Suggestions on re-doing my exhaust?

[TDR]

Getting my '66 Mustang, 200, on the road meant a few concessions in regard to cost vs what I eventually want to do with it. Sounds familiar, right? Anyway, I'm currently running the stock manifold, a stock (size and type) of muffler, and dual tailpipes.

This setup works ok, except that we must have used too large-bodied of a muffler, because the differential smacks into it something terrible when the suspension compresses.

So, looking ahead, I definitely want to install a header, plus re-do the exhaust system as well. Would you fellows care to offer up some suggestions to the following?

Single or dual-outlet header?
Single or dual pipes?
Pipe diameter?
What about that "X-Pipe" thing?
One or two mufflers?
Type of mufflers?
Location of mufflers?

I'm not trying to build a race car, but I certainly want to get as much performance as possible from this investment, plus end up with a nicely throaty (not raspy) exhaust note. I definitely want the tailpipes run out the back of the car, and don't like the idea of anything hanging down and showing underneath, either.

I actually ran a Midas Muffler Shop years (many, many years) ago, and we used to do a lot of custom exhausts. However, the only dual-exhaust for a six I ever remember doing was a totally hokey-folokey sidepipe setup we installed on an old Ford van. (Sure wish I would have taken some pictures back then)

Now, for dual exhaust installs on V-8 powered pony cars, it was not unusual for us to apply twin, super-mini "turbo" mufflers, mounted just ahead of the differential, either with or without the transverse "stock" muffler behind the diff.

We tended to stay away from installing glass packs, because they were just too loud for the street. They were small, and easy to tuck up under the cars for a neat installation, but were very loud.

What I call "turbo" mufflers were really just very small, conventional mufflers, whose application was in reality that of a "resonator", and were to be used in conjunction with a full-sized muffler on stock installs. Those turbos were very compact - barely taller than the diameter of the exhaust pipes themselves, but we still had a tough time getting them tucked up into the area that I mentioned, just ahead of the rear diff.

I would sure appreciate hearing from any of you guys who have successfully achieved a neat, performance-enhancing, good-sounding system. That's not asking too much, is it? Haha. Seriously, any info would be really helpful. Thanks!

 

[grocery getter]

Hello,
I like the dual out long tube headers. there are a couple of sound clips in the eye candy section of member's cars with headers.

the 2into1's with the 123 and 456 grouped together are best for our firing order.

from what i've read, most guys here also prefer the turbo mufflers. 8). I have the hooker header with an H-pipe(someday i'll hear it run) i'm not sure an H-pipe or crossover is needed with our little sixes. it might just sound better without it.

 

[bigcatchdaniel555]

Definetly go with duals if money will alow connected to dual out headers on the front. Most people recommend FSP, Pacemaker or Hooker headers for best fitment. I peronally have pacemakers from Mike and cant complain at all.
Search the archives for sound clips I post a couple of weeks ago the duals with just turbo mufflers that came with the v8 kit I modified from summit. However I would recomend a shop it wasnt worth my time. I had a single exhuast with flowmaster and the duals sound way better! The x pipe is debatable some people say it helps others say it was meant for v8's. the reason being is that v8's have turbulance in the exhaust because of their uneven firing pulse whereas the 6 has a perfect 180 degree pulse. The uneven pulse created heat in a certain part of the exhuast so a crossover was put in that spot to help reconcile the problem.

Have Fun...
Dan

 

[Gene Fiore]

Definately go with a dual collector header. It will sound much better. I have a Hooker super comp dual collector header with a 2 inch exhaust system with an h-pipe and dual Magnaflow turbo mufflers ran all the way out the back. If you search for posts from me on this site you will find pics of it.

 

[350kmileford]

Is 2.5" just way too big? If so, what kind of horsepower would justify 2.5"?

 

[bigcatchdaniel555]

I've heard of people with a single 2.5 inch exhaust but I dont think Ive seen any duals I have 2.25 duals if that counts for anything. I'm not an expert but I dont think a 200 needs a dual 2.5 system because it cant displace enough air in each cylinder to provide adequate backpressure in the system something like a 428cj can because its double the size and putting out much more air volume per cylinder.

 

[Gene Fiore]

Is 2.5" just way too big? If so, what kind of horsepower would justify 2.5"?

The collectors on my Hooker headers are 2.5, so IMHO a system using 2.5 pipe would be too big. 2 1/4 would be the biggest you would ever need. Just my 2 cents.

 

[LincolnMarkVII]

I was thinking for my own project, I'd run a single 2.5" to a Warlock muffler, and then run the muffled outlet tube to the right side of the car, and run the cutout tube (with one of those electric valves on it) out the left side of the car.. both behind the rear tires like it is now on one side.

Not to derail the thread too much, but with all these 6-2 headers around, has anyone tried making a 6-3-1?

 

[mysavioreigns]

Exhaust sizing

That's a good basic chart I found a while back. Don't know how reliable it is, but it seems to follow everyone's opinion.

 

[Harte3]

Vizard claims the "needs back pressure" thing is a myth and more than 5# of pressure in the system ahead of the muffler is not optimum. But I think contemporary flow theory has it that long, smaller diameter tubes are better for scavenging/suction than large, short tubes for low to mid range operation.

 

[rommaster2]

The backpressure thing is somewhat a myth, all depends on what your using the motor for. High RPM race motor backpressure=bad, but our sixes as i found out after cutting my muffler off, enjoy the backpressure because they're all low rpm operators.

However i have a 2 inch single pipe from the manifold and it serves its purpose, gave obvious increase over the stock, sounds better, and looks a bit better too (the stock was old, rusty, and sagging).

If i had cammed my motor, i would have bought a header too, but i don't see the point since i will never gain that much from a NA build with it as the internals are all stock.

 

[The Plankster Prankster]

well here's my advice on the group of questions in the first post:
if you choose a single-outlet header, use a single pipe all the way back. if you choose dual-outlet headers, run dual all the way back. one muffler per pipe is all you need unless you want it super-quiet

as for pipe diameter, there was a thread in the big-block side of things about that, and enlarging the pipe too far will reduce both teh backpressure and the velocity of the gases. an ideal condition has the pipe sizes such that the backpressure is minimized without losing too much velocity, as the velocity is helpful to suck the gases out of the cylinder. my 300 has a 2.5" pipe and thats plenty for it.
the point of what i just said is that you shouldn't jump blindly to a bigger pipe on the assumption that bigger is better

as for mufflers, my truck popped the turbo muffler the first time i ever heard it backfire. that's their weakness. i installed a cherry bomb glasspack, and its louder but not excessive. its quieter than the beater did with a big crack in hte manifold and a turbo muffler.

oh, and don't try (like i did once) to hold the system together with muffler-clamps, get it welded together everywhere except where the header meets teh pipe. my truck has one piece from where the pipe meets the manifold all the way to the tailpipe (ahead of the tire), and it sure beats how i had the beater with the muffler clamps!!!

well i hope something i just said was useful to you
--josh

 

[TDR]

I'd sure like to hear one of those sound bites, but I can't figure out how to find them.

 

[LincolnMarkVII]

Well the exhaust fell apart on my Fairmont this morning. It's completely off the car now behind the manifold. I ordered a Flowtech Purple Hornie slip-fit (NOT the header muffler) and we'll try to fab up a cheap but full (out past the rear axle) 2 1/4" exhaust to take its place. I'd offer to record that and post it, but I don't think I have anything capable of a good recording AND portable enough to not be a hassle.. maybe my laptop? We'll see.

 

[bigcatchdaniel555]

http://youtube.com/user/bigcatchdaniel555 This is a link to my exhaust pacemakers to dual out summit turbos pipes are 2.25

 

[TDR]

Hey BCD555, that setup you've got sounds really good. Are you running dual-outlet headers? Also, at what point under the car are you crossing under the trans/driveshaft to get the left-side pipe over to that side of the car?

 

[bigcatchdaniel555]

Its mike's dual out pacemakers with 2.25 pipe all the way back from a 289 system the one pipe crosses over about 10 inches after coming out of the header just using simple elbow pipes.

 

[Bort62]

If I wasn't turboed, I would use a dual outlet header, into a Y-collector and a single 3" strait out the back. The reason you want to maintain exhaust velocity is because of the venturi effect (http://en.wikipedia.org/wiki/Venturi_effect). As your high velocity pulse passes from one primary into the collector, it creates a very slightly lower pressure region in the other primaries, which in turn draws a little more exhaust out of their respective cylinders. This is the primary reason tuned headers make so much more power at high RPM, when the pulse velocity is high.

If the header is designed right, anyway. That's what is tuned about it, and why things like equal length are important. Once you are in the collector, you can't really go too big w/ the pipe. An infinitely large pipe is the same as running open headers. So maintain velocity in the header (don't go too big on primaries) but go w/ as little backpressure (restriction) in the exhaust post-collector. Backpressure is BAD, and is a function of volumetric flow rate, which in our case, is a function of RPM. That's why too small of a pipe or too restrictive of a muffler will really hurt you on top but feel fine on the bottom.

Run your choice of muffler. I have a glasspack on mine and it is not loud at all, but it is also muffled by the turbo.

You could also run parallel 2.25" pipes strait out the passenger side, but that would be a lot more difficult and expensive to do. It would look cool however. Very BMW-esque.

But why have the exhaust cross over the the driver side? V8 Envy?

 

[wallaka]

Because it looks cool. The only reason you need.

As for backpressure, I agree with the Prankster. No engine needs backpressure. None. People that experience a loss of power going to larger exhaust have compromised their exhaust velocity. Size the pipe according to the volume of air pumped, and you will do fine.

This takes (very little) maths, so looking up a chart would be the easy thing to do.

 

[TDR]

I may have my priorities mixed up, guys, but I'm placing equal importance on sound, looks, and performance. I guess the way I am approaching this is:

1. I want the car to sound good.
2. Have two tailpipes sticking out the back.
3. Get some performance boost over current setup.

Presently, I'm running stock manifold, and one pipe back to a full-size, transverse muffler, with two outlets. Tailpipes exit out the rear of the car, and it is very quiet.

From the very beginning, I realized that I wasn't going to end up with a very fast car. If I wanted to go that route, I wouldn't have kept the 6. However, there's a lot to be said for having a good under-hood appearance (header), good sound (turbos?), dual tailpipes (traditional hot rod look), and finally to get some decent performance from 200 cubes.

It sounds like you guys have some really good setups. I just didn't expect there to be such variance in which way to go (single pipe, duals, turbos, glasspacks, single or dual-outlet header, etc).