I sent an email to MAC about fitment issues that I have had with their headers. I think they are decent for the money but I have had a lot of trouble with the fitment. I have read on here that many others are dissatisfied with the fitment also. The response I got back was not what I was hoping for:

"we are not aware of any fitment problems with that system. as a matter of fact, i can not remember ever getting a call on the 96-97 LT1 systems. on most headers it is common that after removing headers, that the holes may not line up correctly. this is caused by the high tempetures at the port. the simple fix is to inlarge all holes on the header, so that you can move it back and forth and get the bolts in."

Anyone care to comment?

 

I bought my Hookers used (three years old, but FRESHLY recoated).. When installing my headers, I had troubles with one bolt on each header being too close to the primary. Slotting the holes a little more might have helped.

What I did was to clearance a cheap 3/8 12-point closed end wrench and it worked like a charm.

Just ground the outside ring of the wrench thinner and it fit. Since my header bolts don't have to be torqued too tight, the thinner wall on the wrench didn't hurt me too bad.

 

I bought a car with a set of those headers and I pulled them off and put them on my other car.. I ended up needing to slot the holes with an electric drill (a drill press would have been nice but didn't have one at the time) and I got them to fit with a little creativity. That's probably all you need to do. I really liked them when I got them on because of the easy plug changes.

 

They are on the car and have been for 2 years. I took them off recently to do some work and had to take the dremel to 3 holes to get them to line back up. Don't you think that is a little ridiculous? I wonder to myself why they would not put a flange in b/w the primaries so they would stay in place.

 

It's an aftermarket part. That's the way things go most of the time. I think I've just learned to deal with it most of the time unfortunately. If it's an easy fix just fix it and be done. I bought a brand new set of SLP headers for my GTP and they bang against the firewall when I put the car in reverse!!

 

Oh godd, thats gotta be ****ty. Ive learned to just live with the time as well.