket mufflers.

I'll have to study the Pedro design again. Maybe an equalizer pipe between mufflers, that is a common fix in such a design as mine...