Megasquirt Support Forum (MSEXTRA)

Hi, does this crank trigger wheel is supported :




Here is the cam trigger arm :



Info on the engine :

Toyota 3SGTE, gen 4, 2.0L, 4 cyl., 4 COP (4 wires so I assume they are with built-in ignitior style)

The crank trigger wheel look like a 32 teeth with a large solid tooth. Each tooth is 10°, so, if I cut in the large solid tooth, I can get a 36 teeth wheel.
The cam trigger arm is simply a steel arm bolted on the intake camshaft. Both cam and crank sensor are VR sensors.

For now, this engine is running with a Ford EDIS4 module + coil + 36-1 crank trigger wheel and VR sensor. But, I feel more experienced with MS and I would like to go sequential COP with all the OEM crank/cam/COP system.

I will be able to get some timing info about the crank trigger wheel and cam trigger arm (position vs engine TDC) in a week or two.

Let me know!

Sam

That wheel would be a 32-2 wheel with a single tooth second trigger this should work.

OK, thanks for the answer. For now, I'll do my homework and I'll read all the MS2Extra manual about 4 wires COP, 2nd trigger input and tacho output.

Thanks for the fast answer!

Sam

turbo355 wrote:That wheel would be a 32-2 wheel with a single tooth second trigger this should work.

Or is it a 36-4 ?

Presently 32 teeth (e.g. 32 non missing or 32-2 etc.) aren't supported as they don't divide nicely into 360, giving 11.25 deg. The code is only to one decimal place.

I had planned to work around this by setting alternate teeth to 11.2 and 11.3 to handle the 32 tooth situation as I believe that some Harleys use a wheel like this. I haven't done this yet.

James

jsmcortina wrote:

turbo355 wrote:That wheel would be a 32-2 wheel with a single tooth second trigger this should work.

Or is it a 36-4 ?

Presently 32 teeth (e.g. 32 non missing or 32-2 etc.) aren't supported as they don't divide nicely into 360, giving 11.25 deg. The code is only to one decimal place.

I had planned to work around this by setting alternate teeth to 11.2 and 11.3 to handle the 32 tooth situation as I believe that some Harleys use a wheel like this. I haven't done this yet.

James

I think your right James, i looked more closely and it does indeed look like 4 teeth are missing .

I assumed 32-2 would work , i didnt think about it not dividing correctly into 360.

It must be a 36-X trigger wheel because there is 10° between each tooth (it is verified). So a 36-4 trigger seems good. I was just unsure about the fact that the 4 missing teeth are in fact one large solid tooth. I will try it as a 36-4 wheel and I'll report back (I will try this new setup this summer).

Thanks

Sam

James would know for sure but i dont think you will have any problems with that wheel.

i have set my 3sgte gen4 to a 36-4, but i still cant get a spark

If it's anything like some of the other toyota crank setups I've seen then it's 36-2...

muythaibxr wrote:If it's anything like some of the other toyota crank setups I've seen then it's 36-2...

thats correct. i have the exact same setup on my toyota 5efe and it runs as a 36-2 wheel

also check this link :

http://msextra.com/forums/viewtopic.php?f=104&t=35169

I agree with the 36-2 trigger wheel setting.

Here's a shot of the crank gear vs the crank angle sensor when the cylinder #1 is at TDC :

http://www.sw20.jp/20/Tech_Articles/BLA ... P/cps2.jpg

Notes :

-the crank rotation is clockwise.
-the arrow on the oil pump housing is indicating the tooth right before the large tooth (which can be considered as a 2 teeth missing gap).

I've calculated the "tooth #1 angle" on my home PC. I'll get that info later today.

BTW, batgirl, would you post or PM your .msq file for me plz. I will do the same for you (mine is not tested yet, was running on EDIS instead of stock COPs).

Thanks

Sam

mine is still not running, i need to set it up to 36-2, but still not sure what angle for BTDC

Hi, I've done a drawing using Solidworks and here's the result :



The block at the bottom is the crank angle sensor.

So, assuming the rotation is clockwise and that this is at TDC on cyl #1, the tooth #1 angle should be set at : 215° (you could try 210° and 220° too).

Please, correct my logic if I'm wrong.

Sam

215 deg

does this mean the trigger angle should be 360-215= 145 ?

http://www.extraefi.co.uk/wheel_fitting.htm

going by this website i think it should be 10x11....110 deg btdc

Thanks for the link.

How did you end up with 110°?

Remember, the rotation is clockwise. The tooth #1 is the first tooth after the first missing tooth (in our case, the tooth #1 is the 2nd missing tooth).

So, after looking at the link you posted, the tooth count should look like this :



And the tooth #1 angle should be 225°BTDC. Again, this pic is when the engine is set at TDC on cyl #1 and the rotation is clockwise.

I would like if someone could verify what I'm saying here.

Sam

That looks to me like you have tooth #1 labeled number 2...

Ken

I though about it too, but I've seen this quote on the extraefi.co.uk website :

http://www.extraefi.co.uk/wheel_fitting.htm

"If using a crank signal with missing teeth, the Tooth Number One will be the first tooth after the gap on a single gap crank (e.g. 36-1) or the second gap on a 2 gap signal (e.g. 60-2, the first tooth will therefore be Tooth #2). "

Picture of the 60-2 trigger wheel from extraefi.co.uk :



So, is this ok now?

Sam

The section you have quoted from is under the heading "MS1-Extra only"

James

You're right, but I was assuming that this was the same between MS1 and MS2. Anyway, this mean that I was correct on my first iteration :



The tooth #1 angle should be 215°.

Sam