aright i was thinking on going and buying one of thoes 80MM 150 CFM computer fans and mounting it in the airbox snorkle. How do you guzs think this setup will work? I know the computer fans are durable and can even run underwater and getting air forced into the airfilter might help. Also another problem would be what kind of jets sizes would you use? any thoughts?

 

At 7000 RPM your fan will be over an 8 fold RESTRICTION!!!
Go have fun and ride your quad before you blow it up.

 

lol, now how did you caculate this buddy? 8 fold i dont think so it will keep spining faster the more the air sucks and will even help give more air. any how i dont think it will hold up too great and am not thinking im goint to do it.

 

It will do more bad than good, no doubt. Take the snorkle off, that will do you more good than adding a fan...

 

I had a dirtbike that could rip a hole thru a piece of paper when you crack the throttle....I don't think your fan will do all that[img]i/expressions/face-icon-small-happy.gif[/img]

 

A 12 volt fan will in no way compare to the amount of air sucked into a carb muchless add any air to it.


Mikuni Website

The stock Harley CV40 carburetor flows about 185 CFM (cubic feet per minute) when flow is measured at a pressure difference of 12 inches of water. All the Mikuni HSR series flow considerably more:

Stock Harley: 185 CFM
Mikuni HSR42: 213 CFM
Mikuni HSR45: 237 CFM
Mikuni HSR48: 270 CFM

 

Were talking a 150 CFM fan. I would think that the air sucking will speed the fan up even more and creat even more suction. I have tested it with a shop vac and when the power to the fan is off it will spinn at about 2500 RPM and when i put power to the fan it will spin at about 6000 RPM. The faster the fan spin the more air it pushes. I would think it would be normal flow with power off and when you turn it on it will help air flow consideralby. I dont know, Its hard to see it being restrictive at the least. Another ideal How about trying to creat a ram air with PVC so the air coming from the frount of the quad will be pushed into the airbox. This would flow much more and would eliminate delicate electronics.

 

Problem with your thinking is that when the air is turning the fan by itself (i.e. no power on the fan, turning 2500rpm) then that is consuming air velocity, i.e. restricting. More air being sucked through the fan will certainly speed it up, but if you took the fan out of the equation .. all that air could flow unimpeded. If the fan is not drawing air in and forcing it out by it's own power, then it's doing nothing other than restricting flow. If air flowing into the fan is causing it to speed up, that means that the normal air flow is already faster than the fan and hence the fan is restricting the flow.

 

Ya iv talked my self out of the fan ideal but i am leaning toward the ram air ideal were I could take a pvc pipe and stick one end it to the airbox and other end in the front of the quad and make a scoup at the frount below the radiator. This way it will be forceing more air in the faster the quad moves. How about it guzs?

 

certainly more credible than the cpu fan, however .. consider the conditions you ride in .. if you ride in a lot of dust, all of that's going into your filter .. can become very maintenance intensive .. not sure either if the gains would be realized during normal riding since, generally, quads don't go fast enough to create a lot of forced-air velocity ...