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Anyone make or have made a ram air style pipe extruding from bike with a cone filter.i want to ditch my stock air box assembly and thought it would look good to have an intake elbow exiting past the horn cover(once removed) and facing forward with a cone filter.
Much appreciate any feedback and details thanks.
 

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you have freer flowing pipes and AF? Have you tuned it?

like posted-maybe why not go topless, dremel the edges off the bottom of the AirBox (bottomless), mod up the 2 holes that hold the front of the AB cover, lifting it an inch to let more air in around the edges?
 

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Swampboogie Doug - that right there is some funny stuff ! 08rod I'm working on a Ram Air setup for my N/A V Rod that will retain the stock airbox, but I've never heard of one with an external filter and an elbow duct to the throttle bodies and I don't think it would be even worth doing. The stock airbox is actually quite efficient and most dyno runs guys here on the site have done the engine only gains a Hp or two without it and that's with no filters on the velocity stacks - which you can't even run on the street without sucking in dirt. You can cut holes in the bottom off the air filter housing if you want to like the template for S/E Cams Kit but to me that just lets hot air in from the engine or go Motohooligan Airbox but no real performance gains are seen. Welcome to the wish I had a Turbo or Supercharger club !
 

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I've had thoughts about ditching the airbox and installing a Hilborn type scoop atop the stacks with a filter inside. Don't know how well it would work but it might look cool.
 

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Who's gonna install the Hilborn Scoop first ?

WOW I'd love to see that Hilborn scoop mounted up - just mount it high enough to get ram air from above the handlebar height ! :notworth: I always wondered why some wild & crazy V Rodder never did anything with velocity stacks and a clear airbox cover area where you could see them down in there - or a scoop - What the Hell the bikes 17 years along, black finned or chrome scoops on Summit Racing only $ 100-150 just need to fab up a mount so it's time ! :D
 

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Personally I would like to try to make the vents functional. run some duct work from the Airbox to them. I have thought about going topless just have not pulled the trigger on it yet.
 

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Love to know how you guys plan to tune it with such an inconsistent variances in KPA. Head wind and tail wind huge required differences in the calibration needed. This is assuming any meaningful amount of ram can be achieved.
Ron
 

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"Grab your ankles"
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Personally I would like to try to make the vents functional. run some duct work from the Airbox to them. I have thought about going topless just have not pulled the trigger on it yet.
I simply removed the pieces of plastic that are bolted over top of the screens on my Muscle. I can't say for certain that it did much, but opening up the airbox and getting more cold, dense oxygen to the intake can't hurt.
 

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Engines love cool dense air -

Ron at the end of the day I don't think there will be much of an actual pressure increase in the airbox unless someone actually gets the scoop up in clean air up above the handlebars, (that would be pretty crazy) and even then only at higher speeds - and I can't imagine doing 135 Mph with the scoop sticking up there or in the rain so it's more of a city show-off thing. I think the ideal scoop is just a way to get a consistent supply of cooler, denser ambient air in the airbox away from the hot engine - unlike running topless or with a bunch of holes drilled in the lower air box lid like with the S/E cam kit. Do you know what the max limit of the stock ECU is for barometric pressure ? A gauge installed in the airbox of any intended scoop system could probably be a good indicator of any actual pressure increase that may be beyond the ECU's ability to compensate for it. I doubt it would be out of range but the engine would certainly run better with cooler, denser air charge being fed to it, even if not slightly pressurized. Probably equal to or better than the maybe 1 Hp increase of velocity stacks only like some here see on dyno runs- I moved all my wiring and obstructions away from the bellmouth inlet on my airbox and installed vented C/F sidecovers and I believe it helped - can't hurt. Vented Muscle covers would be even better. :blahblah: :D
 

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Ron at the end of the day I don't think there will be much of an actual pressure increase in the airbox unless someone actually gets the scoop up in clean air up above the handlebars, (that would be pretty crazy) and even then only at higher speeds - and I can't imagine doing 135 Mph with the scoop sticking up there or in the rain so it's more of a city show-off thing. I think the ideal scoop is just a way to get a consistent supply of cooler, denser ambient air in the airbox away from the hot engine - unlike running topless or with a bunch of holes drilled in the lower air box lid like with the S/E cam kit. Do you know what the max limit of the stock ECU is for barometric pressure ? A gauge installed in the airbox of any intended scoop system could probably be a good indicator of any actual pressure increase that may be beyond the ECU's ability to compensate for it. I doubt it would be out of range but the engine would certainly run better with cooler, denser air charge being fed to it, even if not slightly pressurized. Probably equal to or better than the maybe 1 Hp increase of velocity stacks only like some here see on dyno runs- I moved all my wiring and obstructions away from the bellmouth inlet on my airbox and installed vented C/F sidecovers and I believe it helped - can't hurt. Vented Muscle covers would be even better. :blahblah: :D
1 BAR/atmospheric pressure is the limit of the OEM ECU (assuming you don't use a 2 bar MAP sensor and scale accordingly).

At any rate, I have posted a while back that short of very high speeds (I want to say it was >125 MPH) the effect is negligible. I know flybigjet posted a Gortex like material (lets air pass, not water) to put behind the Muscle screens if you choose to remove the plastic covers, however other than "feel good" I don't see this doing anything at all of significance.
 

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freudie so yea, that's good info -where is the 1 BAR limit actually being sensed at - above or below the throttle plate ? 1 BAR is actually like .2 PSI less than standard atmospheric pressure at sea level so I'm thinking if you were lucky enough to have even slight positive pressure in the airbox it's just the delivery of cool dense air to the throttle plate - beneath it will still be a lower pressure until the throttle plate is open enough to no longer hold a vacuum - then the air being delivered from the scoop vs the air being consumed would be the only way to get above BAR and like you I think that is unlikely, but just the cooler denser air would make the engine run better kind of like a King Air Turboprop with " Pitot Cowlings " which packs ram air into the engine compressor reducing losses making it work to have to suck it in. Poor mans supercharger, really just optimizing a N/A engine. I had a Toyota with an air dam, two Mikuni Carbs enclosed in a see thru airbox fed by tubing to the air dam and it made quite an improvement to get cooler air from in front of the hot radiator. I think the ECU can handle it but where is it sensing the baro pressure ? Thx. :blahblah: :D
 

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freudie so yea, that's good info -where is the 1 BAR limit actually being sensed at - above or below the throttle plate ? 1 BAR is actually like .2 PSI less than standard atmospheric pressure at sea level so I'm thinking if you were lucky enough to have even slight positive pressure in the airbox it's just the delivery of cool dense air to the throttle plate - beneath it will still be a lower pressure until the throttle plate is open enough to no longer hold a vacuum - then the air being delivered from the scoop vs the air being consumed would be the only way to get above BAR and like you I think that is unlikely, but just the cooler denser air would make the engine run better kind of like a King Air Turboprop with " Pitot Cowlings " which packs ram air into the engine compressor reducing losses making it work to have to suck it in. Poor mans supercharger, really just optimizing a N/A engine. I had a Toyota with an air dam, two Mikuni Carbs enclosed in a see thru airbox fed by tubing to the air dam and it made quite an improvement to get cooler air from in front of the hot radiator. I think the ECU can handle it but where is it sensing the baro pressure ? Thx. :blahblah: :D
The MAP sensor is in the throttle body (well bolted into it). So below the blades (which makes sense as you only care what is going into the cylinders, pressure that is).

As for colder air...ehhhh. My bike has been "topless" forever and the air box cover is anything but sealed on these bikes (read I suspect lots of fresh air enters the box just fine especially when topless).

Your airplane analogy is ok except you are dealing with much greater air pressure (due to greater speeds of course while flying) to have an appreciable difference. On this bike? No way. If you want to see an example of ram air that does something go look at the old Vance and Hines drag V-rod pictures (which is essentially not a vrod especially the engine...but hey marketing). That sucker was huge (and stuck out the side).
 

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The MAP sensor is actually in the back of the front head and comes of a tract tied into the front head intake channel. It's not on the throttle body.

Sent from my Moto Z (2) using Tapatalk
 

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freudie1 yea I think it's time to shed the thought of Ram air (with a pressure rise) and think of it more as a cold air intake which supplies the airbox with cooler air from somewhere in the frontal area of the bike. That side scoop on the V&H race bikes was perfect and I'm sure it helped especially at the top end of the 1/4 where speeds are close to 200 Mph.

elgavilan I checked my parts book and yes, I see it there - in any case I don't think it will ever see above 1 bar since it's below the throttle blade so I don't see any issue with the ECU handling fueling - if anything with extra cool air coming in the IAT may see a drop when running down the road as compared to sitting still with a topless box and the MAP may see a slightly higher pressure ( less vacuum ) but probably within the range of the sensor.
 

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freudie1 yea I think it's time to shed the thought of Ram air (with a pressure rise) and think of it more as a cold air intake which supplies the airbox with cooler air from somewhere in the frontal area of the bike. That side scoop on the V&H race bikes was perfect and I'm sure it helped especially at the top end of the 1/4 where speeds are close to 200 Mph.

elgavilan I checked my parts book and yes, I see it there - in any case I don't think it will ever see above 1 bar since it's below the throttle blade so I don't see any issue with the ECU handling fueling - if anything with extra cool air coming in the IAT may see a drop when running down the road as compared to sitting still with a topless box and the MAP may see a slightly higher pressure ( less vacuum ) but probably within the range of the sensor.
Any IAT temp drop will just richen the fueling possibly balancing out the cooler intake charge if rammed slightly. In reality, my view is the whole concept of ram airing these bikes is an exercise in futility. Streamlining the bike would have more noticeable effects with perceived increase in power. That would screw the looks up though.
Ron
 

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Cool Air Rules

Here's an interesting you tube cold air intake video - www.youtube.com/watch?v=Hiod1c2Py70

It's all about dropping IAT - increasing the O2 in the intake air charge and being able to allow the ECU to add fuel for that lower temp air charge which will result in more power, a greater buffer to detonation and a higher VE. On a 110 Hp Revo engine even 10 degree or a 3.3 % Improvement would be 3.63 Hp - about the same Hp increase a $ 1200 Akropovic exhaust system gives. That's why our bikes run so much better in the fall with lower ambient air temps. Think of the hot air rising directly up to an open air filter sitting stopped at a light vs allowing the cooler air from in front of the engine to be fed to it. Summer vs Fall temp wise, once underway the temp difference would not be as great but still probably 10 degrees less. And Ron hey I can still duck my head once underway for those streamlining advantages - :D :blahblah: :D
 

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Here's an interesting you tube cold air intake video - www.youtube.com/watch?v=Hiod1c2Py70

It's all about dropping IAT - increasing the O2 in the intake air charge and being able to allow the ECU to add fuel for that lower temp air charge which will result in more power, a greater buffer to detonation and a higher VE. On a 110 Hp Revo engine even 10 degree or a 3.3 % Improvement would be 3.63 Hp - about the same Hp increase a $ 1200 Akropovic exhaust system gives. That's why our bikes run so much better in the fall with lower ambient air temps. Think of the hot air rising directly up to an open air filter sitting stopped at a light vs allowing the cooler air from in front of the engine to be fed to it. Summer vs Fall temp wise, once underway the temp difference would not be as great but still probably 10 degrees less. And Ron hey I can still duck my head once underway for those streamlining advantages - :D :blahblah: :D
On a stock tune I agree with better cold air performance. What I've found is if tuned well at 70* in around 50 and under it starts to show a tad rich with soot starting to show on the pipe ends. Me, I've always felt the IAT in this Delphi has too much authority or just don't quite keep the afr in balance per temp. The other issue with the Revolution is the thermostat sucks the big one. If the bike is tuned to ambient temps with coolant temps running in the 185-195, once you get down in the 50* and less the thermostat reaches minimum temp opening which is generally in the 176-178 area. This lower coolant temp richens the mixture again being run at below the tuned temp of normal summer ambient. Not like a cars thermostat where it holds very close to one temp. Revolution T stat has the temps all over the place in operating conditions. It does hold the minimum temp quite well but past 212 there is no t stat effect to be had so technically the stats range is 178 or the basic 180 initial opening to full opening of 212. So, between the two, mixture richens to below what would be desirable for peak performance. Just my observations on my tune and how it behaves during the riding season here in Ontario. Rarely is it ever in total sync between coolant and IAT. For me, it seems 185-195* coolant temp and IAT of 80* for that to be as close to 100% as possible. All based on the original conditions of when the calibration is tuned.
Then again, I've been accused of being OCD, so take it for what it's worth.
Ron
 

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That's great information there Ron - makes perfect sense so yea, so that's probably why a while back that guy posted here that he couldn't get his bike to 130 Mph at 30 something ! degrees ambient air temp basically due to being out of the range of proper fuel mixture control of the ECU and going rich. I suggested that once it warmed up outside it would go full speed again and it did. ( What a wild man - I can't imagine trying to go that fast in that cold a temp ) In any event does anyone make a better T stat for the REVO ? ? I just added that to my final parts list for my engine build - Thanks !
 
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