{EXHAUST} mustang manifolds

[gadget73]

OK, so I got the engine in and went to re-hang my exhaust on the Townie. Problem is, I cant get the flange to line up with the studs on the 88 HO headers. It seems like the bolt spacing is slightly off or something. I didn't try the exhaust on the driver's side, just the passenger's side. My air tubes for the cats disintegrated when I dropped it to weld the nuts on for my O2 sensors too. It also looks like they wont clear the header on the driver's side because of the position of the flange. On the old manifolds the top bolt is approx 10:30 and on the HO headers it sits like 12:30 or therabouts. I'm thinking I'll take all the parts I have to the local exhaust place and get them to mod it as needed to fit. I dont want to buy new cats so I'll see if they can re-use my old ones and just tweak it some.
Oh well, time to go finish up and run the hot rod Lincoln home with open headers. Would have been done last night but the power went out last night and I had to weave my way out of the shop in pitch dark. Not an easy task.

[Grand Marquis GT]

The HO headers DO NOT bolt up to the stock exhaust.

You will either need to get a mustang or mk7 H-pipe, or get your exhaust downtubes modified...

Heres a pic of the difference...

[85crownHPP]

yeah.... this is common knowledge!! you shoulda asked first before you did this

[gadget73]

yeah yeah. whats the fun of asking before finding out it doesn't work. I'm planning to haul it to an exhaust shop and get the stock H pipe modded to fit.

[Lincolnmania]

you could use a pair of 90 towncar headers............pete can you post a pic?
scott

[p71towny]

Do the towncar headers flow the same as mustang shorties? I swear I need to buy a 90 5.0 towncar and swap 95-97 cosmetics on it. Thatd be the shit.

[marquisman]

what about putting them on a 351W?

[beep_beep]

so how hard is it to switch out the manifolds to the stang headers? are the bolts hard to get to? thanks

[Archangel]

All the bolts on the are manifolds are easily accessible, worst is passanger side rear but it's doable. Stang stock headers I think were quite the same way, dunno 'bout equal length ones. Manifold/header-to-downpipe bolts are a little harder to get to, but a ratchet with a 10" extension will be your friend.

[gadget73]

Well, the headers don't perfectly mate to the stock downpipes. Having hacked mine to sort-of work, I'll say I don't highly reccomend it, but it is possible. If you do, be aware you'll need to drill a hole in the downpipes and have a bung welded in (nothing like a fresh bunghole) for the oxygen sensor. Check the positioning of the sensor before punching holes, or you'll end up like me with an O2 sensor jammed into the frame an an exhaust leak. You will also need to cut the ends out of the flanges so instead of an O they have a U and use a washer. Its not pretty, its not terribly professional, but it does work. Mustang H pipe and better exhaust is a much better solution.

[beep_beep]

Mustang H pipe and better exhaust is a much better solution.

i already have the mustang exhaust .... shhhhhhh lol

[gadget73]

Well in that case...
You'll need new bolts. Half the ones from the manifolds are too long. Might as well just get a whole set of header bolts unless you have the ones that came off the donor car. Load them up with anti-seize compound before installing them too and you'll be ok. Getting the nuts off the manifold will be a bitch most likely but if you have a hotwrench, or a small cutoff wheel (an air powered 4" jobbie, not a dremel) you can get it apart if it gives you any shit. If you don't have those, soak it really good in penetrating oil and hope for the best. They might come off, or they might snap. I do highly suggest a 6 point socket for this.