will running no catalytic converter in a 4.9 cause any problems,was told it will run rich plus other problems, anybody running no cat that can provide some info

Probably some relevant posts in This thread.

I don't think the 4.9 has a downstream o2 sensor, (correct me if wrong) and running a cat delete pipe, or just simply straight piping through the cat shouldn't cause any running problems. It will SMELL different... like an old 66 mustang, but other than that, there's no real adverse effects. You may want to check your state and local laws though. In ADA county here in Idaho if you don't have all the original emissions control systems in place that the car came with, it won't pass (in this case EGR, and CAT). Hope this helps,

-Mitch

------------------
My Car - 87' GT 3800sc
//www.fiero.nl/forum/F.../HTML/121571.html#p0