SPAL brushless fan

[Bitsyncmaster]

Interesting.

It would really be nice to know how much air it flows at say 42%. When I get the fan, I can put a air speed indicator pitot tube in front, but I don't know that's a fair comparison. It would measure speed, not volume. Also I would need a controller. What would you charge for one?

If the fan would flow more than a stock fan at 42%, then it might be a benifit. An expensive benifit, but a benifit. Still, to make it work I would need a way to make the top speed be the 42%-57%. (Whether engine or AC) At least to keep stock wiring in the car.

I guess you haven't put a reflector on a blade and measured rpms? Would the 42% be 42% of the rpms? What I mean is, the fan is supposed to spin from 1000 to 4000 rpms. So would 50% be 2500?

I have an optical tach. Little busy today but will find some time to check RPM later. I can send you my controller but it has an adjustment to set fan speed so you would need a way to measure duty cycle at the signal output. Or I could make that adjustment just do a few preset speeds with a software change.

[Bitsyncmaster]

I found my hot wire anemometer. I think I just have to measure the air flow speed and then I enter the diameter of the fans (both OEM and SPAL are close to 10 inch. and that computes CFM. It's still a crude way to compare since you will get different speeds depending on the measurement at mid point of the blades and distance from the blades.

[CFI]

Interesting.

It would really be nice to know how much air it flows at say 42%. When I get the fan, I can put a air speed indicator pitot tube in front, but I don't know that's a fair comparison. It would measure speed, not volume.

Pitot tubes are useless without a static port. An anemometer would be a better choice. But as you mentioned this still wouldn’t provide any meaningful data.

[Bitsyncmaster]

Pitot tubes are useless without a static port. An anemometer would be a better choice. But as you mentioned this still wouldn’t provide any meaningful data.

All these fan tests by us are only meaningful when we compare the same test at the same time to a standard (OEM fan). The only CFM test I would trust is a very large plastic bag, timed how long it takes to fill.

Basically the power the motor uses is the measure of how much air it moves. But as stated earlier our D does not need the power of OEM fans.

The real test is how it performs in the car.

[JBaker4981]

Out of curiosity, DPI's Fans/Fan Shroud system incorporates SPAL fans - are these the same units or comparable? Probably not, but was simply curious.

When I was trying to figure out what was going on with my Fan Circuit last year, I measured the Amperage draw of each SPAL fan and found they were a moderate ~8.7A at full power.

Driver Fan: 8.74a @ 12.90V
Passenger Fan: 8.68a @ 12.87V


Also not to digress, did you ever test the DPI Fans as you did with the Harvey, Toby, and DMCH fans in your tests a few years ago? I was reviewing that thread recently and noticed you passed on it when Josh offered up.

[Bitsyncmaster]

Out of curiosity, DPI's Fans/Fan Shroud system incorporates SPAL fans - are these the same units or comparable? Probably not, but was simply curious.

When I was trying to figure out what was going on with my Fan Circuit last year, I measured the Amperage draw of each SPAL fan and found they were a moderate ~8.7A at full power.

Driver Fan: 8.74a @ 12.90V
Passenger Fan: 8.68a @ 12.87V


Also not to digress, did you ever test the DPI Fans as you did with the Harvey, Toby, and DMCH fans in your tests a few years ago? I was reviewing that thread recently and noticed you passed on it when Josh offered up.

That testing I did was a long time ago. I think only Hervey and Toby were selling fans back then. I had bought Hervey fans about 15 years ago when I first bought my car. They worked fine but later went with Toby fans just because I liked they used the OEM shroud. Toby fans also have been work fine. These SPAL fans could not be used with stock wiring in the D. You would need to run 8 AWG or 6 AWG wire to power two of them. They don't use relays or fan fail circuits. They use a special temperature sender to turn them on and off. But you could wire them to use the otterstat and AC on but then they would only run at full speed (27 amps or more each).

[Helirich]

Out of curiosity, DPI's Fans/Fan Shroud system incorporates SPAL fans - are these the same units or comparable? Probably not, but was simply curious.

When I was trying to figure out what was going on with my Fan Circuit last year, I measured the Amperage draw of each SPAL fan and found they were a moderate ~8.7A at full power.

Driver Fan: 8.74a @ 12.90V
Passenger Fan: 8.68a @ 12.87V


Also not to digress, did you ever test the DPI Fans as you did with the Harvey, Toby, and DMCH fans in your tests a few years ago? I was reviewing that thread recently and noticed you passed on it when Josh offered up.

I didn't realize DI used Spal fans. They are not brushless, but still I consider them to make the best brushed fans also. On their site, they claim 5.4 amps each. Not sure why these numbers seem to be pulled out of a hat, but your numbers are pretty good. After I give up on the brushless fan, I will probably get a set from DI. Two fans and a shroud cost slightly more than half of what I spent on one fan and sensor. I guess I can't take it with me. Lol.

[Bitsyncmaster]

I didn't realize DI used Spal fans. They are not brushless, but still I consider them to make the best brushed fans also. On their site, they claim 5.4 amps each. Not sure why these numbers seem to be pulled out of a hat, but your numbers are pretty good. After I give up on the brushless fan, I will probably get a set from DI. Two fans and a shroud cost slightly more than half of what I spent on one fan and sensor. I guess I can't take it with me. Lol.

+1
SPAL has a pretty extensive tech ref information and seem to be only producing fan products. Their current consumption is measure with open air so mounted to a radiator and condenser is going to draw more current. I would guess the fan blade design is optimized for the full speed of the motor so running a brushless motor at lower speeds may not be more efficient than a brushed motor.

[Helirich]

Pitot tubes are useless without a static port.

This statement is true, but all air speed indicators I know of have static ports. So I'm not sure what your point is. If your saying the placement of the static is important, that's true for a moving vehicle, but for a mounted fan, just place it out of the wind.

I think we can make a fairly accurate cfm calculation pretty easy. I was worried that there would be differnt air speeds at differnt locations on the fan. (Tip vs center) But after bit of thought, all we have to do is run the fan at the end of a duct and the air speed indicator at the other end. (Wind tunnel) I think 3 feet would be enough to average all the flow out.

[DMC-Ron]

+1
SPAL has a pretty extensive tech ref information and seem to be only producing fan products. Their current consumption is measure with open air so mounted to a radiator and condenser is going to draw more current. I would guess the fan blade design is optimized for the full speed of the motor so running a brushless motor at lower speeds may not be more efficient than a brushed motor.

Open air is worst case. Once you add restrictions, the fan ends up moving less air and does less work. It's a little counterintuitive, like putting your hand over the vacuum hose. All things equal, the brushless will be more efficient than a brushed motor but the difference would diminish as speed decreases. ECM motors are becoming increasingly popular for fans and pumps because of their efficiency. I think Toby's fans are brushless.

Ron