Re: truck exhaust
Very well, perhaps I was a little too "straight-forward".
Very well, perhaps I was a little too "straight-forward".
- Thread starter black_ump
- Start date
Re: truck exhaust
You don't want a straight thru exhaust on a gas engine. Otherwise known as straight piping.... it will make you crazy and everyone will hate you.
On a diesel.... ok.
You don't want a straight thru exhaust on a gas engine. Otherwise known as straight piping.... it will make you crazy and everyone will hate you.
On a diesel.... ok.
Re: truck exhaust
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: KYS338</div><div class="ubbcode-body">You don't want a straight thru exhaust on a gas engine. Otherwise known as straight piping.... it will make you crazy and everyone will hate you.
On a diesel.... ok. </div></div>
Too late.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: KYS338</div><div class="ubbcode-body">You don't want a straight thru exhaust on a gas engine. Otherwise known as straight piping.... it will make you crazy and everyone will hate you.
On a diesel.... ok. </div></div>
Too late.
Re: truck exhaust
He's still wet behind the ears Tony, and barely has his fingers licked dry from Sally Rottencrotch
He's still wet behind the ears Tony, and barely has his fingers licked dry from Sally Rottencrotch
Re: truck exhaust
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Shot In The Dark</div><div class="ubbcode-body">Free flowing exhaust reduces scavenging and in turn your low end torque dies. </div></div>
Actually back pressure DECREASES scavenging, therefor a free flowing exhaust would theoretically increase scavenging. Better scavenging leads to better combustion (IE volumetric efficiency) which would theoretically lead to better mileage, but (as has been stated before) adding a free flowing muffler alone wont do much of anything. FYI headers would have much more effect on scavenging than a muffler. And on a completely unrelated note, Torque is measure HP is calculated. (Apparently very few people understand this.)
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Shot In The Dark</div><div class="ubbcode-body">Free flowing exhaust reduces scavenging and in turn your low end torque dies. </div></div>
Actually back pressure DECREASES scavenging, therefor a free flowing exhaust would theoretically increase scavenging. Better scavenging leads to better combustion (IE volumetric efficiency) which would theoretically lead to better mileage, but (as has been stated before) adding a free flowing muffler alone wont do much of anything. FYI headers would have much more effect on scavenging than a muffler. And on a completely unrelated note, Torque is measure HP is calculated. (Apparently very few people understand this.)
Re: truck exhaust
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 396chevy</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Shot In The Dark</div><div class="ubbcode-body">Free flowing exhaust reduces scavenging and in turn your low end torque dies. </div></div>
Actually back pressure DECREASES scavenging, therefor a free flowing exhaust would theoretically increase scavenging. Better scavenging leads to better combustion (IE volumetric efficiency) which would theoretically lead to better mileage, but (as has been stated before) adding a free flowing muffler alone wont do much of anything. FYI headers would have much more effect on scavenging than a muffler. And on a completely unrelated note, Torque is measure HP is calculated. (Apparently very few people understand this.) </div></div>
That is the general idea and would be the case in a tuned system however when applied to a bolt on giant exhaust like black_ump is looking at you actually see the reverse. The low pressure we would see leaving the combustion chamber is negated by the volume of turbulent gas slowly (slow, relative to the intake pulse) moving through the large exhaust. Remember scavenging takes place in two parts, there is the intake side and the exhaust side. So in a system like black_ump is talking about the low pressure we would usually see on a normal exhaust is replaced with a turbulent slow moving mass (think higher back-pressure) and the intake charge suffers. You have to have a tuned exhaust system where the air mass leaving the exhaust is flowing faster than the intake flow in order to increase scavenging. That's why you see old schoolers using header wrap to keep the heat in the pipes and by doing this they decrease the turbulence within the system. Simply adding a huge exhaust and thinking that you're reducing back-pressure isn't always the case especially when you go over-board like Black_um is talking about. On a side note, back-pressure and low scavenging has been shown to increase comp ratios slightly and in some cases enough to more than compensate for the lack of scavenging's higher volumetric efficiency.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 396chevy</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Shot In The Dark</div><div class="ubbcode-body">Free flowing exhaust reduces scavenging and in turn your low end torque dies. </div></div>
Actually back pressure DECREASES scavenging, therefor a free flowing exhaust would theoretically increase scavenging. Better scavenging leads to better combustion (IE volumetric efficiency) which would theoretically lead to better mileage, but (as has been stated before) adding a free flowing muffler alone wont do much of anything. FYI headers would have much more effect on scavenging than a muffler. And on a completely unrelated note, Torque is measure HP is calculated. (Apparently very few people understand this.) </div></div>
That is the general idea and would be the case in a tuned system however when applied to a bolt on giant exhaust like black_ump is looking at you actually see the reverse. The low pressure we would see leaving the combustion chamber is negated by the volume of turbulent gas slowly (slow, relative to the intake pulse) moving through the large exhaust. Remember scavenging takes place in two parts, there is the intake side and the exhaust side. So in a system like black_ump is talking about the low pressure we would usually see on a normal exhaust is replaced with a turbulent slow moving mass (think higher back-pressure) and the intake charge suffers. You have to have a tuned exhaust system where the air mass leaving the exhaust is flowing faster than the intake flow in order to increase scavenging. That's why you see old schoolers using header wrap to keep the heat in the pipes and by doing this they decrease the turbulence within the system. Simply adding a huge exhaust and thinking that you're reducing back-pressure isn't always the case especially when you go over-board like Black_um is talking about. On a side note, back-pressure and low scavenging has been shown to increase comp ratios slightly and in some cases enough to more than compensate for the lack of scavenging's higher volumetric efficiency.
Re: truck exhaust
If you are running LESS THAN 500hp, you cannot use a 3" system effeciantly. Stick with a 2.25" system, especially in a six so you don't lose proper scavenging. Of course if you want to be that dumbass, go for the biggest 3" - 4" tubed system you can find and rock the paint can tip.
A true performance based system will include headers, merge collectors, and no larger than a 2.25" tube exiting through a free flowing muffler for teh street. This will not only give a proper performance sound, it will serve teh vehicle better by scavenging the exhaust nicer, and actually showing a 5% - 7% increase in performance. As to better fuel effenciay...HA, it's performance it's gonna cost you!
If you are running LESS THAN 500hp, you cannot use a 3" system effeciantly. Stick with a 2.25" system, especially in a six so you don't lose proper scavenging. Of course if you want to be that dumbass, go for the biggest 3" - 4" tubed system you can find and rock the paint can tip.
A true performance based system will include headers, merge collectors, and no larger than a 2.25" tube exiting through a free flowing muffler for teh street. This will not only give a proper performance sound, it will serve teh vehicle better by scavenging the exhaust nicer, and actually showing a 5% - 7% increase in performance. As to better fuel effenciay...HA, it's performance it's gonna cost you!
Re: truck exhaust
also remember, you dont gain much by being able to push huge amounts of exhaust gas out if you arent drawing in any more air. each modification in the intake and exhaust arena will compliment the other. if you want to gain power and mpgs, you need a full system. a good intake, not a k&n oil charged pos. then headers and a free flowing exhaust. free flowing doesnt mean straight pipes. you can get high flow catalytic converters and mufflers from any exhaust manufacturer. get a kit made for your vehicle with mandrel bends. if more power and economy is what you want this is how you will get it. also after you do all of then, then have a look at getting a custom tune made for your vehicle that includes these mods. it will be like having a whole new truck.like above, stick with a 2.25 pipe.
also remember, you dont gain much by being able to push huge amounts of exhaust gas out if you arent drawing in any more air. each modification in the intake and exhaust arena will compliment the other. if you want to gain power and mpgs, you need a full system. a good intake, not a k&n oil charged pos. then headers and a free flowing exhaust. free flowing doesnt mean straight pipes. you can get high flow catalytic converters and mufflers from any exhaust manufacturer. get a kit made for your vehicle with mandrel bends. if more power and economy is what you want this is how you will get it. also after you do all of then, then have a look at getting a custom tune made for your vehicle that includes these mods. it will be like having a whole new truck.like above, stick with a 2.25 pipe.
Re: truck exhaust
One of my best friends has owned an exhaust shop for over twenty years and he turns people away who come in with 6 and 10 cylinder engines. He says for some reason vehicles with an odd number of cylinders on each side will not sound good and he just sends them down to the local midas. Get out there and listen to a few of the 6 cylinders and you can hear how awful they sound compared to a good V8. Hell alot of 4 cylinder vehicles will sound better.
One of my best friends has owned an exhaust shop for over twenty years and he turns people away who come in with 6 and 10 cylinder engines. He says for some reason vehicles with an odd number of cylinders on each side will not sound good and he just sends them down to the local midas. Get out there and listen to a few of the 6 cylinders and you can hear how awful they sound compared to a good V8. Hell alot of 4 cylinder vehicles will sound better.
Re: truck exhaust
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LWILLIAMS</div><div class="ubbcode-body">One of my best friends has owned an exhaust shop for over twenty years and he turns people away who come in with 6 and 10 cylinder engines. He says for some reason vehicles with an odd number of cylinders on each side will not sound good and he just sends them down to the local midas. Get out there and listen to a few of the 6 cylinders and you can hear how awful they sound compared to a good V8. Hell alot of 4 cylinder vehicles will sound better. </div></div>
Yep, If you've ever head a Viper rolling down the street you'll know just how true this statement is. I took one around a track in Pahrump NV and they sound just as bad in the car as they do outside.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LWILLIAMS</div><div class="ubbcode-body">One of my best friends has owned an exhaust shop for over twenty years and he turns people away who come in with 6 and 10 cylinder engines. He says for some reason vehicles with an odd number of cylinders on each side will not sound good and he just sends them down to the local midas. Get out there and listen to a few of the 6 cylinders and you can hear how awful they sound compared to a good V8. Hell alot of 4 cylinder vehicles will sound better. </div></div>
Yep, If you've ever head a Viper rolling down the street you'll know just how true this statement is. I took one around a track in Pahrump NV and they sound just as bad in the car as they do outside.
Re: truck exhaust
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LWILLIAMS</div><div class="ubbcode-body">One of my best friends has owned an exhaust shop for over twenty years and he turns people away who come in with 6 and 10 cylinder engines. He says for some reason vehicles with an odd number of cylinders on each side will not sound good and he just sends them down to the local midas. Get out there and listen to a few of the 6 cylinders and you can hear how awful they sound compared to a good V8. Hell alot of 4 cylinder vehicles will sound better.</div></div>
Huh, that's interesting. I've noticed that on Vipers and obviously on various V6 automobiles, but had never heard that it was due to the odd number of cylinders. I can tell you that I don't understand why that is, but now that you mention it, that does seem to be the case.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LWILLIAMS</div><div class="ubbcode-body">One of my best friends has owned an exhaust shop for over twenty years and he turns people away who come in with 6 and 10 cylinder engines. He says for some reason vehicles with an odd number of cylinders on each side will not sound good and he just sends them down to the local midas. Get out there and listen to a few of the 6 cylinders and you can hear how awful they sound compared to a good V8. Hell alot of 4 cylinder vehicles will sound better.</div></div>
Huh, that's interesting. I've noticed that on Vipers and obviously on various V6 automobiles, but had never heard that it was due to the odd number of cylinders. I can tell you that I don't understand why that is, but now that you mention it, that does seem to be the case.
Re: truck exhaust
Well, I've got a V10. It sounds fine to me with the factory exhaust - not that I care.
Well, I've got a V10. It sounds fine to me with the factory exhaust - not that I care.
Re: truck exhaust
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: offroadr1</div><div class="ubbcode-body">also remember, you dont gain much by being able to push huge amounts of exhaust gas out if you arent drawing in any more air. each modification in the intake and exhaust arena will compliment the other. if you want to gain power and mpgs, you need a full system. a good intake, not a k&n oil charged pos. then headers and a free flowing exhaust. free flowing doesnt mean straight pipes. you can get high flow catalytic converters and mufflers from any exhaust manufacturer. get a kit made for your vehicle with mandrel bends. if more power and economy is what you want this is how you will get it. also after you do all of then, then have a look at getting a custom tune made for your vehicle that includes these mods. it will be like having a whole new truck.like above, stick with a 2.25 pipe. </div></div>
When you add the custom tuned 'black box' stuff to a godd flowing intake and exhaust system on most any motor, it will usually mean running the 92/93 Octane to get the most power and take advantage of the systems.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: offroadr1</div><div class="ubbcode-body">also remember, you dont gain much by being able to push huge amounts of exhaust gas out if you arent drawing in any more air. each modification in the intake and exhaust arena will compliment the other. if you want to gain power and mpgs, you need a full system. a good intake, not a k&n oil charged pos. then headers and a free flowing exhaust. free flowing doesnt mean straight pipes. you can get high flow catalytic converters and mufflers from any exhaust manufacturer. get a kit made for your vehicle with mandrel bends. if more power and economy is what you want this is how you will get it. also after you do all of then, then have a look at getting a custom tune made for your vehicle that includes these mods. it will be like having a whole new truck.like above, stick with a 2.25 pipe. </div></div>
When you add the custom tuned 'black box' stuff to a godd flowing intake and exhaust system on most any motor, it will usually mean running the 92/93 Octane to get the most power and take advantage of the systems.
Re: truck exhaust
My buddy cant tell me why they sound so funky either just knows with a free flowing louder exhaust they dont sound good at all. Factory exhaust quiets them down enough its not noticable I guess.
My buddy cant tell me why they sound so funky either just knows with a free flowing louder exhaust they dont sound good at all. Factory exhaust quiets them down enough its not noticable I guess.
Re: truck exhaust
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LWILLIAMS</div><div class="ubbcode-body">My buddy cant tell me why they sound so funky either just knows with a free flowing louder exhaust they dont sound good at all. Factory exhaust quiets them down enough its not noticable I guess. </div></div>
It's gotta have something to do with the harmonics of the exhaust pulses because they all sound bad pointing to a V10 issue and not an exhaust issue.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LWILLIAMS</div><div class="ubbcode-body">My buddy cant tell me why they sound so funky either just knows with a free flowing louder exhaust they dont sound good at all. Factory exhaust quiets them down enough its not noticable I guess. </div></div>
It's gotta have something to do with the harmonics of the exhaust pulses because they all sound bad pointing to a V10 issue and not an exhaust issue.
Re: truck exhaust
Probably not going to get any better MPG's out of a V6 and it will probably sound horrible as well. Most generic V6's aren't intended to run with aftermarket exhaust systems as they don't do much for performance.
Probably not going to get any better MPG's out of a V6 and it will probably sound horrible as well. Most generic V6's aren't intended to run with aftermarket exhaust systems as they don't do much for performance.
