topmout vs. ramhorn
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topmout vs. ramhorn
ok most topmounts are around the same price as ramhorn manifolds. i like the way topmounts look. so my plan is 300whp on a ls. would a topmount be pointless since its mostly for high hp setups. would it be better to just run the ramhorn or the topmount. which would get better whp.?
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Re: (urbansi)
ok thanks i want the one that will give me the most whp on my setup, so i was asking cause t he price was close and i like the way a top mount looks. but htanks for the replies.
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Re: (bigbadboy)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by bigbadboy »</TD></TR><TR><TD CLASS="quote">topmount > ramhorn > log</TD></TR></TABLE>
even on a 250-300whp stock ls? topmount would be the best.
even on a 250-300whp stock ls? topmount would be the best.
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Re: (tgh99si)
I havent seen any deffinative numbers for topmont vs. ramhorn, but supposidly the topmount flows better. Main reason for getting the topmount though are ability to use a 4" DP and ease of access to the turbo.
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personally i woudl think the top mount woudl make less on the same sized gt30r turbo than the ram due to it's longer runners and lack of exhaust buildup needed to help spool the turbo. if the turbo was a big assed turbo, then i can see it's benefits, but on a 300 hp car? or even under 500 it;s pointless in my opinion.
now mind u i've never worked with a top mount so it's a guess, but i woudl imagine i'm pretty close to correct.
now mind u i've never worked with a top mount so it's a guess, but i woudl imagine i'm pretty close to correct.
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Re: topmout vs. ramhorn (mra4886)
Since people seem to think all top mounts and ramhorns are the same, tell me why one would make more power than the other, in general? Same diameter runners, same collector. Different brands have different length runners. So what makes topmounts "better" in general?
Re: (tgh99si)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tgh99si »</TD></TR><TR><TD CLASS="quote">can someone give some reasons why a topmount makes more power than a ramhorn?</TD></TR></TABLE>
Top mount manifolds are better for high end power, the longer runners allow for better breathing up top. Same principal as with a 4-2-1 header and a 4-1 header. the 4-2-1 like the ram horn is shorter sections which will give you better spooling and mid range power
the 4-1 header like the top mount has long runners which allow better breathing up top in the higher rpm range. if your trying to keep it a daily driver realistically either manifold will work for you. if you like th ebling factor of a top mount then buy one of those but either manifold will give you pretty much the same results with the goal you have in range. if you plan on going big in the future then the top mount would be the way to go
Top mount manifolds are better for high end power, the longer runners allow for better breathing up top. Same principal as with a 4-2-1 header and a 4-1 header. the 4-2-1 like the ram horn is shorter sections which will give you better spooling and mid range power
the 4-1 header like the top mount has long runners which allow better breathing up top in the higher rpm range. if your trying to keep it a daily driver realistically either manifold will work for you. if you like th ebling factor of a top mount then buy one of those but either manifold will give you pretty much the same results with the goal you have in range. if you plan on going big in the future then the top mount would be the way to go
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Re: topmout vs. ramhorn (tony1)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tegedrex »</TD></TR><TR><TD CLASS="quote">Main reason for getting the topmount though are ability to use a 4" DP and ease of access to the turbo. </TD></TR></TABLE>
is anyone running a 4" downpipe with a ramhorn?
is anyone running a 4" downpipe with a ramhorn?
Re: topmout vs. ramhorn (tgh99si)
it might be able to be done but its a pretty tight radius to try and make a 4" on a ramhorn unless you were just running it out the front side bumper then that would be wicked easy 
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top mount gives a quicker spool but i think it wouldn't be a good idea if you arn't pushing out a lot of power i'd say 300whp areas would be good enough for even a log manifold and the extra money just build your bottom end IMO
Re: (snaileg)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by snaileg »</TD></TR><TR><TD CLASS="quote">top mount gives a quicker spool but i think it wouldn't be a good idea if you arn't pushing out a lot of power i'd say 300whp areas would be good enough for even a log manifold and the extra money just build your bottom end IMO</TD></TR></TABLE>
top mount slower spool longer runners bud, shorter runners quicker spool.
top mount slower spool longer runners bud, shorter runners quicker spool.
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Re: topmout vs. ramhorn (mra4886)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JDMs1eeper »</TD></TR><TR><TD CLASS="quote">
The exhaust temps are very high at this area so the expanded gases will need to work much hard when passing that first turns than any other turn of the exhaust system. These will result in less reverse flow, or exhaust gas reversion after top dead center, and will make the inertial scavenging towards the end of the cycle. The exhaust gasses that occupy the clearance volume will be carried around into the following intake stroke. As you can see, even at 100% volumetric efficiency the mixture will still only be 89.6% fresh intake charge. If the chamber pressure does not reach atmospheric by the end of the cycle, this 10.6 %, or 4.66 cubic inches of exhaust gasses will be pressurized, and will take up even more space once they are allowed to expand as the chamber volume increases during the intake stroke. If the exhaust backs up at this point of the exhaust, this will reduce volumetric efficiency considerably. This is because the exhaust gasses will occupy space that could be used for fresh mixture. These exhaust gasses effectively "take away" from the swept volume, or displacement of the motor. The main object to the exhaust system then, should be to evacuate as much of the spent gasses as possible, thus the reason why we use larger turbines, merge collectors,longer equal length turbo manifolds like the topmount and large 3” to 4” exhaust systems.
</TD></TR></TABLE>
answered this only a week or 2 ago
Topmounts > Ram > Log as some1 already said. A topmount will always benifit you no matter what setup. Remember also, like i stated before but something to add. The more cleared exhaust gasses from the combustion chamber the more it lowers chance of knock also, and CAN allow more horsepower on a lower octane such as 91-93 VS if you had a Log.
Also something to add. This is also why it’s a “great" idea to run an effective dump tube setup. An example of how exhaust gas can hurt performance can be found on Jeff Evans website. They have made I believe 60+whp just by adding a dumb tube on a boosted setup he was dyno’ing.
As for manifold choice, its like buying a car. Do you want a NSX or do you want a Civic? You get what you pay for and you get what you can afford at the time.
Modified by JDMs1eeper at 1:53 PM 9/9/2006
The exhaust temps are very high at this area so the expanded gases will need to work much hard when passing that first turns than any other turn of the exhaust system. These will result in less reverse flow, or exhaust gas reversion after top dead center, and will make the inertial scavenging towards the end of the cycle. The exhaust gasses that occupy the clearance volume will be carried around into the following intake stroke. As you can see, even at 100% volumetric efficiency the mixture will still only be 89.6% fresh intake charge. If the chamber pressure does not reach atmospheric by the end of the cycle, this 10.6 %, or 4.66 cubic inches of exhaust gasses will be pressurized, and will take up even more space once they are allowed to expand as the chamber volume increases during the intake stroke. If the exhaust backs up at this point of the exhaust, this will reduce volumetric efficiency considerably. This is because the exhaust gasses will occupy space that could be used for fresh mixture. These exhaust gasses effectively "take away" from the swept volume, or displacement of the motor. The main object to the exhaust system then, should be to evacuate as much of the spent gasses as possible, thus the reason why we use larger turbines, merge collectors,longer equal length turbo manifolds like the topmount and large 3” to 4” exhaust systems.
</TD></TR></TABLE>answered this only a week or 2 ago
Topmounts > Ram > Log as some1 already said. A topmount will always benifit you no matter what setup. Remember also, like i stated before but something to add. The more cleared exhaust gasses from the combustion chamber the more it lowers chance of knock also, and CAN allow more horsepower on a lower octane such as 91-93 VS if you had a Log.
Also something to add. This is also why it’s a “great" idea to run an effective dump tube setup. An example of how exhaust gas can hurt performance can be found on Jeff Evans website. They have made I believe 60+whp just by adding a dumb tube on a boosted setup he was dyno’ing.
As for manifold choice, its like buying a car. Do you want a NSX or do you want a Civic? You get what you pay for and you get what you can afford at the time.
Modified by JDMs1eeper at 1:53 PM 9/9/2006
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Re: topmout vs. ramhorn (JDMs1eeper)
Top mount, bottom mount, ******* trunk mount....
The turbo doesn't know where it is, nor does the engine know which way the runners go. The engine knows what diameter runners there are, how long they are, how many bends are in each runner, what type of collector, and what size downpipe there is. There is no "top mount is better than ramhorn", because not all top mounts perform the same. At least most ramhorn manifolds have the same design and assuming the collectors are good and pipes fit up good with no edges overhanging anywhere restricting flow, they will make similar power. "top mount" manifolds are all designed differently. Most people just run the tubes the easiest route, which does not give equal restriction or length per runner. The full race top mount is what started it all, and it DOES make more power than the ramhorn, but not because the turbo sits on the top. It's because the runners the the right length (not long vs. short, it's optimal vs. not) for a high hp b series, and they are equal length with the same amount of bends per runner, creating equal pressure loss per runner. I have yet to see another manufacturer do the same. Most like to take advantage of the fact that full race top mounts make more power than ramhorns, and say hey, "here's my topmount" "they make more power than ramhorns" "look at all the fast drag racer's using them". IT'S NOT ABOUT TOP OR BOTTOM MOUNT, IT'S ABOUT MANIFOLD DESIGN.....
And for what it's worth, i've done 4" downpipes on "ramhorn" manifolds plenty of times...
The turbo doesn't know where it is, nor does the engine know which way the runners go. The engine knows what diameter runners there are, how long they are, how many bends are in each runner, what type of collector, and what size downpipe there is. There is no "top mount is better than ramhorn", because not all top mounts perform the same. At least most ramhorn manifolds have the same design and assuming the collectors are good and pipes fit up good with no edges overhanging anywhere restricting flow, they will make similar power. "top mount" manifolds are all designed differently. Most people just run the tubes the easiest route, which does not give equal restriction or length per runner. The full race top mount is what started it all, and it DOES make more power than the ramhorn, but not because the turbo sits on the top. It's because the runners the the right length (not long vs. short, it's optimal vs. not) for a high hp b series, and they are equal length with the same amount of bends per runner, creating equal pressure loss per runner. I have yet to see another manufacturer do the same. Most like to take advantage of the fact that full race top mounts make more power than ramhorns, and say hey, "here's my topmount" "they make more power than ramhorns" "look at all the fast drag racer's using them". IT'S NOT ABOUT TOP OR BOTTOM MOUNT, IT'S ABOUT MANIFOLD DESIGN.....
And for what it's worth, i've done 4" downpipes on "ramhorn" manifolds plenty of times...
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Re: (snaileg)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by snaileg »</TD></TR><TR><TD CLASS="quote">top mount gives a quicker spool but i think it wouldn't be a good idea if you arn't pushing out a lot of power i'd say 300whp areas would be good enough for even a log manifold and the extra money just build your bottom end IMO</TD></TR></TABLE>
+
also, i agree with "tony1" it shouldn't matter what direction the gases are flowing. what matters is the design.
Modified by hks85 at 12:47 PM 9/9/2006
+
also, i agree with "tony1" it shouldn't matter what direction the gases are flowing. what matters is the design.
Modified by hks85 at 12:47 PM 9/9/2006
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Re: (hks85)
thats the difference between an undivided topmount VS divided top mount. now just need some1 to post up differences between the top mount and ram horn but as stated before no matter wat application the top mount ownes all
Modified by bigbadboy at 7:55 PM 9/9/2006
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Re: (TurboJesse)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TurboJesse »</TD></TR><TR><TD CLASS="quote">What about a front mount? since we have trunk mount manifolds now? 
</TD></TR></TABLE>
actually this just made me think of this... is anyone mounting the turbo (would have to be on a ramhorn obviously) like they do in pro classes, so the inlet is facing the front. is anyone doing this on a sfwd? might not be enough room for the downpipe with the core support there.
tell me if my imagination is going to far
</TD></TR></TABLE>actually this just made me think of this... is anyone mounting the turbo (would have to be on a ramhorn obviously) like they do in pro classes, so the inlet is facing the front. is anyone doing this on a sfwd? might not be enough room for the downpipe with the core support there.
tell me if my imagination is going to far
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Re: (bigbadboy)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by bigbadboy »</TD></TR><TR><TD CLASS="quote">but as stated before no matter wat application the top mount ownes all</TD></TR></TABLE>
Is it really that hard to understand?
Is it really that hard to understand?
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Re: (tgh99si)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tgh99si »</TD></TR><TR><TD CLASS="quote">
actually this just made me think of this... is anyone mounting the turbo (would have to be on a ramhorn obviously) like they do in pro classes, so the inlet is facing the front. is anyone doing this on a sfwd? might not be enough room for the downpipe with the core support there.
tell me if my imagination is going to far</TD></TR></TABLE>
Wait till you see what Jesse has cooking...
It's not a top mount though, so it won't be all that great...
actually this just made me think of this... is anyone mounting the turbo (would have to be on a ramhorn obviously) like they do in pro classes, so the inlet is facing the front. is anyone doing this on a sfwd? might not be enough room for the downpipe with the core support there.
tell me if my imagination is going to far</TD></TR></TABLE>
Wait till you see what Jesse has cooking...
It's not a top mount though, so it won't be all that great...
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Re: (tony1)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tony1 »</TD></TR><TR><TD CLASS="quote">
Wait till you see what Jesse has cooking...
It's not a top mount though, so it won't be all that great... </TD></TR></TABLE>
but it has the same amount of bends per runner also....and a pretty nice merge collector, its also light
Should work well with that new GT35r/42r hybrid
Wait till you see what Jesse has cooking...
It's not a top mount though, so it won't be all that great...
</TD></TR></TABLE>but it has the same amount of bends per runner also....and a pretty nice merge collector, its also light
Should work well with that new GT35r/42r hybrid