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If the scoop or collector box is large enough you don't need a lot of speed to have an extremely effective "cold air" intake - Where this goes off the rails is when we start looking at it as a " Ram Air " system. 90% of the time a V Rod in average street use won't go fast enough for Ram rise effect even if the scoop was the size of a breadbox mounted on the front fender - BUT if you're smoothly stuffing cooler ambient air into the airbox instead of hot turbulent air from above the engine getting sucked in there you really don't need to worry about there being no Ram rise because you've already gained a large advantage over stock. If you can get a little Ram rise at higher speeds all the better but the cool air intake is the e ticket. I've got one on my T/Blazer SS using a removed fake vent cover inboard of the rt. headlight that forces air to a Volant Cold Air filter box and also on a 4 Cylinder Toyota Celica using a see thru Lexan Airbox attached to two side draft Mikuni Carbs fed by two hoses to the front air dam. These systems work - I'm building one for the V Rod now.
 

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I am thinking of removing the air box and mounting a Hilborn air scoop directly above the intake horns. This would seem to provide a considerable ram effect at high speed. I don't know anything about the fuel injection system. My question is would this cause the engine to run lean at high speed or can the fuel injection compensate for the extra air? I assume it would need to be reprogrammed for it but how would that be possible since you couldn't simulate the conditions on a dyno?
 

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I am thinking of removing the air box and mounting a Hilborn air scoop directly above the intake horns. This would seem to provide a considerable ram effect at high speed. I don't know anything about the fuel injection system. My question is would this cause the engine to run lean at high speed or can the fuel injection compensate for the extra air? I assume it would need to be reprogrammed for it but how would that be possible since you couldn't simulate the conditions on a dyno?
Yes it will screw the existing tune up and next to impossible to re tune it well. Step away from the bike. See how much trouble I just saved you? LOL
Ron
 

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Ron - Certainly there has to be a way to tune for it, don't you think ? It's really just the detected range of the manifold pressure and the RPM. It's done all the time on boosted engines, and they have no idea how fast the car or motorcycle is going or where the boost is even coming from. My 2 cents is even if you had a lower profile Air Scoop, and Summit Racing has a couple, P/N SUM-G3106-1 or 08-1 are 20" long ( both with inlet butterflies but lets not even go there ) it would have to be 12" higher above the velocity stacks base to get clean ram air without a windshield ( that's on a low handlebar R Model ) and 24" higher with a sport windshield and higher than that with a tall touring windshield to create even a promise of any pressure rise at all that would affect the tune. Even then the pressure rise might be in range of the stock EFI system tuned to full power safe rich to compensate for extra air at high speed. Lets face it guys except for the occasional burst to 130+ Mph most V Rod riding is 80 Mph or less. So let's build it pepper 46 I'd love to see it and V Rods has been always begging for it ! - I'm really surprised no one here has done it even just for a gag. Reminds me of Rat Fink 3 foot high car floor shift levers in the 60's - over the top ! Ron & the rest of these Revo Guru's can figure out how to tune it if there are any tuning problems - hell, it would get a lot of excitement back on this site, and it would look crazy cool ! (y) :D
 

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Ron - Certainly there has to be a way to tune for it, don't you think ? It's really just the detected range of the manifold pressure and the RPM. It's done all the time on boosted engines, and they have no idea how fast the car or motorcycle is going or where the boost is even coming from. My 2 cents is even if you had a lower profile Air Scoop, and Summit Racing has a couple, P/N SUM-G3106-1 or 08-1 are 20" long ( both with inlet butterflies but lets not even go there ) it would have to be 12" higher above the velocity stacks base to get clean ram air without a windshield ( that's on a low handlebar R Model ) and 24" higher with a sport windshield and higher than that with a tall touring windshield to create even a promise of any pressure rise at all that would affect the tune. Even then the pressure rise might be in range of the stock EFI system tuned to full power safe rich to compensate for extra air at high speed. Lets face it guys except for the occasional burst to 130+ Mph most V Rod riding is 80 Mph or less. So let's build it pepper 46 I'd love to see it and V Rods has been always begging for it ! - I'm really surprised no one here has done it even just for a gag. Reminds me of Rat Fink 3 foot high car floor shift levers in the 60's - over the top ! Ron & the rest of these Revo Guru's can figure out how to tune it if there are any tuning problems - hell, it would get a lot of excitement back on this site, and it would look crazy cool ! (y) :D
Thanks SRR, maybe I'll try it as soon as I start working on chopping my Rod. I'm an old, and I do mean old (74) chopper guy and the Rod is the first bike I've had in a long time without customizing it. I think I've finally figured out what to do to it to make it unique and cool with a mix of old school and new. I regularly run it over a hundred on the freeway but not over 130 because it's my daily rider and I don't want to over-stress the motor.
 

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Ron - Certainly there has to be a way to tune for it, don't you think ? It's really just the detected range of the manifold pressure and the RPM. It's done all the time on boosted engines, and they have no idea how fast the car or motorcycle is going or where the boost is even coming from. My 2 cents is even if you had a lower profile Air Scoop, and Summit Racing has a couple, P/N SUM-G3106-1 or 08-1 are 20" long ( both with inlet butterflies but lets not even go there ) it would have to be 12" higher above the velocity stacks base to get clean ram air without a windshield ( that's on a low handlebar R Model ) and 24" higher with a sport windshield and higher than that with a tall touring windshield to create even a promise of any pressure rise at all that would affect the tune. Even then the pressure rise might be in range of the stock EFI system tuned to full power safe rich to compensate for extra air at high speed. Lets face it guys except for the occasional burst to 130+ Mph most V Rod riding is 80 Mph or less. So let's build it pepper 46 I'd love to see it and V Rods has been always begging for it ! - I'm really surprised no one here has done it even just for a gag. Reminds me of Rat Fink 3 foot high car floor shift levers in the 60's - over the top ! Ron & the rest of these Revo Guru's can figure out how to tune it if there are any tuning problems - hell, it would get a lot of excitement back on this site, and it would look crazy cool ! (y) :D
Issue is actually tuning it but in theory should offer some hp gains. Dyno, ain't going to happen. On the road and actual ram conditions, self tuning that way, unless the autobahn is in the back yard you will either get arrested or die.
Ron
 

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Issue is actually tuning it but in theory should offer some hp gains. Dyno, ain't going to happen. On the road and actual ram conditions, self tuning that way, unless the autobahn is in the back yard you will either get arrested or die.
Ron
Well, I live out in the country and it hasn't happened so far LOL
Pepper
 

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At the end of the day I don't think anyone will mount the scoop high enough to really scoop enough air for it to have a ram effect that would affect the engine enough to create the need for a different tune at speed, where it would start going lean, and most guys don't ride that fast anyway. Like Ron said a self tuning system ( with Wide Band O2 sensors ) might compensate if you did mount the scoop in clean air and if you rode that fast but if we're talking a scoop mounted below the handlebar level in dirty air more for the impact of looks than performance I think we can all agree it wont be a tuning problem. I say let's build it just for the audacity of it - a Hot Rodders dream look on a V Rod - I just measured scoop needs to be about 12" long 8" wide and have enough depth to cover the offset on the height of the velocity stacks, plus a guy would have to modify an airbox cover to become a skirt for the scoop so all the hoses, wiring, radiator cap battery etc. would remain covered ( unless you want to let it all be visible ). Lots of fab work but looks like a fun project to do during the down time caused by Oh, I don't know, a worldwide pandemic ?! (y):oops:
 

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As Luck would have it I tripped on a photo of a V Rod with a scoop right here on the site - I couldn't drag it over to this thread but if your curious go to the General Off Topic Area to " Coolest Pic of Bike & Rider " see HD Heathens post # 2822 on page 142 ( the last page of the thread ) - a Silver V Rod with a Silver Scoop - I thought someone would have done it ! Plenty of innovative gear head V Rod owners out there - (y) :D
 

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Looks like it's actually feeding a supercharger. Not quite my vision, especially with the rear struts. Still a cool looking bike. I'm planning on replacing all the stock bodywork with nothing prefab, not even handlebars, which will be a Y shape. Yes, the 13.5 hilborn scoop will be the right size mounted on an oval shaped riser around the velocity stacks with a fabbed aluminum cover for the battery and wiring. Not too hard to fab with aluminum.
 

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I'd like to mount a 21 front wheel like that but with dual discs and a 120 tire, but I don't know what hub would work.
 

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Looks like it's actually feeding a supercharger. Not quite my vision, especially with the rear struts. Still a cool looking bike. I'm planning on replacing all the stock bodywork with nothing prefab, not even handlebars, which will be a Y shape. Yes, the 13.5 hilborn scoop will be the right size mounted on an oval shaped riser around the velocity stacks with a fabbed aluminum cover for the battery and wiring. Not too hard to fab with aluminum.
Holy ugly/ridiculous. Looks like someone raided their old rat rod and threw parts on the v-rod. Even the "machine work" (really loose usage of that term as it looks like sheet metal work) is terrible.

I thought I saw it all.
 

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"Holy ugly/ridiculous. Looks like someone raided their old rat rod and threw parts on the v-rod. Even the "machine work" (really loose usage of that term as it looks like sheet metal work) is terrible.

I thought I saw it all."

Freudie1 that right there is some funny stuff ! But sometimes a guys V Rod blower just bulges up and pops out its ugly head from his airbox cover, only to get topped off with a scoop ! It happens, just imagine if it was 8" higher to get clean air and maybe some ram air effect at about 90 mph you'd have to have guide wires holding it in place !

Pepper46 Nice Knuckle Head project ! My buds got an FXR and an award winning Hardtail Shovel - you just can't beat the " Real Harley's " but I bet you could make a scoop look good on a V Rod so just don't forget about it ! - in the meantime I'm working on a project during this CV19 downtime that will be appreciated here, can't wait to show it to you all - Good Luck, Stay Safe & DON'T get the Flu Crud from Hell ( China ) !
 

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By The Way that's a dedicated 1/4 mile racer, note rear slick & struts, supercharger & scoop, race tach / boost gage / shifter light combo, fwd controls mod to mids and air shifter, etc. I think this is a function over form guy although overall it still looks pretty cool it's a dedicated race bike not a street cruiser/poser.
 
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