Could anyone tell me why a ramhorn manifold makes more power?
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Could anyone tell me why a ramhorn manifold makes more power?
Hey guys - i was just thinking about this today- Why does a ramhorn or top mount make more than a log manifold? Lets say your boosting 10psi, with properly functioning wastegate.
If both setups are doing 10psi, same turbo same everything, why would a ramhorn make more hp?
Is it due to the exhaust velocities? With a wastegate opening and shooting out extra exhaust velocities at a certain point, how does that make a difference?
thanks!
If both setups are doing 10psi, same turbo same everything, why would a ramhorn make more hp?
Is it due to the exhaust velocities? With a wastegate opening and shooting out extra exhaust velocities at a certain point, how does that make a difference?
thanks!
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Re: Could anyone tell me why a ramhorn manifold makes more power? (nytosc)
ramhorn or any long tube gives the air fuel mixture a longer distance to complete its burn process, thus creating more heat and velocity. On many cars a log will do fine with a properly matched turbo set up, but a well built small motor like a honda that can spin out 8-9k and a turbo to match will benifit from the extra distance over a log.
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Re: Could anyone tell me why a ramhorn manifold makes more power? (No Dig)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by No Dig »</TD></TR><TR><TD CLASS="quote">ramhorn or any long tube gives the air fuel mixture a longer distance to complete its burn process, thus creating more heat and velocity. On many cars a log will do fine with a properly matched turbo set up, but a well built small motor like a honda that can spin out 8-9k and a turbo to match will benifit from the extra distance over a log. </TD></TR></TABLE>
I dont understand that- burnt air and fuel is being shot out- into the manifold- Are you referring to the intake manifold?
I dont understand that- burnt air and fuel is being shot out- into the manifold- Are you referring to the intake manifold?
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Re: Could anyone tell me why a ramhorn manifold makes more power? (nytosc)
First of all, you need to understand how boost is created. Boost pressure (psi) is a measure of resistance in a system much like Ohms in an electrical circuit. The resistance in the head, manifold, and turbine create the measurement of PSI resistance.
Consider running a turbo wide open into open air, it creates no boost yet there still is air flow. Now put it into a closed system and it does create boost while the air volume stays the same. I hope this makes sense because its the basis of the rest of this explanation.
When someone runs a log manifold on a given turbo, lets say a 57trim, the turbo spools up to 10psi fast because the air flow inside the log manifold is very turbulent. This creates resistance and does not allow the engine to flow exhaust gas out as efficiently. This creates a backup of pressure thus boost pressure. When someone runs a more efficient ramhorn or topmount, there is less resistance in the manifold because of the true collector. This allows for more air flow with less resistance...basically more power with the same boost.
This same effect can be created with the use of a smaller turbine housing (.48, .63, .82, etc). Since air is channeled down into the smaller housing, air speeds up to compensate for the flow rate (i.e. Bernoulli's Principle) and accounts for a little of the gain. Theoretically if you were to have a small compressor on a turbo and a very large turbine, you could make tons of power (due to the gross air flow) without creating much if any boost pressure.
With a more efficient setup vs a less efficient setup, you can run the same amount of boost pressure while creating a ton more power because of the gross air flow rate. Since the more efficient setup creates less resistance on the air flowing into the engine and through the exhaust/turbine, it holds up the air less which allows for more air at a lower psi.
...i hope this makes sense. i've never been very good at explaining complicated things to people without pictures
Consider running a turbo wide open into open air, it creates no boost yet there still is air flow. Now put it into a closed system and it does create boost while the air volume stays the same. I hope this makes sense because its the basis of the rest of this explanation.
When someone runs a log manifold on a given turbo, lets say a 57trim, the turbo spools up to 10psi fast because the air flow inside the log manifold is very turbulent. This creates resistance and does not allow the engine to flow exhaust gas out as efficiently. This creates a backup of pressure thus boost pressure. When someone runs a more efficient ramhorn or topmount, there is less resistance in the manifold because of the true collector. This allows for more air flow with less resistance...basically more power with the same boost.
This same effect can be created with the use of a smaller turbine housing (.48, .63, .82, etc). Since air is channeled down into the smaller housing, air speeds up to compensate for the flow rate (i.e. Bernoulli's Principle) and accounts for a little of the gain. Theoretically if you were to have a small compressor on a turbo and a very large turbine, you could make tons of power (due to the gross air flow) without creating much if any boost pressure.
With a more efficient setup vs a less efficient setup, you can run the same amount of boost pressure while creating a ton more power because of the gross air flow rate. Since the more efficient setup creates less resistance on the air flowing into the engine and through the exhaust/turbine, it holds up the air less which allows for more air at a lower psi.
...i hope this makes sense. i've never been very good at explaining complicated things to people without pictures
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Re: (my2kgsr)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by my2kgsr »</TD></TR><TR><TD CLASS="quote">^ couldn't have said it better^</TD></TR></TABLE>
Lol...i'm sure someone could word that a little more eloquently, but the main point is still there. If it doesnt make sense to someone, i'll try rewrite it in a manner that is less rambling
Lol...i'm sure someone could word that a little more eloquently, but the main point is still there. If it doesnt make sense to someone, i'll try rewrite it in a manner that is less rambling
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Re: Could anyone tell me why a ramhorn manifold makes more power? (Schister66)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Schister66 »</TD></TR><TR><TD CLASS="quote">First of all, you need to understand how boost is created. Boost pressure (psi) is a measure of resistance in a system much like Ohms in an electrical circuit. The resistance in the head, manifold, and turbine create the measurement of PSI resistance.
Consider running a turbo wide open into open air, it creates no boost yet there still is air flow. Now put it into a closed system and it does create boost while the air volume stays the same. I hope this makes sense because its the basis of the rest of this explanation.
When someone runs a log manifold on a given turbo, lets say a 57trim, the turbo spools up to 10psi fast because the air flow inside the log manifold is very turbulent. This creates resistance and does not allow the engine to flow exhaust gas out as efficiently. This creates a backup of pressure thus boost pressure. When someone runs a more efficient ramhorn or topmount, there is less resistance in the manifold because of the true collector. This allows for more air flow with less resistance...basically more power with the same boost.
This same effect can be created with the use of a smaller turbine housing (.48, .63, .82, etc). Since air is channeled down into the smaller housing, air speeds up to compensate for the flow rate (i.e. Bernoulli's Principle) and accounts for a little of the gain. Theoretically if you were to have a small compressor on a turbo and a very large turbine, you could make tons of power (due to the gross air flow) without creating much if any boost pressure.
With a more efficient setup vs a less efficient setup, you can run the same amount of boost pressure while creating a ton more power because of the gross air flow rate. Since the more efficient setup creates less resistance on the air flowing into the engine and through the exhaust/turbine, it holds up the air less which allows for more air at a lower psi.
...i hope this makes sense. i've never been very good at explaining complicated things to people without pictures</TD></TR></TABLE>
So on a small setup say my 10psi b20 where the WG opens up at 3500RPMS, a WG position that flows the extra exhaust velocity would help out on the engine power?
Good info thanks!
Consider running a turbo wide open into open air, it creates no boost yet there still is air flow. Now put it into a closed system and it does create boost while the air volume stays the same. I hope this makes sense because its the basis of the rest of this explanation.
When someone runs a log manifold on a given turbo, lets say a 57trim, the turbo spools up to 10psi fast because the air flow inside the log manifold is very turbulent. This creates resistance and does not allow the engine to flow exhaust gas out as efficiently. This creates a backup of pressure thus boost pressure. When someone runs a more efficient ramhorn or topmount, there is less resistance in the manifold because of the true collector. This allows for more air flow with less resistance...basically more power with the same boost.
This same effect can be created with the use of a smaller turbine housing (.48, .63, .82, etc). Since air is channeled down into the smaller housing, air speeds up to compensate for the flow rate (i.e. Bernoulli's Principle) and accounts for a little of the gain. Theoretically if you were to have a small compressor on a turbo and a very large turbine, you could make tons of power (due to the gross air flow) without creating much if any boost pressure.
With a more efficient setup vs a less efficient setup, you can run the same amount of boost pressure while creating a ton more power because of the gross air flow rate. Since the more efficient setup creates less resistance on the air flowing into the engine and through the exhaust/turbine, it holds up the air less which allows for more air at a lower psi.
...i hope this makes sense. i've never been very good at explaining complicated things to people without pictures
</TD></TR></TABLE>So on a small setup say my 10psi b20 where the WG opens up at 3500RPMS, a WG position that flows the extra exhaust velocity would help out on the engine power?
Good info thanks!
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Re: Could anyone tell me why a ramhorn manifold makes more power? (nytosc)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nytosc »</TD></TR><TR><TD CLASS="quote">
So on a small setup say my 10psi b20 where the WG opens up at 3500RPMS, a WG position that flows the extra exhaust velocity would help out on the engine power?</TD></TR></TABLE>
No, not really. The turbine side still needs a certain amount of air to spool the compressor side up. The excess air leaving the wastegate after full boost is reached is merely to bleed off excess resistance from building behind the turbine. In a sense, i see what you're getting at, but it doesn't really help spool or engine performance. It keeps a static pressure on the turbine side during the higher flow (higher RPMs).
So on a small setup say my 10psi b20 where the WG opens up at 3500RPMS, a WG position that flows the extra exhaust velocity would help out on the engine power?</TD></TR></TABLE>
No, not really. The turbine side still needs a certain amount of air to spool the compressor side up. The excess air leaving the wastegate after full boost is reached is merely to bleed off excess resistance from building behind the turbine. In a sense, i see what you're getting at, but it doesn't really help spool or engine performance. It keeps a static pressure on the turbine side during the higher flow (higher RPMs).
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Re: Could anyone tell me why a ramhorn manifold makes more power? (Schister66)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Schister66 »</TD></TR><TR><TD CLASS="quote">
No, not really. The turbine side still needs a certain amount of air to spool the compressor side up. The excess air leaving the wastegate after full boost is reached is merely to bleed off excess resistance from building behind the turbine. In a sense, i see what you're getting at, but it doesn't really help spool or engine performance. It keeps a static pressure on the turbine side during the higher flow (higher RPMs). </TD></TR></TABLE>
You stated that its the lack of backpressure, and the smoother flowing gasses thats helping out the power.
So on a setup where its making low boost, and the wastegate is opening very soon, would having a efficient flowing WG placement on the manifold increase horsepower, because its reducing the backpressure, therefore allowing it to flow better?
No, not really. The turbine side still needs a certain amount of air to spool the compressor side up. The excess air leaving the wastegate after full boost is reached is merely to bleed off excess resistance from building behind the turbine. In a sense, i see what you're getting at, but it doesn't really help spool or engine performance. It keeps a static pressure on the turbine side during the higher flow (higher RPMs). </TD></TR></TABLE>
You stated that its the lack of backpressure, and the smoother flowing gasses thats helping out the power.
So on a setup where its making low boost, and the wastegate is opening very soon, would having a efficient flowing WG placement on the manifold increase horsepower, because its reducing the backpressure, therefore allowing it to flow better?
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I guess it may in a sense do that, but to be honest, i dont know for sure. I'm still trying to think about this in a way that i can figure out and then explain....it may take me a little while
I can see where you're coming from with that idea though. If you were to hit a point with a smaller turbo when the wastegate was open and the air flowed in and out more efficiently (with the lack of backpressure from the wastegate bleeding off), i dont see why it isn't feasable that it could flow more at the same PSI under those circumstances.
I'm thinking about this while typing so bare with me...
I can see where you're coming from with that idea though. If you were to hit a point with a smaller turbo when the wastegate was open and the air flowed in and out more efficiently (with the lack of backpressure from the wastegate bleeding off), i dont see why it isn't feasable that it could flow more at the same PSI under those circumstances.
I'm thinking about this while typing so bare with me...
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ramhorns flow better, the better the flow in an engine the greater the ve, greater ve = more power.
like was already said boost is only a measure of inability to flow, or restriction.
so the ramhorn will allow the system to flow better and there for increasing VE.
Now the wastegate will only limit boost its a simple peice, so regardless of the motor/setup's efficency its still going to regulate the same pressure (idealy, to make this simple)
Wastegate placement will only effect boost control not power (directly) an inefficient gate placement will cause spike/creep and won't regulate well.
Modified by akira712 at 9:41 PM 4/25/2008
like was already said boost is only a measure of inability to flow, or restriction.
so the ramhorn will allow the system to flow better and there for increasing VE.
Now the wastegate will only limit boost its a simple peice, so regardless of the motor/setup's efficency its still going to regulate the same pressure (idealy, to make this simple)
Wastegate placement will only effect boost control not power (directly) an inefficient gate placement will cause spike/creep and won't regulate well.
Modified by akira712 at 9:41 PM 4/25/2008
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Re: Could anyone tell me why a ramhorn manifold makes more power? (nytosc)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by No Dig »</TD></TR><TR><TD CLASS="quote">ramhorn or any long tube gives the air fuel mixture a longer distance to complete its burn process, thus creating more heat and velocity. On many cars a log will do fine with a properly matched turbo set up, but a well built small motor like a honda that can spin out 8-9k and a turbo to match will benifit from the extra distance over a log. </TD></TR></TABLE>
you are special.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nytosc »</TD></TR><TR><TD CLASS="quote">If both setups are doing 10psi, same turbo same everything, why would a ramhorn make more hp?thanks!</TD></TR></TABLE>
in that setup log will be a better choice. flame on.
Modified by zex_cool at 8:46 PM 4/25/2008
you are special.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nytosc »</TD></TR><TR><TD CLASS="quote">If both setups are doing 10psi, same turbo same everything, why would a ramhorn make more hp?thanks!</TD></TR></TABLE>
in that setup log will be a better choice. flame on.
Modified by zex_cool at 8:46 PM 4/25/2008
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Re: Could anyone tell me why a ramhorn manifold makes more power? (zex_cool)
Zex is right! And ramhorns have a ridiculus crappy flow compared to a mini ram or similAr... logs are fine in so many cases too.
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Re: Could anyone tell me why a ramhorn manifold makes more power? (nytosc)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nytosc »</TD></TR><TR><TD CLASS="quote">Hey guys - i was just thinking about this today</TD></TR></TABLE>
next time, think for more than 2 seconds before posting?
Mostly, the ramhorn has a true merge collector, piece of **** log doesn't. Therefore, the ramhorn is actually conducive to airflow, the log isn't.
next time, think for more than 2 seconds before posting?
Mostly, the ramhorn has a true merge collector, piece of **** log doesn't. Therefore, the ramhorn is actually conducive to airflow, the log isn't.
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Re: Could anyone tell me why a ramhorn manifold makes more power? (rorik)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rorik »</TD></TR><TR><TD CLASS="quote">
next time, think for more than 2 seconds before posting?
Mostly, the ramhorn has a true merge collector, piece of **** log doesn't. Therefore, the ramhorn is actually conducive to airflow, the log isn't.</TD></TR></TABLE>
Wait, did you read it?
Did you come out of your mothers womb, having immense knowledge on how a turbocharger works, and the different parameters that one can run, to have different power levels?
Is the log manifold really a piece of fecal matter?
Maybe you should think 2 seconds before posting rude comments
I was simply asking a question wow.
next time, think for more than 2 seconds before posting?
Mostly, the ramhorn has a true merge collector, piece of **** log doesn't. Therefore, the ramhorn is actually conducive to airflow, the log isn't.</TD></TR></TABLE>
Wait, did you read it?
Did you come out of your mothers womb, having immense knowledge on how a turbocharger works, and the different parameters that one can run, to have different power levels?
Is the log manifold really a piece of fecal matter?
Maybe you should think 2 seconds before posting rude comments
I was simply asking a question wow.
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Re: Could anyone tell me why a ramhorn manifold makes more power? (cfwthb_94)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by cfwthb_94 »</TD></TR><TR><TD CLASS="quote">if a log manifold is a piece of **** how come the inline pro one had made up 800hp?</TD></TR></TABLE>
it's not a true log manifold that's why
ask boosted hybrid from http://evans-tuning.com
it's not a true log manifold that's why
ask boosted hybrid from http://evans-tuning.com
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Re: Could anyone tell me why a ramhorn manifold makes more power? (cfwthb_94)
Look at the manifolds, an inline pro actually has runners that go towards the collector. most "log" manifolds have runners facing each other, flow very poorly and have skyhigh backpressure. Just look at it and you will see why one outperforms another.
Hint: "Flow" is a relative term.. Kooks/Ramhorm = increased CFM VOLUME of exhaust energy. Log/Short runner = increased CFM VELOCITY of exhaust energy.
*End Hint*
The way people are using FLOW in these posts, seems to confuse that principle. This is why its about the purpose of the use of that turbocharger, not just power only.
*End Hint*
The way people are using FLOW in these posts, seems to confuse that principle. This is why its about the purpose of the use of that turbocharger, not just power only.
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Re: Could anyone tell me why a ramhorn manifold makes more power? (nytosc)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nytosc »</TD></TR><TR><TD CLASS="quote">
I dont understand that- burnt air and fuel is being shot out- into the manifold- Are you referring to the intake manifold?
</TD></TR></TABLE>obviously it was over your head.<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by zex_cool »</TD></TR><TR><TD CLASS="quote">
you are special.
in that setup log will be a better choice. flame on.
Modified by zex_cool at 8:46 PM 4/25/2008</TD></TR></TABLE>
I believe in this case, you may be the special one. If you are unable to understand the fact that the af mix is continuing to complete its burn process after it exits the head and even throughout the turbo then you need to stay away from technical things. I can start belting out thermal dynamic equations if youd like.
Logs have downsides and upsides. They hold heat well, are good for a quick spool, but for high hp builds with a large turbo and high redline they arent the best choice.
I dont understand that- burnt air and fuel is being shot out- into the manifold- Are you referring to the intake manifold?
</TD></TR></TABLE>obviously it was over your head.<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by zex_cool »</TD></TR><TR><TD CLASS="quote">
you are special.
in that setup log will be a better choice. flame on.
Modified by zex_cool at 8:46 PM 4/25/2008</TD></TR></TABLE>
I believe in this case, you may be the special one. If you are unable to understand the fact that the af mix is continuing to complete its burn process after it exits the head and even throughout the turbo then you need to stay away from technical things. I can start belting out thermal dynamic equations if youd like.
Logs have downsides and upsides. They hold heat well, are good for a quick spool, but for high hp builds with a large turbo and high redline they arent the best choice.