I know ive seen one somewhere. its a small s blade fan built into a pvc bullet with stubs hanging off both ends for hose attachment. want to say they use a 2/12 or 3 inch hose.
you guys have any sources or specs? im trying to find a compact way to move a TON of air (pressure and volume) through a hose from a remote location under the dash (this is for a custom fabbed AC project.
You mean something similar to this?
similar, yes. only the ones ive seen sont have the little bracket. where did you find that?
Brake blowers. I'd think any stock car supply website should have listings.
Edit: Like this:
http://www.southwestspeed.com/?sec=view_part&id=1185
I want those on my street car. Just because.
Dusterbd13 wrote:
similar, yes. only the ones ive seen sont have the little bracket. where did you find that?
I just looked up Inline PVC duct fan on google.
Streetwiseguy posted what you probably want. A brake duct blower.
Call it a bilge blower and it's easier to find. I use one in the Targa Miata for a defroster motor. All over Amazon.
http://www.cmwraceparts.com/proddisp.php?pn=LHC7102 is a little cheaper.
I've used it in two cars one for helmet blower and one for brake duct. sticker on it calls it a bilge blower it move alot of air.
Anyone know if they make multi speed versions?
My next question, now that I know what I'm looking at, is just how much air/pressure one of these is capable of. What I'm thinking about is using these, connected to flexible hose, as a remote mount blower for an underdash ac untit. Probably be able to fit two of them if I remove the glovebox.
So, just how much air do these things push?
And most I've seen are rated at less than three amps. Id think a rotary rheostat would make them multispeed.
Are you talking about pressure or volume ?
Often noted as CFM.
Keith Tanner wrote:
Call it a bilge blower and it's easier to find. I use one in the Targa Miata for a defroster motor. All over Amazon.
Threadjack/
Do you have pictures of how you did this?
end threadjack/
I know pressure and volume are related. What I need to do is push air through an evaporator core with enough force that the driver/passenger can feel it well (like a latemodel on high through the dash vents) with enough air as well to reasonably cool the inside of a midsize regular cab truck. I know thisx isn't a perfect solution, but I believe I can cobble an ac only setup for my truck for about 100 bucks.
Would a pair of these, through 3 inch flexible tubing on a run of about 12 inches do this?
Could I step the tubing size down to get air velocity/pressure up and make it work better?
Am I just creating a headache for myself?
I think they would be marginal at best. If you're insistent on using one of these, at least get the squirrel cage version so the noise won't drive you batty.
What would work for sure, though, is a 60's style under dash AC unit.
Or, if it has to be remote mounted, the same seller has this too
RossD
PowerDork
8/1/13 11:50 a.m.
If you can, don't use flexible duct, use anything smooth and rigid. Ducts can be square or rectangular, just transition back to round at the fan. Don't go past 1 unit by 4 units for a size ratio while trying to keep the same free area of the duct connection to the fan (1 unit by 1 unit is better <-square, round is best).
Using smaller ductwork will only increase your pressure drop through the duct and lessen the CFM you get out. You can actually put so much of a restriction that you won't see any flow at the outlet of the ductwork.
Most of the CFMs of those bilge fans are at open conditions; add ductwork on both ends and you'll get less than that. Fans like nice straight ductwork before and afterwards to maximize performance. Think about the fan diameter times 2 or 3 for straight lengths.; So maybe a 8"-12" at each end; that's optimum of course.
Its actually a 60's vintage underdash unit I'm trying to make work. Currently, it has a pair of squirrel fans at the back of the evap. These will not clear the factory heater box no matter what I do. So my thought had been to remote mount the fans to free up room (mounting depth wise). I could probably hard plumb it, but would have to look closer at the options for that. The inlets would have to be a 90 going into the evap housing.
Most 3 inch units claim 150cfm but jump up to the 4 inch and they claim 230cfm.
whenry
HalfDork
8/1/13 3:06 p.m.
Similar units are used to boost the AC systems in Porsche 911. I had been considering adding to the underdash duct but was concerned about noise too. Never seen or heard one run so gotta experiment with it. I would think that rheostat would work also.
Vigo
UltraDork
8/1/13 4:56 p.m.
Anyone know if they make multi speed versions?
You can just hook one to the factory fan motor circuit on a car and use the factory speed controls unless you happened to rip those out for absolutely no good reason. Even cars that didnt come with factory AC came with fan switches and blower resistors for different speeds.