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mustangrfast88
06-29-2007, 12:41 AM
damn mac header took me almost 3 hours to change one side header gasket i will never by a set inless they go to a one peice flange those multi flanges suck i love the mac h pipes and there cat back systems but the headers suck ok enough of me ranting i got it done and car is running alot better

Paul408Notch
06-29-2007, 12:55 AM
Does your keyboard not have punctuation built into it or what? :HYF:

I've found on my MACs, that if I start with the back bolt, and move my way forward, they line up a lot better. If you try to put the end 2 bolts in first, they won't line up for crap.

mustangrfast88
06-29-2007, 12:57 AM
it is broken, yeah i finally got it from starting at the front and working my way back. next headers will be a one piece flange.

JonS
06-29-2007, 06:59 AM
I used to have a set of equal length macs. I hated them, they would burn up a set of plug wires in nothing flat and it sucked reinstalling them. If you can get a bolt or two in the front or back you can pry them into position.

02mingryGT
06-29-2007, 07:39 AM
My brother has them on his 90. He was having problems getting them on and asked what I thought. I looked at them for a second, asked him if he had any money to be new ones and he said no. So I handed him a pry bar and said have fun.

He just burned up a couple of plug wires. Wait until I tell him it's probably because of his shitty headers.

Jeff88coupe
06-29-2007, 08:05 AM
All it takes is a few wire ties to keep the plug wires from laying against the headers...not the headers fault. A big pry bar makes lining the bolt holes back up alot easier. Some guys have bolted them up to a head on a workbench..then welded a piece of steel rod across the top/bottom of the flanges to keep them lined up. But...the old saying you get what you pay for applies to MAC stuff usually.

JonS
06-29-2007, 08:14 AM
All it takes is a few wire ties to keep the plug wires from laying against the headers...not the headers fault

That was not the case with my equal lengths. They were bent in such a way to achieve being equal length that they would actually burn the boot no matter what you did. I would get about six months out of a set of wires. That is one item that I would never own again. As for the prying, it's not really a big deal.

RACEME
06-29-2007, 10:25 AM
I actually bent my Mac's back into shape on the workbench before reinstalling them. I used an old head as a guide and banged on the flanges individually with a hammer and brass drift until the holes lined up perfectly. They went back on with no alignment issues.

venomous_svt
06-29-2007, 10:34 AM
I have heard alot of bad things about mac headers, especially on 4.6 SN95's. There is a big post over on svtperfomance about the welding slag breaking loose and getting sucked into the EGR valve, causing an engine failure. Thats f'ed up.

85_SS_302_Coupe
06-29-2007, 10:41 AM
They are a pain but i will say experience has a lot to do with how easy it is. I've done a few header swaps and i can manage without too much trouble, but when i did my head swap recently i couldn't get the headers on for shit...my buddy had each side on within 5 minutes.

Carl
06-29-2007, 11:29 AM
I like my Mac headers...didn't have any problems bolting mine up...I guess I got lucky.

mustangrfast88
06-29-2007, 11:50 AM
were your headers new or used if new i dont think there would be a problem but wait tell you got to take them off

Greg Seibert
06-30-2007, 11:57 AM
You guys should have wrangled headers on old 'Stangs and Fairlanes and Torinos (don't even bring up the starter bolts). Still have scars almost forty years later.
I've used asbestos tubing(like you see on EGR tubes) to eliminate burnt wires and boots.
Another thing to help installing I've done is ream out the holes in the flanges and trial fit them to a scrap head on the bench first. Pauls right, you will find a combination of which bolts to start first that works the best.

NXcoupe
07-05-2007, 02:24 PM
I have heard a lot of complaining about MAC headers, but I like them and don't have alignment issues, I start at the rear and use a pointed prybar to align one hole while I put the bolt in the other. I have had BBK solid flanges warp in a twisted fashion, but those still went on using the same technique.