Hardcore electronics guys - Gear tooth sensor question

[turbostang]

I'm finally getting around to doing the megasquirt for my car and I've come across some stuff that's foriegn to me - mainly the ignition circuit. FWIW, it's going to be a full sequential, 16 injector, LS2 coil driven setup.

Now, the trick is using OEM type parts to build it - which is where I'm semi-stumped. I'm planning on using a gear tooth sensor setup like what's shown in this link about 1/4 of the way down: http://www.msextra.com/doc/ms3/ignition.html I also plan on using the exact honeywell sensor shown.

The problem, or may not even be a problem is that the technical drawing on the sensor shows the trigger wheel spec to be a bit different than what I have to use - in other words, my trigger wheel is bigger than what the drawing says is 'max' size or 'target' size. I don't think it would matter, but I'm open for ideas..

drawing - http://sccatalog.honeywell.com/pdbdo...s/1gt101dc.pdf

My wheel is about 6-6.5" for the crankshaft 36 teeth, one missing (equidistant), aka 36-1 and the distributor wheel would be 2-3" with only one tooth.

[Grape]

larger will help, we have issues with some motec stuff on the motorcycles because the wheels are too small so we don't get enough surface speed to get the box to see a signal at starter rpm.

[R3_82GT]

I built a 8-1 wheel for that same Honeywell sensor that was a lot smaller and it worked fine (we were using it to measure the rotation angle of a shaft). Bigger should be fine also. The size they show is kind of "typical" to give some electrical characteristics. I have a brand new CSS304 wheel (Ford calls it a interruptor) that is 36-1 from Napa I used for some experiments if you want it.

[turbostang]

I built a 8-1 wheel for that same Honeywell sensor that was a lot smaller and it worked fine (we were using it to measure the rotation angle of a shaft). Bigger should be fine also. The size they show is kind of "typical" to give some electrical characteristics. I have a brand new CSS304 wheel (Ford calls it a interruptor) that is 36-1 from Napa I used for some experiments if you want it.

Interesting. I'll have to look that wheel up and see the specs on it. I'm assuming it's a press-on type that goes on the back of the pulley?

[greenbullitt]

https://napaonline.com/Catalog/Result.aspx?Ntt=css304&Ntk=Keyword&Nty=1&Dn=0&D=css304&Dk=1&Dp=3&N=0

[JETFAST]

as long as you get the mag to sync, it doesn't matter a whole lot. just needs to se the edge to generate the rising and falling edge of the wave signal.

[R3_82GT]

Yes, the link to the one Greenbullit posted is the one I have that you can have if you want it - I'm in SW Fort Worth. It's new, I just used it for a little testing on a motor shaft before we cut our own. I think I have some more app notes on the that Honeywell sensor - I'll look. Or if you want some dimensions, I'll measure it for you. I know you're a machinist , but that wheel would be a pain to cut if you can use a pre-made one.

[turbostang]

Yeah, if you can - post up those specs, or PM them to me - either way.

I don't think that wheel will work for me regardless. If it did, it would have to be bored - which is not a problem, but I think I'm going to have a custom laser cut wheel made. I bought the one from DIYAutotune and it has slots for bolt holes and a small pilot hole. If I bore it to the right dimension, it will cut into the slots which will SUCK to machine. I'll most likely end up laser cutting it like I said and having multiple bolt patters done - so the sensor phasing will be easier.

Thanks for the help!

[stevo]

IIRC, the trigger wheel from the EDIS Ford Escort was about 5" diameter and was press-fit on the balancer. I have one somewhere, if I find it I'll measure it. Not sure it that size would help you though.

Stevo

[turbostang]

IIRC, the trigger wheel from the EDIS Ford Escort was about 5" diameter and was press-fit on the balancer. I have one somewhere, if I find it I'll measure it. Not sure it that size would help you though.

Stevo

I think it's closer to 6", I actually have the explorer version at home that I can't use. It's gonna have to be a billet type balancer (it's on my Dart 331) that'll go 9,000 or so.

Megasquirt actually even specs tooth thickness (which is a lot less than the Explorer piece - but it may be machinable). I was just trying to make use of OE type setups, which could go by the wayside because of the need to accurately locate the pickup WITH some adjustability.

[R3_82GT]

The one I have has a bore of 1.230, and outer diameter of 4.965". The keyway is .190.