Cat question

2fast4u_rx7 · 07-11-07, 03:57 PM

I have a 93 5 speed RX7 twin turbo and I had recently put on a down pipe. What a difference in power. I was told not to put on a mid pipe becuase of the boost creep. How do we know if the OEM Cat is still functional? I had a 2000 prelude with a high flow converter installed. One day I found some type of honey comb looking thing coming out of my muffler. I took it to a muffler shop and the cat had blew out. That was odd for a 3 year old cat. The cat in my RX7 is oem. Do these cats over blow out? How do we know we have boost creep. Also wondering If I purchase a aftermarket exhaust with a silencer will that help on restrictions? Thanks

rynberg · 07-11-07, 04:00 PM

1. Get a boost gauge.

2. Repeat, get a boost gauge.

The cat normally doesn't fail unless the pre-cat fails and takes it out. If you actually read about boost creep, you would know if you had it....

Running a silencer on an aftermarket exhaust is pointless. It will flow less than the stock exhaust.

Repeat, get a boost gauge.

danny hahn · 07-11-07, 05:49 PM

Simple test for your cat, if your idle is right, and your air pump works, stand behind your car for a few seconds, if you find your self choking or getting queezy, good chance your cat is bad.

I saw an obvious improvement with a good cat.

I take it you dont have emissions testing in regina?

Sgtblue · 07-11-07, 08:53 PM

DP is one of two of the most important mods. Add some header wrap or have it heatcoated to lessen underhood heat. The second/other mod, as rynberg indicated, is a boost gauge. Good advice on avoiding the midpipe.
If you have a good 10-8-10 boost pattern and your eyes aren't watering while standing behind the car, the cat is OK.