How can you hook up a tach on a motor that has no spark? Where can you get one? Can you hook it up to the tach already in the car?
Yes, you mount a sensor (optical?) to the motor. I am not sure if it works with a standard tach or not.
your motor controller might have an output for that (it should). also, I know with my 2k3 cavalier, the tach requires a double signal. I’m not sure if the saturns are similar or not.
Hey there, I looked at EVSource’s page and they what looks like a pretty cool speed sensor.
Of course, it hooks up to a Zilla controller and is recommended w/ an Advanced DC Motor. Does this help at all? I know that tachs are replaced by a Amperage meter, but it is speed we are concerned w/ correct?
The other cool thing that they sell is a pedal assemblythat they claim to be able to bypass a potbox. Again, this is for use w/ the Zilla controller (I believe that is the only one w/ a Hairball 
) I guess the Zilla is more expensive, but it might make the conversion process easier. Cheers
I gave them a call and it would work with my motor but not the controller. Good try but I am still looking. thanks anyway, Bob
Most automotive tachs derive their signal from the distributor, at the connection to the ignition coil. Some of the electronic fuel injection systems are however a little different. The automotive tachs receive the same number of pulses per revolutions there are cylinders. 8/rev for 8cyl, 4/rev for four and the like. In the distant past when I was building experimental wind generators I would direct drive an auto distributor from my blades or alternator and use it to run an automotive tach to measure rpm. It was crude and cheap, but it did the job. You can do the same thing using industrial tachs that count the teeth on a gear. To run the tach on the dash I might consider liberating the reluctor, coil and magnet assembly out of the distributor from the converted car and adapting it to your motor shaft. This should be relativly easy, you might even be able to use the original wiring harness.
mike
I finally chraged the batteries up and took it for a spin with my brother in law. What fun it was, Quiet and fast! Not as fast as I thought it would be but comperable to a gas engine if not faster. When I got home I checked the charge on the batteries and got a half charge. The brakes feel like manual brakes to me maybe the booster isn’t working right. I made a few stops and showed a couple of people the car and got mixed reactions. I got called a genus “that was nice of her”. But all in all it was good comments on the car. I still have to install the heater this fall and once the batteries are broke in I’ll be putting in a regeneratation circut. The car still needs a allignment, I’ll see if I can get in tomorrow.
Bob
You did not mention how many miles you got on your half charge.
I assume you meant quick when you said fast. Did you see if it would do 70mph(or how fast).
I had a thought on regeneration. Do you (should you) hook the brake lights in? If so how? I have seen a couple of setups that had a “secondary shifter” (sort of hand brake) that adjusted the regeneration. Some have said that regeneration set to max stopped the car faster than brakes(at speed).
How big was your vacuum reserver? I think you want a gallon at least, unless you have a big pump. I think on saturns the clutch runs off the vacuum too.
Congratulations, you are at least six months ahead of me (if I am lucky).
Thanks
Lazlow
Edit: Sorry Bob, I missed the 25 miles. Doh.
Bob
Here is the type of tach sensor I was talking about:
http://www.evparts.com/shopping/product_details.php?id=444&product_id=1565
Good job, I could only hope to accomplish a similar feat. So, if 25 miles is the half charge, what should you expect, 40 miles or so? That would more than work for me, my commute is only ~35 miles round trip.
I wanted to get back to the Tachometer, Lazlow actually showed you what I found. Someone jerry-rigged their optical sensor, but instead of using magnets to detect rotation, he cut into the flywheel. I like the magnet idea better.
This is his EV Ranger Page
and this is how he set up the Tach
Today I took the car to Gene Butman Ford in Ypsilanti and my cuz took it for a spin. He is a mechanic there, it got his seal of approval!!! All the other mechanics gathered around and asked questions and thier nods too. On my way back home the batteries took a turn to low voltage, I had to pull over to the side several times to get back home. :eek: :eek: but I made it!!! I was about 4 miles out. I put it on the charger as soon as I got home. The KTA charger is still in the shop waiting for a GFCI. The mileage I got was 11 miles today. Plus the 25 yesterday, so driving the way I wanted to I went 32 miles on the freeway and around town and 4 miles limping back home. You have to understand it will take 50 cycles to break in the batteries, and the correct charger will make a difference too. Even though the mileage is dissapointing the car is very quiet and it is cool and fun to drive.
I found out how the Saturn works after a little digging on the wiring diagrams. The tach gets it’s signal from the ignition circut, so me and my mechanic came up with a simple idea that I am going to try. The abs pickups go off a signal too. I have a place on the back of the transmission that the clutch hooked to. I’ll make a bracket for the abs module to bolt to and see if I need one signal or four per revolution of the motor turning. it may take some time to make it work, as I have to pull the board to get to this area.
:rolleyes: I found out how the Saturn works after a little digging on the wiring diagrams. The tach gets it’s signal from the ignition circut, so me and my mechanic came up with a simple idea that I am going to try. The abs pickups go off a signal too. I have a place on the back of the transmission that the clutch hooked to. I’ll make a bracket for the abs module to bolt to and see if I need one signal or four per revolution of the motor turning. it may take some time to make it work, as I have to pull the board to get to this area.