Device for wheel speed checking?
#1
Device for wheel speed checking?
In a nutshell: I want to be able to put new drivers in a slow class regardless of the equipment they have. The easiest way to do this is adjust the EPA of the throttle. But we hire the venue by the half hour and are really short on time at the beginning of the meets, so driving up and down the straight isn't the best option. I figure if I could just free-rev the cars and measure the wheel speed that would be pretty close to what I want. Does any one know of a cheap hand held device I could use to do this job?
#3
In a nutshell: I want to be able to put new drivers in a slow class regardless of the equipment they have. The easiest way to do this is adjust the EPA of the throttle. But we hire the venue by the half hour and are really short on time at the beginning of the meets, so driving up and down the straight isn't the best option. I figure if I could just free-rev the cars and measure the wheel speed that would be pretty close to what I want. Does any one know of a cheap hand held device I could use to do this job?
http://www.rccartips.com/rc-car-dyno-cheap.htm
https://sites.google.com/site/simpledyno/the-dyno
#5
Tech Master
iTrader: (2)
http://www.extech.com/instruments/pr...=21&prodid=252
If budget is a little higher, this would be good....but again, it doesn't test under load....
If budget is a little higher, this would be good....but again, it doesn't test under load....
#8
http://www.extech.com/instruments/pr...=21&prodid=252
If budget is a little higher, this would be good....but again, it doesn't test under load....
If budget is a little higher, this would be good....but again, it doesn't test under load....
It won't test under load, sure. But how much will that really matter in the long run do people think? I mean, after a short time it should be possible to get used to interpreting the reading, and the load isn't going to be too dissimilar between cars. I don't really need accuracy, just precision enough to know that the car will do about the right speed when it's put on track.
#9
Tech Regular
iTrader: (8)
digital tacho
my first thought was same as earlier posted. but try this a bit cheaper.
http://www.jaycar.com.au/productView.asp?ID=QM1448
http://www.jaycar.com.au/productView.asp?ID=QM1448
#11
http://www.extech.com/instruments/pr...=21&prodid=252
If budget is a little higher, this would be good....but again, it doesn't test under load....
If budget is a little higher, this would be good....but again, it doesn't test under load....
But there is a problem. A good battery freshly charged coupled with a good speedo and a nice wiring job will give you a higher reading (no load revs will be higher) than an old tired battery etc. even if both cars have the same FDR.
I used the tacho to check there was no wear in my drivetrain that would cause the wheels to spin at different speeds (worn bearings, belts, etc).
#12
That is exactly what I was going to suggest and I have actually bought the Jaycar version linked in another post above. Resolution is much more than you will ever need, and it's a piece of piss to measure each car.
But there is a problem. A good battery freshly charged coupled with a good speedo and a nice wiring job will give you a higher reading (no load revs will be higher) than an old tired battery etc. even if both cars have the same FDR.
I used the tacho to check there was no wear in my drivetrain that would cause the wheels to spin at different speeds (worn bearings, belts, etc).
But there is a problem. A good battery freshly charged coupled with a good speedo and a nice wiring job will give you a higher reading (no load revs will be higher) than an old tired battery etc. even if both cars have the same FDR.
I used the tacho to check there was no wear in my drivetrain that would cause the wheels to spin at different speeds (worn bearings, belts, etc).
#13
That said, a good speedo is going to deliver and sustain much higher currents than your ordinary el cheapo, so not sure where that leaves you.
#14
I reckon it can be anything, but I think you need to think how much a tolerance you are ready to accept. 10% wouldn't surprise me and that is a lot.
That said, a good speedo is going to deliver and sustain much higher currents than your ordinary el cheapo, so not sure where that leaves you.
That said, a good speedo is going to deliver and sustain much higher currents than your ordinary el cheapo, so not sure where that leaves you.