Alright...Putting MACs on my '95 t/a. Picked them up used off ebay. I started with the passenger side. Got stuck, they wouldn't go on. I couldn't get all six bolts on at once...always four. I put the back ones on, then the middle, and the front wouldn't line up. I put the front ones on, then the middle, and the back wouldn't line up.

So I took a break and did the driver side...CAKE.

Now I'm back, and they still won't line up. I have the bolts loose so there is still some play. Should these headers go right in? I mean I do have the back four in. Right now I'm prying them off with a screwdriver so I can see the bolt hole, and I ran out of time while I was watching/fiddling with the bolt trying to go in. Anyone else have a problem like this? Is it possible that they changed a bit of shape since they were used and that's why they don't fit perfect?

 

Try just putting in the front and back bolt, and working it from there. That's how I had to do the ones on my LX.

Get them on LOOSE and see if you can get the middle ones on. If not, get one of them little "mirrors on a stick" or whatever you need to see the bolt holes, and see if you need to maybe elongate the bolt holes with a dremel.

Good Luck!

 

Sometimes the Mac headers loose shape because they don't have a solid flange all the way across. You got to just bolt them on one at a time and try to pry them into place as your doing. It is just akward in the engine bay, I had the same problem with a set of Mac headers, but fortunate for me I got them on with the engine out of the car. Also, be very careful starting the treads when prying them into place because the heads strip very easy.

 

To get them to line up easily, work on the front and back, and then work towards the middle. Dont torque them down until they are all in.

 

take the header off and lay a exhaust gasket on the header flange and see if all the bolt holes line up. Mine didn't line up on my slp's i think cause i droped on but i just put it over my vice and cranked out so it spread the ports until the bolt holes lined up.

 

i had EXACT same problem, it was a complete PITA!~


just keep prying it and be carefull not to break off a bolt, good luck and dont get discouraged

i had the same problem

 

Ahhh yes MAC's, individual header tubes. That's why I bought BBK's, 1 piece flange

 

Well the exhaust gasket lines up pretty much fine, and the bolt ALMOST lines up in the front, just a shade off too short. I'll keep trying....

 

I just got mine back on, had to fight with them for over 2 hours/ in a 2 day period. What a PITA!!!! My advice would be to get the back and front bolts in (keep them loose) and go from there. Good luck.

 

I installed macs on my 97 Z28. I was under my car for a couple hours with this problem. I gave up and had my two buddies finish for me. They both did it at the same time, one guy sitting on the engine and one guy under the car both pushing and pulling as hard as they could. They ended up getting it. Try this technique as it might be a two man job.

 

think it's OK if i widen up the holes on the end a little bit with a file/dremel and make them oblong?

 

If you do that, the port on the head may not line up like it should with the primary tube for that cylinder.

 

Cripes, now I'm worried!

I was planning on taking my headers off to get them re-ceramic coated. Is it a sure bet that due to the heat cycles that the headers have warped some and would cause the bolt holes to not line up?

 

MAC headers are a PITA. Took me and my buddy nearly 2 1/2 weekends to get those things on. The passenger side was misaligned and I had to send it off to a machine shop to have it bent back into shape.

I will never buy MAC again!!!!

Good luck with your install. Once you get them on though you will be excited b/c the SOTP difference is pretty noticeable. Make sure you use some good metal gaskets and I don't recommend felpros with MACs b/c you will probably get a leak.

 

Ahhh, warpage! That's one thing I like about my Macs. I know they aren't going to warp and leak.

-Chris