exhaust and another question
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exhaust and another question
i want to put on a 2" exhaust and upgrade the muffler but i don't want a fart can. is there any type of muffler that won't make it sound like i'm driving with a trunk full of pissed off bumble bees? second question, would there be any advantage to side gapping my spark plugs when i decide to swap them out?
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It will allow for a more complete combustion. I just haven't spent the time to do it, lol. If you do side-gap and all is well, let me know. I'll give it a go the next plug change.
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From: Clermont, Fl
If you keep it a single exhaust the 2.5" won't be to much of a factor but if you go duals with the 2.5" that's where the back pressure will matter. 2.25" with duals you should be fine considering it's not true duals. I'm not a mechanic by any means so don't quote me on anything. I belong to any other forum for Mustangs and there is a guy there that is as smart as all hell ... here's a link to his "garage" I'd suggest joining to ask him stuff, he knows what he's talking about and he's a good guy. He'll help if he can http://www.moddedmustangs.com/forums/member.php?u=31163
I actually shot him a private message and I should get one back tomorrow .. I'll post his answer as soon as I get it ...
I actually shot him a private message and I should get one back tomorrow .. I'll post his answer as soon as I get it ...
Last edited by TaterTodd; Feb 15, 2011 at 01:33 AM.
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alright thanks, i'll probably hop on that forum too. i'd only do a single exhaust on it. my wife drives it half the time so i'm not looking to do anything major to it. i belong to an F150 forum but there's a big difference between the 302 in my truck and the 2.0L neon engine..
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From: Clermont, Fl
I asked one fo the guys from my mustang forum and this was the response ... I appologize if you get lost reading through it. I hope this helps out and doesn't get you lost ...
Good question Todd, sorry for the long answer, but I know that you are a smart guy and can appreciate a better understanding of this.
First off I would like to address back pressure. There is no such thing as the proper amount of back pressure. When you are dealing with gas engines, in order to achieve the best efficiency, it is ideal to provide the least amount of resistance (back pressure) for the gases to be exchanged in and out of the engine, balanced against an ideal gas velocity. We need velocity to provide momentum. Force and momentum are related as you may all ready know. A guy named Isaac Newton figured this out in the 17th century and stated it like this:
Force = mass x (velocity / time)
It is hard to think of air or exhaust gas as having a lot of momentum, but if you think about the force that a hurricane imparts on a standing object, you will quickly agree that it has tremendous potential force.
Engineers manipulate gas velocities, to pull exhaust gasses out and intake gasses into an engine, by carefully sizing the diameters of the intake and exhaust systems of the engine. The length of the individual primary exhaust pipes and the diameter of those pipes and any sharp bends in the piping, all have a pronounced affect on how well and how fast gasses move through the system.
The highest exhaust gas velocities in an engine, occur about 1-2” after the exhaust valve and slowly diminish from there, in most exhaust systems. It is widely agreed upon in engineering circles, that 240-250 feet per second is close to an ideal velocity for exhaust gasses leaving the engine. Many clever designs have been attempted over the years, to build a system that can maintain these values through all engine speeds. You probably all ready guessed that these speeds aren’t constant in your engine. You would be right.
Good question Todd, sorry for the long answer, but I know that you are a smart guy and can appreciate a better understanding of this.
First off I would like to address back pressure. There is no such thing as the proper amount of back pressure. When you are dealing with gas engines, in order to achieve the best efficiency, it is ideal to provide the least amount of resistance (back pressure) for the gases to be exchanged in and out of the engine, balanced against an ideal gas velocity. We need velocity to provide momentum. Force and momentum are related as you may all ready know. A guy named Isaac Newton figured this out in the 17th century and stated it like this:
Force = mass x (velocity / time)
It is hard to think of air or exhaust gas as having a lot of momentum, but if you think about the force that a hurricane imparts on a standing object, you will quickly agree that it has tremendous potential force.
Engineers manipulate gas velocities, to pull exhaust gasses out and intake gasses into an engine, by carefully sizing the diameters of the intake and exhaust systems of the engine. The length of the individual primary exhaust pipes and the diameter of those pipes and any sharp bends in the piping, all have a pronounced affect on how well and how fast gasses move through the system.
The highest exhaust gas velocities in an engine, occur about 1-2” after the exhaust valve and slowly diminish from there, in most exhaust systems. It is widely agreed upon in engineering circles, that 240-250 feet per second is close to an ideal velocity for exhaust gasses leaving the engine. Many clever designs have been attempted over the years, to build a system that can maintain these values through all engine speeds. You probably all ready guessed that these speeds aren’t constant in your engine. You would be right.