All things exhaust

lumberjackV6 said:

i want to start a thread that consolidates everyones exhaust issues comaparing different pipes and headers and all that good stuff. I personally have a few questions to start with. 1) how important are headers in the power and sound of a car? 2) how much of a pain in the a$$ would if be to get dual exhaust now and headers later? 3) are catbacks inherintly better sounding (more throaty and growly) then axle backs? 4) are catbacks also more expensive, harder to find and a pain to install? talk amongst yourselves. feedback is greatly appreciated
T

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Unfortunatley you have come into the forum when participation is at an ebb, so I will contribute what I can.

How important are exhaust headers to the power and sound of a car?

Since “sound” relative to exhaust systems is very complex and the end result is based on individual perception and mechanical elements, I’ll not address this aspect suffice to say, YES, headers create a much different sound than manifold exhaust systems. Manufacturers employ entire teams of individuals and scientists to do nothing but develop amplifications and sounds relative to exhaust systems. This could become a novel. hahhahahahaa

I’ll hit on your power question and since I do not know how much of a mechanical background you have I will outline the fundamentals.

Exhaust headers assist in increasing power by reducing back pressure. Simple mechanical engineering: in a four-stroke engine, the engine produces all of its power under the power or compression stroke The other three strokes are unfortunate necessary evils required to make the power stroke possible. If these three strokes consume power, they are a drain on the engine.

During the exhaust stroke, a good way for an engine to lose power is through back pressure. The exhaust valve opens at the beginning of the exhaust stroke, and then the piston pushes the exhaust gases out of the cylinder. If there is any amount of resistance that the piston has to push against to force the exhaust gases out, power is wasted.

Once the exhaust gases exit the cylinder they end up in the exhaust manifold. From the manifold, the exhaust gases flow into one pipe toward the catalytic converter and the muffler.

It turns out that the manifold can be a tyrannical dictator of power since exhaust gases from one cylinder build up pressure in the manifold that then affects the next cylinder that uses the manifold and this increases exponentially until exit.

The idea behind an exhaust header is to eliminate the manifold's back pressure. Instead of a common manifold that all of the cylinders share, each cylinder gets its own happy little pipe. After their wayward travel through the pipe they dump into the collector.

In equal length header design, the individual pipes are cut and bent so that each one is the same length as the others. By making them the same length, each cylinder's exhaust gases arrive in the collector spaced out equally so there is limited back pressure generated by the cylinders sharing the collector. Unequal header design spaces out the exhaust at longer uneven intervals and to many are preferential in total reduction of back pressure.

So how much power are we talking? Meh…. For a well designed, correctly installed header system, from a reputable manufacturer, utilizing high-end materials, with no other changes anywhere from 15-25 HP/TQ. Of course, the end increase depends on the diameter of the pipes, mandrel design, length of the pipes, etc. The variables are as vast as opinions concerning which is best.

lumberjackV6 said:

how much of a pain in the a$$ would if be to get dual exhaust now and headers later?

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If you are going for a true dual exhaust on the 4.0L, it is highly recommend that you design the entire system at the same time. Pain in the arse or not, the entire system will be a better design if you modify it as a cohesive system. Pay now or pay later it is a personal decision that only you can make.

I will allow someone else an opportunity to reply to your other questions.

lumberjackV6 said:

i want to start a thread that consolidates everyones exhaust issues comaparing different pipes and headers and all that good stuff. I personally have a few questions to start with. 1) how important are headers in the power and sound of a car? 2) how much of a pain in the a$$ would if be to get dual exhaust now and headers later? 3) are catbacks inherintly better sounding (more throaty and growly) then axle backs? 4) are catbacks also more expensive, harder to find and a pain to install? talk amongst yourselves. feedback is greatly appreciated
T

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1. headers play an important part of the sound and the power. they free up the exhaust flow, which adds power. with the increased flow, comes more power. size of headers also changes the power/sound. a larger primary tube will increase the upper RPM power, but hurt low RPM torque. like wise, a smaller primary tube will increase the low end torque, but limit the power potential in the upper RPMs.

2. if you have the muffler shop do all the fab work, then you only have to open your wallet. it can be done either way. if the muffler shop knows ahead of time that you will add headers later, then it can help them create a dual exhaust system that can be adapted to headers very easily. if you fail to let them know/decide after the initial install headers will be a little harder to install. the big key here is to plan and communicate with your exhaust shop your intentions.

3. i dont know for 100% if the V6 uses 2.5" mandrel bent exhaust tubing like the GT. if they do, then a catback syste, will not add anything but $$ over an axleback system.

4. catbacks are harder to install, simply because there are more parts and you have to route the intermediate pipe over the axle, which is a little tricky. they are usually more expensive, due to the additional piping and parts needed for that kit.

does this help you out any?

Welcome back Jenn05. That info help me decide what exhaust system I'll go with for mine when I get it done. Good explainations. You too BigCat.

Yes, welcome back indeed!

Ok, a few more thoughts, do you plan to go FI later down the road? If you do, here is how I would go about doing it:

Super Charger

• Long Tube Headers
• Better flowing X pipe would be my choice for SC

Turbo

• Headers are optional from my research, the only option is the PH turbo, and LT's don't work with it, though ST's do
• On the PH kit, they provide a Y for duals, you won't need or benefit from H or X

Just some tidbits so you plan around your FI goals. I personally like the sound of the H pipe on our cars.

Thanks Rygen. It looks like you have done REAL well with the 4.0L Stang.

I am impressed and very happy to see that you did your research, developed a solid modification plan and executed it with awesome results! SCHAWING! (I will refrain from any leghumping at this point.) lol

Well done my friend!!!!!

4.0 Exhaust Response

I bought a 2007 Pony Package in June. The ONLY thing I hated was the single exhaust. Duals for me was a must. I began reading threads and talking to alot of great guys in the fourms, including Rygen from 4.0Collective (really good site for just us sixers) I saved alot of time, money and frustration. I think I wound up with a pretty good set-up for the 4.0 S197's. I ordered the Magnaflow Cat-Back system but for a Mustang GT with the regular style baffled mufflers...not the V-6 dual set-up which comes with tube type Magnapacks which are IMO overly harsh sounding and have a painful amount of highway drone. I also had an X pipe installed as I may get a blower down the road. I did lose some low end torque at lower RPM's..no doubt. But I noticed stronger pulling ability when I downshift to third while passing at highway speeds and when taking off..if I get the revs up...she launches better than ever as you'll see if you click the link below. The task of deciding on which exhaust was daunting with all the choices...hope this helps.
http://www.youtube.com/watch?v=NlUwi4Ew-lQ

greaser said:

including Rygen

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he is a member here as well.

greaser said:

I noticed stronger pulling ability when I downshift to third while passing at highway speeds and when taking off..if I get the revs up...she launches better than ever.

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and I've noticed the same thing ... with good acceleration response at hwy speeds - - - even in Overdrive!

Most of my driving is at speeds above 50+ MPH (a long commute) and the ecomomy, handling and braking on these cars is very much appreciated ...

I just love this car ~

DRIVE FORD!

bigcat said:

he is a member here as well.

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Indeed, this was one of the first forums I started on.

How much are we talking dollar-wise for duals installed by a good shop??

stanmckinney said:

How much are we talking dollar-wise for duals installed by a good shop??

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It varies depending on where you live, cost of labor, etc. But most are able to do it for $500 or less. It's more of a sound or looks preference than a performance gain on our 4.0L's NA.


NA, the single produces the same results really. On FI, it has not been proven that duals have a significant gain over singles. Only speculation at this point.

I had a CAT back dual system put on mine. $75.00 gt take offs,about $200.00 for left side mid-pipe and hangers,about $190.00 gt bumper cover and $210.00 instal with H pipe fabrication. Still have the JBA shorties to install.

i have a magnaflow duals. thye came with the magna packs. it sounds ok, but its not as good as i thought. they been on a few months. like i said there ok. i drove down to florida i really noticed how bad the drone is on that trip.

does anyone day the jba duals. i want to maybe get a differant dual set up. i also want an x pipe and hi flow cats. any suggestions?

mrjimmy said:

I had a CAT back dual system put on mine. $75.00 gt take offs,about $200.00 for left side mid-pipe and hangers,about $190.00 gt bumper cover and $210.00 instal with H pipe fabrication. Still have the JBA shorties to install.

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Mr. Jimmy,

This is what I'm thinking about doing. I have the GT takeoff muffs, I have one installed now and it sounds really good. Did you get the midpipe from the muffler shop or did you buy a GT takeoff pipe and have them mod and install it??

Has anyone out there tried this with a Y pipe instead of H or X, and what kind of results... I am probably not going to do headers, at least not in any forseeable future.

Thanks,

I was under the car when the shop did my duels.

The V6 has 2.25in pipes comming off the exhaust manifolds, they come together at a 2.5in collecter, from the collecter back, its 2.5in just like the GT.

The GT has 2.5in pipes all the way from the exhaust manifolds to the tailpipes.

This actually works to our advantage:

The rear of our y-pipe has the same hangers as the rear of the GTs x-pipe.

I bought my GT h-pipe from a guy who had replaced his with a x-pipe. He cut the h-pipe after the cats so it didnt screw with emissions.

I cut my y-pipe so the piece that I removed was about 1in shorter than the h-pipe I had to go in its place. I slipped the h-pipe over the cut y-pipe and hung it in the factory hangers. The shop welded it up and I had a oem looking 2.5in h-pipe. From there back its all GT exhaust.

At some future point I want better looking tips but I like the sound and performance of the Gt exhaust.

LIZARDKING,

Glad to hear your input. You had the exact same plan as me. I bought a set of GT take off exaust from a local owner (flow tubes and mufflers) and just got my FRPP x-pipe in the mail today. Your install is exactly what I'm planning.

GT Take Offs / dont forget the hangers

Guys I've been running my GT take-off set for about 15 months and I strongly suggest that you bite the bullet and purchase a set of Ford muffler hangers for the driver's side.

Its been just one hassle after another with the set of "homemade" hangers that my installer fab'd for mine!

shooterm1 said:

Guys I've been running my GT take-off set for about 15 months and I strongly suggest that you bite the bullet and purchase a set of Ford muffler hangers for the driver's side.

Its been just one hassle after another with the set of "homemade" hangers that my installer fab'd for mine!

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Thats the only part I'm lacking is a set of OEM exhaust hangers and I've got a set on order at the local ford dealer.

shooterm1 said:

Guys I've been running my GT take-off set for about 15 months and I strongly suggest that you bite the bullet and purchase a set of Ford muffler hangers for the driver's side.

Its been just one hassle after another with the set of "homemade" hangers that my installer fab'd for mine!

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you still looking for those? i can try again if you still need them.