My 91 Formula(TBI 5.0) has Edlebrock headers. It also has a low hanging cat by the driver side door. The muffler shop guy told me that I'd have to get stock exhaust manifolds back on it to keep the new converter where it should be, because the header pipes cause the funky downward angle of the pipe which goes into into the cat. Has anyone had this problem?

 

when i installed headers on my 89 formula i noticed the pipe on the pass side was low to.
I have had the setup on for about a year and no problems yet. I wouldnt worry about it.

 

The edelbrock's tend to do this. Go with Hooker's for $150 and get them coated (without AIR though)