to gut or not to gut

[Rev-it 84]

My 3.2 is stock except for a Dansk sport exhaust. I just passed my last emissions
test so now the modification begin. My goal is a SW chip, but before I do I need to mod the Exhaust. Question is, What is the difference between a gutted OEM cat
and a by-pass pipe in relationship to HP gain and overall performance. Thanks for your input.

[Zeke]

There isn't a lot of difference no matter what you do. 5 HP seems to be the consensus after many threads have been posted and discussed. There was one yesterday with a dyno graph and all.

[Rev-it 84]

I read the post and it is very informative, to me it seems that the one in one out system is the best bang for the buck. I guess 5hp gain with the Fab-speed by-pass is worth $285.00, looks good too. But then the saying goes"chrome don't
get ya home".

[aigel]

Why not backdate with SSI? Much of the restriction is in the headers, IMHO.

George

[aigel]

Why not backdate with SSI? Much of the restriction is in the headers, IMHO.

George

[Rev-it 84]

My original plan was SSI w/chip, but I want to retain my stock heater system with
blower. If someone would produce a stainless crossover pipe which would replace the OEM one that would be the best solution, but here in the south Atlanta area I cant find a quality welding shop to Fab one.

[Por_sha911]

What happens if they change the law (like they did in CA) and start testing your year again? FWIW, I say make sure you can change it back to smog legal if needed.

[gtc]

You could ditch the heater crossover pipe and backdate the heat as well. The B&B's I'm putting on my car let me keep the crossover, but I will be backdating the left side heater outlet.
There is a thread here somewhere that details a modification to the heater blower relay, whereby you can delete the engine compartment blower while retaining functionality of the footwell blowers.

[Rev-it 84]

I have a spare OEM cat with slightly melted ceramic witch would be my donor. Also the B&B crossover sounds good but I can't find any info, that would be a perfect solution for SSI and keeping the stock heater system without using the flexible heating duct over the fan shroud.

[porsche930dude]

I would advise against gutting it. You can buy a bypass pipe for a fraction of what you can sell your cat for. Heck you can probrobly pay for one for what theyre paying out for scrap converters. Plus you may want to reinstall it oneday. Open you will get a touch more flow and quite a bit more sound.

[Rev-it 84]

The old one is partially blocked, ceramic inside got pretty hot and melted so it wouldn't be of much use. Found that one chasing a drivability problem, ended up with a complete engine rebuild.

[oneblueyedog]

I've got a gutted cat.

I got my hands on a euro pre muff and run that.

If you search the forums, you'll find that you actually lose HP with a gutted cat.

HP nearly equals SSI setups with the Euro pre muff and Sport muffler. At least according to this forum.

[Rev-it 84]

After reading several threads, and the great advice you guys have given, it only makes sense to by-pass and install a SW chip. $285.00+gaskets vs $2000.00SSI> Thanks