Single or Dual Exhaust... Which one for performance?
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From: Indiana
Single or Dual Exhaust... Which one for performance?
Hey,
I posted another thread asking who prefered mufflers over straightpipes. Now I would like to know which exhaust is better from a performance stand point. I want my truck to sound deep and throaty but i am willing to sacrafice some "loudness" to performance. Which would be better for my 99 For Ranger 4x4 (4.0 OHV). I am looking at the Flowmaster 40 series mufflers right now due to price. I cant spend a bunch of money. What should i go with, single or duals? And what pipe and tip size.
Thanks,
Chris
I posted another thread asking who prefered mufflers over straightpipes. Now I would like to know which exhaust is better from a performance stand point. I want my truck to sound deep and throaty but i am willing to sacrafice some "loudness" to performance. Which would be better for my 99 For Ranger 4x4 (4.0 OHV). I am looking at the Flowmaster 40 series mufflers right now due to price. I cant spend a bunch of money. What should i go with, single or duals? And what pipe and tip size.
Thanks,
Chris
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From: Danville, VA
flowmaster 40 series is a good choice...
word around the forums is that single exhaust is best for our engines....with too big of pipes or duals we loose some backpressure, which is NEEDED for our power, as we have relatively small/medium sized v6's...
a flow 40 with 2.5" cat back, 3" after muffler will be fine...great sound and performance...i have my exhaust dumped, and as i'm now wanting loudness over power (i already have enuf) i'm going to get a dual exhaust muffler and dump them...
word around the forums is that single exhaust is best for our engines....with too big of pipes or duals we loose some backpressure, which is NEEDED for our power, as we have relatively small/medium sized v6's...
a flow 40 with 2.5" cat back, 3" after muffler will be fine...great sound and performance...i have my exhaust dumped, and as i'm now wanting loudness over power (i already have enuf) i'm going to get a dual exhaust muffler and dump them...
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From: Fuquay Varina, NC
on a 4.0 OHV, i would run a smaller pipe, that engine has more torque. and it lacks a top end, using a larger pipe will not help the top end for that engine, but it will kill the torque. on my ohv i used one single 2 inch pipe, but you could go with a 2.25. you can use ANY size tip you want. if you run duals go 2 inch.
on the 4.0 SOHC i would run a 2.5 single or a 2.25 or 2 inch dual
hell on my 450hp 351 cleveland im running dual 2.5s, same on my 5.4. dont go overboard with the larger pipes
on the 4.0 SOHC i would run a 2.5 single or a 2.25 or 2 inch dual
hell on my 450hp 351 cleveland im running dual 2.5s, same on my 5.4. dont go overboard with the larger pipes
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From: Danville, VA
yah on the 3" part, i was referring to tips...as they are what makes the sound come out
so bob, on my 4.0 ohv, i need to run 2.25 from cat to muffler, then from muffler, dual turn downs...is that gonna work out ok?
so bob, on my 4.0 ohv, i need to run 2.25 from cat to muffler, then from muffler, dual turn downs...is that gonna work out ok?
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From: Fuquay Varina, NC
that should be ok, the turn downs is what concerns me, that a major loss in backpressure. would you consider a single turn down?? turn downs work very well for engines that have a higher RPM power band, and the OHV is not well known for that. keep the pipe size realistic and i think youll be just fine
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From: Fuquay Varina, NC
the 4.0 ohv doesnt make that much noise, the only time i got it to make a little noise was with a dumped glasspack, but it sounded like a ricer, so i got rid of that. eventually i put a turbo muffler on it with side swept before the tire, and damn if it wasnt as quiet as stock
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From: Indiana
Alright so if I go with a Flowmaster muffler, which one should i get if i want some rumble? I was thinking a single 2.25 pipe all the way up to the tip, then maybe 45 it and put a 2.5 or 3in stainless steel tip. If i was not to 45 it, I was thinking about putting a dual tip on it and have it exit where the stock one does. Is this alright, or will I loose back pressure and what not?
Thanks,
Chris
Thanks,
Chris
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From: Murfreesboro, TN
FWIW, I had a dual straight-piped setup originally on my truck.
2.25" main pipe, split into two 2" pipes the remainder of the way.
Sounded good, but like Bob said, I lost backpressure. Now, I've got a single 2.5" system, and I immediately noticed a return in extra bottom-end grunt. And it's pretty loud, too. You can't sneak up on anyone, lol.
2.25" main pipe, split into two 2" pipes the remainder of the way.
Sounded good, but like Bob said, I lost backpressure. Now, I've got a single 2.5" system, and I immediately noticed a return in extra bottom-end grunt. And it's pretty loud, too. You can't sneak up on anyone, lol.
Still El Presidente...
Joined: May 2004
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From: Texas
single in, dual out is my preference...
tomorrow, i will be welding true duals w/ no mufflers on my 460c.i. eff one fiddy...
that'll be fun...
for our rangers, though:
headers:y-pipe:pipe:muffler:pipe(s):tip(s)
tomorrow, i will be welding true duals w/ no mufflers on my 460c.i. eff one fiddy...
that'll be fun...
for our rangers, though:
headers:y-pipe:pipe:muffler:pipe(s):tip(s)
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From: OC, CA
For a while I had a magnaflow si/so muffler and retained all the stock piping and exited in the stock location. It didn't seem to to run any better, but it sounded a little deeper than stock. A couple weeks ago, I finally dumped it and to me it sounds much better dumped, but I think it hurt the bottom end a little bit. My honest opinion is stock sized piping to a si/so muffler and straight out the back with the same size piping as stock. These motors aren't very big, and they are in a low state of tune, and don't rev at all so that leads me to believe that big piping, dual exits, etc. will only hurt performance (TORQUE) and would require a slew of engine work (cam, head work, headers, TB, Int Man, etc)to get the motor to spin hard enough to take advantage of the added flow.
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From: Coal Region, MTC to be exact...heart of the coal region.
WRONG. backpressure is evil, end of the story. its when u boost the size in exhaust pipe u loose the exhaust velocity, that kills low end torque but helps high end power.
lets not forget here, a single exhaust of a slight larger size will just as much as a dual of lesser size. for a 4.0 OHV i would run at the most 2.25" single, 2.0 dual. for a SOHC, since it can breath better at a high rpm i would opt for a 2.5" single at the largest or 2.25" duals at the largest.
lets not forget here, a single exhaust of a slight larger size will just as much as a dual of lesser size. for a 4.0 OHV i would run at the most 2.25" single, 2.0 dual. for a SOHC, since it can breath better at a high rpm i would opt for a 2.5" single at the largest or 2.25" duals at the largest.
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From: OC, CA
Originally Posted by optikal illushun
WRONG. backpressure is evil, end of the story. its when u boost the size in exhaust pipe u loose the exhaust velocity, that kills low end torque but helps high end power.
lets not forget here, a single exhaust of a slight larger size will just as much as a dual of lesser size. for a 4.0 OHV i would run at the most 2.25" single, 2.0 dual. for a SOHC, since it can breath better at a high rpm i would opt for a 2.5" single at the largest or 2.25" duals at the largest.
lets not forget here, a single exhaust of a slight larger size will just as much as a dual of lesser size. for a 4.0 OHV i would run at the most 2.25" single, 2.0 dual. for a SOHC, since it can breath better at a high rpm i would opt for a 2.5" single at the largest or 2.25" duals at the largest.
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From: Indiana
Ok well I have decided on a single 2.25 pipe with a Flowmaster muffler. But I am still unsure on what kind of exit and tip I want. What do you guys think will look good? I kinda want something different.
Any ideas? Thanks. . .
Chris
Any ideas? Thanks. . .
Chris
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From: Coal Region, MTC to be exact...heart of the coal region.
Originally Posted by 3LiterBeater
No, your WRONG. Your contradicting yourself. You make absolutely no sense at all. Backpressure is your friend, our motors don't rev and make no good use of larger piping. Our motors are cammed and ported to make low end torque, bottom line. Big piping will hurt your low end torque and won't do anything for your top end with a motor that simply DOES NOT BREATH enough to spin hard. Get your facts straight before you tell me I'm wrong...
. larger exhaust pipe=less exhaust velocity. this makes the engine push harder to get the exhaust out, u loose scavenging ability.
Nope. Back pressure is an unavoidable evil, but it doesn't do any good. Whenever back pressure can be reduced, the engine can then be tuned to make more power, regardless of rpm range. This old wives tale persists because people will make a change in the exhaust system to reduce back pressure, and don't make the necessary tuning changes so they see an apparent reduction in torque simply because they didn't look at the engine as a complete system. If back pressure made more power you can bet that the top fuelers wouldn't be using those short little pipes that are huge diameter, and the WW11 fighter planes wouldn't have done the same thing.
What he said.
The reason people lose performance when they open up the exhaust is because increasing the diameter reduces the exhaust gas VELOCITY. If the gasses have less velocity they won't flow as well. You end up having to spin the engine a lot faster to get it up into the range where it is generating enough gas to make the system work, below that range you will have less performance.
Backpressure in a system is proportional to diameter^4 but velocity is proportional to diameter^2 so small changes in diameter give disproportionately large changes in back pressure. What this means is that you can significantly increase an engine's performance potential with only a small change in diameter.
The reason people lose performance when they open up the exhaust is because increasing the diameter reduces the exhaust gas VELOCITY. If the gasses have less velocity they won't flow as well. You end up having to spin the engine a lot faster to get it up into the range where it is generating enough gas to make the system work, below that range you will have less performance.
Backpressure in a system is proportional to diameter^4 but velocity is proportional to diameter^2 so small changes in diameter give disproportionately large changes in back pressure. What this means is that you can significantly increase an engine's performance potential with only a small change in diameter.
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From: OC, CA
Originally Posted by optikal illushun
How bout a big fat NO. u are still wrong bro. i dont see how u say im contridicting myself either .
larger exhaust pipe=less exhaust velocity. this makes the engine push harder to get the exhaust out, u loose scavenging ability.
. larger exhaust pipe=less exhaust velocity. this makes the engine push harder to get the exhaust out, u loose scavenging ability.
Originally Posted by optikal illushun
WRONG. backpressure is evil, end of the story. its when u boost the size in exhaust pipe u loose the exhaust velocity, that kills low end torque but helps high end power.
Originally Posted by optikal illushun
Whenever back pressure can be reduced, the engine can then be tuned to make more power, regardless of rpm range.
Originally Posted by optikal illushun
larger exhaust pipe=less exhaust velocity. this makes the engine push harder to get the exhaust out, u loose scavenging ability.
Originally Posted by Doug904
"on these small v6 engines , backpressure builds torque..."
Originally Posted by Fomocoedge
Ill take Dougs word for it.
