steps for installing duals

[RustyRodder]

so next week Im installing the duals on my 87. heres what I have:

-95 mustang headers
-95 H pipe
-thrush turbos
-OEM tailpipes


so Ive removed and capped the AIR tube from the header, as its not needed on the vic. the smog pump we are going to gut and cap off the head. added adaptors to the pipe and got OEM hangers for the tails.

the intermediate pipes are the only problem, as the pipe i bought for it fits the mufflers fine, but not the H pipe- just going to weld the pipe right to the H and not worry about it

so what else has to be done? the H pipe has two bar things midway back, pointing towards the center. do these have to be removed? and will some universal exhaust hangers be fine to replace the stock style ones on the mufflers?

are there any other things i should know?

[RustyRodder]

ok, so Ive been searching.

Lincolnmania said (in 2007 :p) :
"2.5" midpipes: flowtech intermediate pipes for a 86-93 mustang with approx 12" od 2.5"" extension"

do these work? because i would much rather be able to clamp and bolt it together then deal with welding.

[1987cp]

Those do work, and there's plenty of room to clamp or weld extra tubing behind them. I should have a set of Dynomax midpipes I can send you if you want to go that route, though you'll need to obtain flanges separately. However, my preference is the Maremont 339221, a 2.5" midpipe for an S-10. It's kink-bent and you'll need to slot out the holes in the flange (which is included), but it tucks the mufflers up a bit more nicely. Though, I'll note that even those needed a little extra tubing added when I installed them with a short-case muffler (Dynomax 17734). Go with a longer muffler and you should only need muffler clamps and a hacksaw, with no need for extra piecing.

[RustyRodder]

Those do work, and there's plenty of room to clamp or weld extra tubing behind them. I should have a set of Dynomax midpipes I can send you if you want to go that route, though you'll need to obtain flanges separately. However, my preference is the Maremont 339221, a 2.5" midpipe for an S-10. It's kink-bent and you'll need to slot out the holes in the flange (which is included), but it tucks the mufflers up a bit more nicely. Though, I'll note that even those needed a little extra tubing added when I installed them with a short-case muffler (Dynomax 17734). Go with a longer muffler and you should only need muffler clamps and a hacksaw, with no need for extra piecing.

is there a difference in the dynomax pipes?

I have a 2.5" H pipe, and 2.5" inlet dia on the mufflers. the mufflers have an 19" total length.



Im looking at this because I would rather have a clamp system over welds, for easier repairs if needed.

[88Vic]

If you clamp/bolt it together, check after about 500 miles if the bolts are still tight. My Vic had a new stock replacement exhaust put on it before I go it and after about 500 miles I saw that the bolts had worked there way out a bit, thankfully not falling out so I retightened them and put a bit of exhaust sealer over the bolts to hold them in place. I don't know why they did that, the system vibrated as much as any stock car.

I'm sure someone will tell me I don't know shit but this is what happend on my Panther so it's possible it could happen to you.

[RustyRodder]

thanks for the advice!

[1987cp]

is there a difference in the dynomax pipes?

I have a 2.5" H pipe, and 2.5" inlet dia on the mufflers. the mufflers have an 19" total length.

Nope, as far as I know all aftermarket 2.5" Mustang midpipes are completely interchangeable.

I should clarify that I didn't actually fit the Maremont S-10 pipes with a stock-size muffler (19" case, 24-25" overall), but it *looked* like extensions would not be required with the larger muffler case. This is one reason for my personal prejudice in favor of 19" muffler cases.

You know what, though ... I just remembered that when I added material to the ends of the Maremont 339221 midpipes when using the referenced mufflers with an 18.5" overall length, I had previously trimmed them shorter to fit the same mufflers in a clamped configuration with a different set of tailpipes. You could always try obtaining and test-fitting a Maremont 339221 midpipe on the side needing the longer midpipe and see for yourself. Worst case, you may end up returning it to the parts store, but best case, you'll be able to build your clamp-together system with minimal headaches.

Actually, if I wanted to get fancy, I could just look this stuff up and make a couple of measurements .... Let's see, based on the specifications at Maremont.com, these pipes were 31.25" long as delivered. When I get a chance I'll go out and estimate the effective length as installed with my old mufflers, and then we'll have a better idea of how they really fit with a short muffler.

[Lincolnmania]

cut the hangers off the mustang h pipe......you dont need hangers there

[1987cp]

Tape measure = good

Okay, I went out and measured the actual welded muffler and midpipe assemblies that I had under my vehicle for several months. The 31 inch mark was about 3 inches past the end of the muffler body on one muffler, and maybe 6 or 7 inches in on the other one. I was actually able to do one better, as the bits I originally trimmed off were handy on a shelf, and I was able to verify the tape measure's predictions using those. So, I predict that the Maremont pipes I suggested may actually work well with the short-case mufflers you've purchased. The one caveat I would mention is that these pipes do have a slight bend near the end, which crushes the pipe slightly, so depending on the exact length you find handy, you may need to use an exhaust pipe expander to smooth it out a bit if you find you need to cut on top of a bend.

[351m]

1 thing to add if you are doing a clamp together system... Spend the extra cash on stainless band clamps instead of the standard ones, they don't crush the pipe so in the event you actually have to pull it apart, it will be easier.