Replacement Exhaust

[Mhoop]

I have a 72 with a 302 automatic. I need to replace the entire exhaust system, which I believe to be the original exhaust. A friend recommended pypes.com for a bolt on kit. He has an older camaro and said everything fit perfectly. Any thoughts on this for a Mustang? Anyone used them? Any alternate company that you recommend? Any info is appreciated. Thanks for reading.

 

[MustangSally44]

Doesnt matter how nicely it bolts up if it doesnt sound right. We have duels with headders and it sounds tinny. Our next exhaust will be much more rumbly

 

[71ProjectJunk]

Please be aware that if you have the "competition suspension" with the staggered rear shocks, I don't believe that anyone makes an off the shelf exhaust system that will fit, you will have to have a local muffler shop make one for you. You do not want to order an exhaust system and pay the shipping, to then find out that it does not fit. The shipping charges going both ways will kill you. Check your rear shock to make sure that they are not staggered before you order.

 

[detritusmaximus]

Two things that can make the exhaust sound weak or tinny are stainless steel mufflers (they tend to use thinner material because it's stainless) and small mufflers. Bigger mufflers tend to sound deeper.
There's also a difference between perforated core and chambered mufflers. They have different acoustic dynamics and can affect performance differently.
Unfortunately, I have no idea which is best for the old Mustangs. My biggest goal, back in the day, was to avoid the 3k rpm drone.

 

[Stanglover]

I installed Flowmaster FX 2 1/4" with custom made tail pipes (staggered shocks)
The drone is much less than the old Flowmaster 40's I took off. The FX are certainly worth considering imo. I posted a video on the sound of these, so it's likely somewhere in the files on here.

 

[Hemikiller]

Precision Exhaust offers a factory style single and a retrofit dual exhaust for use with manifolds. They're carried by most Mustang vendors.

https://www.precisionexhaust.com/
NPD has the retrofit H-pipe and dual exhaust kit.

https://www.npdlink.com/search/products?search_terms=5246-11B&top_parent=200001&year=1972
https://www.npdlink.com/product/exh...5210-28&top_parent=200001&year=1972&year=1972

 

[RIBS]

Precision Exhaust offers a factory style single and a retrofit dual exhaust for use with manifolds. They're carried by most Mustang vendors.

https://www.precisionexhaust.com/
NPD has the retrofit H-pipe and dual exhaust kit.

https://www.npdlink.com/search/products?search_terms=5246-11B&top_parent=200001&year=1972
https://www.npdlink.com/product/exh...5210-28&top_parent=200001&year=1972&year=1972

I bought the NPD kit and it was tough to mount to the manifolds, but I finally got it by bending the H pipe with ratchet straps. Otherwise it’s great. It’s not a Precision Exhaust kit, I called them to discuss fitment and they said it wasn’t their kit….the NPD a kit was fairly complete, I think I just had to add some hangers and clamps, added the H pipe to complete it…

 

[mrgmhale]

We have an X-Pipe on our 73 Mach 1 exhaust system (Hooker long tube ceramic coated headers and Flowmaster mufflers). The X-Pipe will in theory give you more power, but in practical terms you may not be able to tell on the street. What it did, however, is mellow out a lot of the harshness that comes from having headers (they do not absorb sound as well as cast metal manifolds), and it lowered the operating temperature of our engine street/strip built 351 by 2 degrees.

For our 73 Mustang Convertible with a stock 302 2v and a dual exhaust system using the oem manifolds, the prior owner used an H-Pipe with the dual exhaust system he had installed (it was a single exhaust system originally). The tone from its exhaust is deep and throaty, with no tinny or droning sound at all.

As for which is better, X-Pipe or H-Pipe, there is a video from Engine Masters that broaches that subject. From what I can discern the X-Pipe will take out more raspiness, but either one is better than not having one or the other.

 

[timachone]

We have an X-Pipe on our 73 Mach 1 exhaust system (Hooker long tube ceramic coated headers and Flowmaster mufflers). The X-Pipe will in theory give you more power, but in practical terms you may not be able to tell on the street. What it did, however, is mellow out a lot of the harshness that comes from having headers (they do not absorb sound as well as cast metal manifolds), and it lowered the operating temperature of our engine street/strip built 351 by 2 degrees.

For our 73 Mustang Convertible with a stock 302 2v and a dual exhaust system using the oem manifolds, the prior owner used an H-Pipe with the dual exhaust system he had installed (it was a single exhaust system originally). The tone from its exhaust is deep and throaty, with no tinny or droning sound at all.

As for which is better, X-Pipe or H-Pipe, there is a video from Engine Masters that broaches that subject. From what I can discern the X-Pipe will take out more raspiness, but either one is better than not having one or the other.

What I have learned about the endless discussion, H-/X-pipe or nothing, is that without a dyno you won't feel any difference power-wise. Sound-wise there are differences: straight is the loudest and most muscle one, H a bit tamed and more evenly, X the most quite and different sounding version. Power-wise H should make some plus in the lower range, X in the upper range. But the advantages are only minor concerning power. What I have read through was also that you can mess up when you do not install the H or X in the absolute right spot. Then it could be that you are worse power-wise than without them.
Therefore I came up with the solution of 2,5 inch straight pipes for me with Hooker headers and Flowmaster mufflers. Using headers and their absolut different routing how could I just say where the sweet spot is now in comparison to an OEM exhaust? I like that sound of my exhaust system without a cross connection. With a 4 speed and a 3.50 gear ratio I doubt I would feel any difference. Especially as I build my whole engine and even more, restored the whole car.

 

[Mister 4x4]

I have a Pypes 2.5" stainless system with X-pipe and Street Pro mufflers - came as a kit, backing up a set of Hooker ceramic-coated Competition headers. Since my engine was seized when I got the car, I have nothing to compare it to, but I like it fine. The engine's a 351C-2V w/Edelbrock 4bbl Performer intake & 1406 carb, CompCams mid-range cam, roller everything, and some mild port & polish.

I'll have to post up a quick video and pics of the underside later. I can't seem to locate my previously uploaded gallery pics, and my work computer's not havin' it (as far as file sharing goes).

 

[73' mach 1]

I did FPA headers, pypes 3" x pipe from the headers to the street pro mufflers which is 2.5". Never finished the exhaust yet. Not sure if I'm just going to add turn downs, run the exits in front of the rear tires or go over the axles. Undecided...

 

[droptop73]

Since you're asking for opinion... LOL!!
Keep your manifolds, unless you are trying to extract every little bit of power headers are not worth the hassle (arguments can begin here...LOL). A good replacement dual exhaust system and a nice set of turbo style mufflers will give good sound control and a "muscle" sound. I like the sound of both the Magnaflow turbos and the inexpensive Thrush mufflers I'm running now. 2-1/4" exhaust is plenty big for a 302, maybe too big for a mild build. Like mentioned above if you have the staggered shocks the tailpipes could be an issue.

 

[goodnigh]

Bought my exhaust system from Don of OMS, have comp suspension package
and it was a perfect fit. Don is a site vendor.

 

[giantpune]

Doesnt matter how nicely it bolts up if it doesnt sound right. We have duels with headders and it sounds tinny. Our next exhaust will be much more rumbly

My car is a basically stock bottom end and valve train 351 with headers and some cheap non-name-brand mufflers. The local muffler shop put it in for like $200 installed from the back of the headers to the tailpipes out the back.. Its been 15 years since they were put on, so I may be wrong. I think the paperwork said they were "turbo" mufflers like @droptop73 mentioned. Everything just happened to jelly just right. The car sounds great. Its got a rumble that lets you know its a V8 but not so loud it gets annoying.

My buddy had some fancy set of black widows or neighbor haters or some cutesy name. They were too loud and even he didn't like them.