With my 22re rebuild I am constructing a new exhaust system. Got a LC header on the way and will be finishing the system off with a flowmaster delta 50 series muffler. However, I am a little confused as to what "high flow" cat should go in (need one for emissions). I looked on summit racing and there are over a dozen that show up for a 2 1/4" application ranging in length from 12" to 16" and price from $50 to $100. What is the difference between 'um?

 

http://store.summitracing.com/defaul...=egnsearch.asp

 

ahy high flow cat is fine... be careful though ,if your truck is obd2, as some cats are not obd2 compatible

 

I think most trucks, if not all of them with 22re's are not obd2. You should be ok. Check out ebay, there is a guy that sells catco cats for really cheap, from what ive heard they are a really good cat.

 

Cool. Thank you for the replies. Will length of the cat effect the exhaust system? Does it change performace or sound?

 

the cat might change the sound a bit, but probably not enough to be noticed... any high flow cat will suffice, i wonder if going bigger would be better though, more catalyst to clean stuff out.....

 

Catco Cats have been known to have the bricks inside of them fall out. From what I've heard. I have a Random Tech one in my car and it seems to work fine. I'm pretty sure that an 87 22RE wouldn't have and OBDII system. They more or less came into effect in cars in the mid 90's. So you don't have to worry about having a bung cut in or anything.

 

Having a longer cat than neccesary would probably hurt your performance. Cats slow the flow of exhaust so they can clean out some of the particles in your exhaust. I would say a 14"-16" cat is all you need.

 

a high flow cat will be fine... remember you cant have 0 backpressure.... the truck still needs a little bit to run properly....

i just recently put my muffler back on, and immediately noticed a jump in having more low end torque....