I had SLP headers installed and I don't feel any difference.
If any change, I would say the car feels weaker.
Shouldn't I feel a good gain? I didn't expect it to rip the
seat bolts out of the floor board, but my car might be slower.

I believe I have a small leak at the y-pipe flange.
Could this be a problem?
Maybe I'm getting false knock, from the leak and louder exhaust?
Somebody told me I needed to reset my PCM, is this true?
If so how?

Any suggestions?

 

Anybody???

 

You might wanna invest in an LT4 Knock Module as you can be getting false knock and definitely can rob you of power. As far as resetting your PCM just unhook your battery and let it sit for atleast 15 min and hook it back up and should be good to go.
I would double check to make sure all exhaust leaks are fixed.

 

Don't know about you being down on power, but sealing the driver's side collector on my 97 was a nightmare. If yours is leaking it's going to burn through the gasket quickly. In the end if you have a 1/4" ds collector flange, call SLP and order the 3/8 flange and have someone weld it on. I tried every trick in the book and nothing worked until I replaced it. They should be burned at the stake for selling headers with 1/4" flanges.

Good luck man, besides the hassle they have been, I think the SLP headers look good and perform fine.