True dual exhuast V6 = lose HP & TQ ?

TJ · 11-09-2005, 02:30 PM

This is for the guys thinking about going true dual exhaust, I see a couple guys saying you get x amount of HP increase if you go dual exhaust and then I have read guys say the V6 you will lose HP because unlike the V8 the 6 needs back pressure. I have read this several threads not just the one linked and one guy say not even talking about back pressure said his car was diff slower with the true duals.

I do not know which is true I am new to V6's I would research it before you go true duals if you do not want to lose any HP or TQ.

Seems if this back pressure loss HP & TQ is true it might be wise to go with the Y pipe when going duals and even better not so free flowing mufflers for the duals.

Not trying to start flame just letting you know do the research & make your own decision

Quote:

"The comments about backpressure causing losses in torque and HP on the bottom end are coming from owners of older V6 Mustangs that have dynoed before and after exhaust changes and reported the results. Stock V6 motors have reacted poorly to true duals "
http://www.mustangforums.com/m_57313...ressure/tm.htm

StupidTodd · 11-09-2005, 04:07 PM

I have true duals (not JBA true duals, REAL true duals with no X or H connecting them)

And, I'll be the first to admit that I lost a little power by adding them... Not much, but it does feel a tad more sluggish... Actually, I don't think I 'lost' power, I think it just moved higher up the RPM band.

I'm working on the 'long term plan' and not really interested in the short term gains I could see.
I plan on adding a charger (most likely a turbo setup of some kind, still refining that plan), with a turbo, you get all the back pressure you could ever want

TJ · 11-09-2005, 04:26 PM

Quote:

StupidTodd

I have true duals (not JBA true duals, REAL true duals with no X or H connecting them)

And, I'll be the first to admit that I lost a little power by adding them... Not much, but it does feel a tad more sluggish... Actually, I don't think I 'lost' power, I think it just moved higher up the RPM band.

I'm working on the 'long term plan' and not really interested in the short term gains I could see.
I plan on adding a charger (most likely a turbo setup of some kind, still refining that plan), with a turbo, you get all the back pressure you could ever want

Thanks for (honest opinion) posting I am deciding how to set up my exhaust I don't have a lot HP/TQ as it is now and IMO I don't want to lose any more of either. I am thinking of going with a Y pipe another stock V6 muffler little (little fab muff) for left side. I am thinking this should diff keep the BP. You know I have a stick and going through the gears not even hard maybe shifting at 4K you hear the engine rumble up and single exhaust is little loud its a healthy sound not loud but healthy. So with duals it look nice not as loud as after market of course but will have a little louder sound vs single.

I have been also reading up on this V6 I have no plans for any of this right now, but if I ever decide to go power adder the way this engine is designed internally from what I read IMO it would be turbo only not supercharger you are right on.

Sancho805 · 11-09-2005, 04:49 PM

i have the JBA true dual exhuast kit and i have not noticed any loss in power compared to when it was stock. i have not ran it on a dyno but if there was any loss, it was not big enough to even notice. if anything, i've felt a slight increase in pep when i take off at green lights. i would love to see dyno results on a h-pipe true dual so that i can know what my car is pushing. the sluggish feel that StupidTodd is feeling could be a loss in TQ, not horsepower. i'm sure it runs like the wind when jamming on the highway.

TJ · 11-09-2005, 05:15 PM

Quote:

Sancho805
i would love to see dyno results

I have to agree 110% with ya on that , the seat of the pants isn't accurate its an opinion, but for someone to admit after installing dual exhuast thet their car feels slower is pretty honest.

I like to see some 100% proof one way or the other but I have a feeling the BP is needed on the V6, and I do not want to lose through the low RPM range and pick some up when I on the car and then at 4000 or above (i pick some up) when I shift at 5200.

rygenstormlocke · 11-09-2005, 05:19 PM

If back pressure is a real issue, then yes going to a Y or H pipe should be just fine. A tune will also help along with a CAI if you are going true duals. Most people go with X, H or Y pipe. These all should be fine on near and long term horse power gains. Going true duals from the cats would be for signifiant power adders, and I would also replace the headers at this time.

You should be fine with a prefab kit.

05redfireV6 · 11-09-2005, 05:26 PM

Trust me, going with a true dual exhaust will not cause a loss in either horsepower or torque. As long as it is done with some thought. All our engines are is big air pumps power is created by moving air in and getting air out, and if you get rid of the air coming out (e.g. less restrictive exhaust) it should serve to create a vacum effect to pull more through the car. This process is the same with any engine regardless of the fact that if is a 6 or an 8. When you talk about losing power, you might be refering to the loss of low end torque. (www.3.8mustang.com) has a good article about exhaust size. It says that anything over 2.5in as far as duel exhaust is too much, because you will loose some low end torque (seat of your pants feel.) However, if you have more Air coming in (e.g. supercharger, turbo, NOS) theoretically you should need to have more air coming out. How do you think those ricers get away with those HUGE exhaust system, because their engines have to rev to make power. And they have half the displacement that we do. For example Honda S2000 (2.0L 247hp and 153 ft/lbs of torque) Can you see the difference? Unless you build a high end screamer, which for us would require redoing the internals, you don't need a huge exhaust system. I personally have the manual and I have a custom dual exhaust (h-pipe) with flowmasters and headers (2.5in exhaust, 1 5/8 in headers). I have the Mustang GT 17's, and I still find it hard to find traction when I take off. Of course a LSD might help. It is actually really loud and drowns out the radio when I have the windows up. I will tell you though. A true duel exhaust (no x or h pipe is not good for your car.) Your engine will actually start to run like two different engines over time. One bank may run lean. Also I am sure it creates a lot more vibration as there is balancing out of the exhaust pulses. If you are running True duels , no h or x-pipe. I would really consider getting one.

TJ · 11-09-2005, 05:26 PM

Quote:

If back pressure is a real issue, then yes going to a Y or H pipe should be just fine

Like you said IF the BP is an issue

Wouldn't the Y pipe be better than the H pipe Y=more BP ----H pipe = less BP <------more like true dual exhuast less BP.

I am not doing any other mods I want to install a dual exhuast but I do not want to lose any HP or TQ in my low RPM range, in the future no plans now maybe slight maybe if a decent turbo comes out in year or two and its cost (cheap) effective

TJ · 11-09-2005, 05:47 PM

Rygen you have your car setup nice is that a stick/w 4.10's or auto. Nice car!

StupidTodd · 11-09-2005, 05:53 PM

Quote:

ORIGINAL: TJ
Thanks for (honest opinion) posting ....

No problem, I was fully aware that I would lose a little backpressure when I made this change, and that I would end up losing power because of it. I viewed this as a necessary evil that I must endure until I can get to where I want to be.

Quote:

ORIGINAL: Sancho805
the sluggish feel that StupidTodd is feeling could be a loss in TQ, not horsepower. i'm sure it runs like the wind when jamming on the highway.

You are absolutely correct.

Quote:

ORIGINAL: TJ
I have to agree 110% with ya on that , the pants isn't accurate its an opinion, but for someone to admit after installing dual exhuast thet their car feels slower is pretty honest.

I like to see some 100% proof one way or the other but I have a feeling the BP is needed on the V6, and I do not want to lose through the low RPM range and pick some up when I on the car and then at 4000 or above (i pick some up) when I shift at 5200.

Sorry, didn't get the car on the dyno before and after. Running on a dyno generally costs money, and I have plenty of other mods that I could better spend said money on.

I would say I lost power between 1800-2750, but gained slightly at 4000+.

I agree pants isn't accurate, but it's all I gots to base my opinions off of.