no cat?

[pimpdaddy]

i was planing on just cuting out the cat on my 91 legacy. I was just wondering if this would set off some sensors, and also what size tubing should i use to fill the gap?

[know1]

don't do it

if you get a cheap hi-flo cat you will gain just as much hp as if you went catless and it's nicer on the environment

[Legacy777]

In all actuality, gutting cats is probably worse then leaving them in. You get a lot of turbulance in the open cavity.

Is this on a n/a or turbo car?

[pimpdaddy]

Yeah i drive a 91 legacy awd with the 2.2 non turbo motor.

[Imprezive]

forget it, there is no point. you wont even notice any gain in power and all you are doing is polluting more.

[know1]

I actually read an article in turbo magazine that showed only a 1hp gain using a test pipe over a hi flow cat.

[206er]

well thats really relative. on something like a high hp turbo or NA motor a cat or muffler of any kind will kill some power. for a stock NA legacy I bet about 1hp would be accurate.
Ive done the cat gutting on a stock NA exhaust and its not worth the effort unless your cat is broken up/clogged in which case definitely do it.

[Imprezive]

1hp is only important if you are in a regulated racing class. Like Spec Miata

[91RHDLEGACY]

I have a few legacys, and I cleaned out the cat on my rhd, it had no noticeable affect whatsoever, the o2 censor is pre cat, so there was no cel. just make sure you have absolutely no exhaust leaks pre o2 sensor, it will decrease performance quite noticeably.
all you need is a pry bar, a hammer, and a bit of time to clean the cat out, make sure you get the wire netting and other metal out too.