My daily driver is a 1992 GMC Yukon GT 5.7L TBI and when ever i get it on the frreeway at speeds 80mph and above and then get off the freeway. As I sit on the off ramp I get a real strong smell of sulfer. this also accurs when i push it to those speeds in the early morning when n one else is around me. I believe it is running fat but i am not sure if i can adjust anything or if that is just how it runs. Curious if anyone may know. Thanks.

 

Sounds like the catylitic convertor. Just a guess, I remember one going bad on a friends car, it smelled too. Dont know how to test it though. Pressure test ??? I dont know.

 

sounds like you need a mopar for a dd.

 

that could be but i just had a high flow cat installed.

 

Isn't that the truth! I can surely tell you the next vehicle i get will be a MOPAR! Unless i can get my doba fixed then that solves everything

 

tap on the cat and see if it rattles. I installed one on my j10 and had it last me about 6 hours. (thank you dead cylinder)

 

I will have to try that cause i know at idle it has been misfireing like crazy. I think it is time for a tune up.

 

Uh-huh -yeah ....yessiree bob, 10-4, im withya'...

 

Most of us up here in the great white north view the catalytic converter as an obstruction to flow, conversely reducing some horse power, it is our view that things that reduce horsepower are to be removed at once and never replaced.

 

I did that just ran the exhaust from the y-pipes. but my beautiful little county i live in has emission test and they don't like vehicle that do not have cats. Trust me way better acceleration and definitely can feel the power difference.

 

shitty deal, I hate rules myself..lol

 

Yah. If i could own property outside of the county i live in and then register my truck to there i wouldn't have to worry.

 

as long as you have cats during the inspection...

 

Atta boy John, you know whats up bro...

 

haha

 

True very true but when i did that the wife felt it was a little to expensive to be doing that every too years. Unless i could figure out how to make it where i can just bolt it in.

 

What you can do as long as you can pass emissions inspection without them is to separate one in half, hollow it out and bolt it over top of the exhaust.

 

if they find a gutted cat, they will flip their biscuit... big fines for that

 

Yah i know but i wonder if i could just weld connecting plates or something on each end and bolt them together or something like that.

 

thats what a buddy of mine did, a flange on both end of the cat and a piece of straight pipe the same legnth with flanges. 4 bolts and it was ready for the rollers. if i remember right he had to weld a bung in the straight pipe for the oxygen sensor

 

All they got here is a mirror on a stick, so if it looks good from 6 feet away then it should be fine. But I pulled mine long ago, and use private inspection stations that really don't care about mods. Also someone was telling me about combination cat muffler and all you had to do was produce the paperwork for it and they let you go, not sure if this works but that's what I heard.