Drilling hole into Catalytic converter

[Swarley]

This will sound very stupid but i just need to know. A guy i know who has been a mechanic for years tells me that if i drill a hole straight through my entire catalytic converter it will give me a slight horsepower boost, and give better sound. i will take all and any opinions here as to what could happen to my precious car if i were to do that because i just dont know.

[dmnowaksr]

If he is telling you to do this to your 2001 SSEI,I would advise against it. A hi flow aftermarket cat would be a nice upgrade though. Gutting a cat on a OBD2 car will more than likely give you at least an intermittent CEL. OBD1 cars are no problem though, since they don't have an O2 sensor after the cat. Do a 3" downpipe and a hi flow cat along with a fender well intake and you will be surprised at the difference in your performance. These are also nice supporting mods for others in the future also.

[Swarley]

ok. what would you recommend as far as a downpipe and hi flow cat? and i put in a bigger air intake would an FWI replace that?

[haro1225]

http://shop.zzperformance.com/store/p/3 ... npipe.aspx

[Swarley]

ok that will work. ill get a cat later. would an intense fwi replace my air intake?

and would i need a tune after just a downpipe?

[mylittleblackbird]

Need a tune? No. Benefit from one? Yes.

Yes, the FWI replaces your factory ducting and air box. It places the filter in the fender rather than the engine bay.

Please, keep the cat.

[Swarley]

Ok. Thanks alot everyone. Big help as usual

[nos4blood70]

Do the tune after your down pipe, PLOG if you choose to do it, and the intake. That way the tune will get dialed in for all the mods you've done.