dyno

[Kamuto]

I have one question for dyno owners, I made a dyno for myself, everything is ok, problem is rpm input from an engine, I am calculating it from the rollers, but I would like to have one from engine, now it's inductive one and it's very noisy, maybe someone have schematics for something who can give me 0-5v signal for dyno controller?

[Erikk]

On the land-and-sea dynos, you can just attach an adapter for an injector connector (like this one LINK TO VEMS-SHOP ) .
I guess they are using an opto-coupler (to insulate it from the car´s electronics) and feeding it to a frequency/counter/whatever input.

Maybe that can be an option, or do you need to use an analog input ?

[gunni]

Are you using a sensor that is not being used by the ecu?

If so you can use one of these.
https://shop.vems.hu/catalog/hall-p-162.html?osCsid=121db11ce529dc99fd3a9288caa3ef35

An opto-coupler on a ignition trigger (if you have internally powered coils) would also work perfectly.

[Kamuto]

On the land-and-sea dynos, you can just attach an adapter for an injector connector (like this one LINK TO VEMS-SHOP ) .
I guess they are using an opto-coupler (to insulate it from the car´s electronics) and feeding it to a frequency/counter/whatever input.

Maybe that can be an option, or do you need to use an analog input ?

do you know circuit for that injector pickup? btw would it work with pwm? and most important how to make sure circuit wont affect injector work
no its a special rpm input as I know, I heard about that injector rpm pickup but didn't knew who was the manufacturer, now inside dyno box there is a 555 timer IC for inductive rpm pickup, and works bad

[Kamuto]

Are you using a sensor that is not being used by the ecu?

If so you can use one of these.
https://shop.vems.hu/catalog/hall-p-162.html?osCsid=121db11ce529dc99fd3a9288caa3ef35

An opto-coupler on a ignition trigger (if you have internally powered coils) would also work perfectly.

sensor used not by ecu, how I must to feed the lm1815? ignition wire from inductive clamp? of 12v cable?

[fphil]

 or a voltage divider followed by a diode from any coil wire would give a usable signal, I feed the tach of the car this way

[gunni]

Are you using a sensor that is not being used by the ecu?

If so you can use one of these.
https://shop.vems.hu/catalog/hall-p-162.html?osCsid=121db11ce529dc99fd3a9288caa3ef35

An opto-coupler on a ignition trigger (if you have internally powered coils) would also work perfectly.

sensor used not by ecu, how I must to feed the lm1815? ignition wire from inductive clamp? of 12v cable?

If you use an inductive sensor on the crank for instance then you simply wire the positive into the VR input on that hall converter, negative side goes to the GND point.
On the other side you will have 5v, GND and signal back to ECU or your dyno for instance.

An inductive sensor clamp much like a for a timing light might work, but they are bad at high rpm.

Ideally you can piggyback of a ignition signal if it´s 0-5v. Or filter a injection signal so that it´s 0-12v.
An opto coupler might be able to help in that respect so that there is no connection between the engine side and your dyno.
Just make sure it can handle the flyback voltage if you connect it directly.

[Kamuto]

ok, thanks for the help, I'll try it when finish porshe  not so much left
btw, pic of dyno rear axle front one not finished yet