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bought it to replace my cracked stock y pipe(i dont want headers till ig et the 400 in the car) looks really good, welds are nicely done. but the fitment is another story, put on my car, the flange on the drivers side sits at a slight different angel so it pulled that part of the pipe down when tighten up. also the passenger side was bout 4" too short and at a completely different angel so i had to weld in a peice of pipe with a bend on it. deffently not worth the money in my opinon.
Mine was a perfect fit and still looks great after a few years installed. I'm very happy with it. Sorry to hear about yours though.
Laid side-by-side, the MAC and my stock pipe were a perfectly-shaped match. Your fitment almost sounds like it might've been their header Y-pipe. They look so much alike that, if they were sitting far enough apart from each other, someone might mistakenly grab the wrong one, not realizing they're different.
Did you contact MAC about it? Might be a little late now, though, but might be worth a shot.
i didnt directly order thru them i order it thru hawks third gen. i had even called to make sure. but its in and actually looks like it belongs there(thank god for auto body guys)
Hello, I have a similar issue with my 1988 305 tbi firebird. The Y-pipe does not fit my stock manifolds. Do I need any spacers? How did you solved your problem with Mac Y-pipe? Thank you!
OK just to clarify IIRC THE L69 manifolds and the 350 TPI manifolds are the ones you want. I swapped everything over on my Crossfire and also used a Magnaflow Y pipe which is the same fit as the L69 y pipe. I believe the Mac is spec'd for an L69 car as well. You still need the EFE spacer as well. On the TPI Cars it was just a spacer with no flap inside. So to answer your question - yes you do need to swap manifolds. Look for someone who swapped to headers on here and they might still have their old manifolds around. It took me a good month of searching to find a set.
OK just to clarify IIRC THE L69 manifolds and the 350 TPI manifolds are the ones you want. I swapped everything over on my Crossfire and also used a Magnaflow Y pipe which is the same fit as the L69 y pipe. I believe the Mac is spec'd for an L69 car as well. You still need the EFE spacer as well. On the TPI Cars it was just a spacer with no flap inside. So to answer your question - yes you do need to swap manifolds. Look for someone who swapped to headers on here and they might still have their old manifolds around. It took me a good month of searching to find a set.
Regarding EFE valve, I don't know, I have to ask to my mechanic.
I hope I can keep my manifolds, I need something like the photo attached, 2" in and 3" out in diameter, hope I can find it on the makret
I used to use those in place of that damn heat riser valve,bought a bunch at a swap meet for a couple of bucks,I think they were for a early 70's pickup.
The EFE (heat riser) valve isn't a huge deal....I just used an extension and busted the valve out of it and sealed up the holes with a couple screws where the valve shaft went through, so it was wide open and not restricting anything....
OK just to clarify IIRC THE L69 manifolds and the 350 TPI manifolds are the ones you want. I swapped everything over on my Crossfire and also used a Magnaflow Y pipe which is the same fit as the L69 y pipe. I believe the Mac is spec'd for an L69 car as well. You still need the EFE spacer as well. On the TPI Cars it was just a spacer with no flap inside. So to answer your question - yes you do need to swap manifolds. Look for someone who swapped to headers on here and they might still have their old manifolds around. It took me a good month of searching to find a set.
