Dropping stock h-pipe from 92 auto....collector bolt size? Tips?

BlownStangGT said:

Ok, Im gonna install my UPR off road X pipe...What I wanna know is what is the correct size for the header collector nuts? I dont wanna strip anything or break a studd coming off the headers....also...As I crawled under the car before, I noticed on the driver side, it seemed to be a little close for the one header nut to the cat, any tricks, or just try to work my way in there? Thanks...I really dont wanna snap a header studd doing this

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I assume you still have stock headers. I believe they have the same thread as BBK, Mac and most other headers.

Its been almost 10 years since i have even seen stock headers so i'm not gonna promise you this is right.

I am almost positive the thread is 12mm-1.75.

If/when you get new headers, i recommend installing stainless studs on your new header collector. They will in fact make your life alot easier down the road.

Driver side header collector:

I use several extensions (3/8) and a swivel to get to the stud nuts. You will have to go in at a VERY steep angle to get to them. Since they are stock, i would recommend spraying them down with something befor you start. Something like WD40 or similar. I also use a 3/8 impact too. If that H-pipe hasnt been off, i would definetely NOT use an impact.

Don't worry you will figure a way to get to them. Be advised, you may have to THROW something first befor you find a way.


At my house, when i am underneath the car, things tend to "grow wings" and start flying.

Good luck man.......

You'll have a little more room if you remove the o2 sensors first...

if it's stock don't use an o/r pipe at all. i don't care what anyone says, it kills low end torque a bit without the backpressure that cats provide. I RAN A BBK PIPE W/ CATS, WORKS BETTER. BUT COSTS A LIL MORE.