Request - crank timing pulley measurement

[adampecush]

Could somebody with a crank timing pulley that is not in their car and a reasonably accurate set of vernier calipers measure the OD of the front pulley outer/front flange? I'm looking to fab a weld-on crank trigger wheel and I don't want to deal with the downtime associated with disassembling the front end of my motor just to take the measurement. If possible, could you measure the flange thickness too? Much appreciated.

To give my request some context, I'm referring to the bottom left pulley in this photo:

 

[NashMan]

Did ya ever get one because I plan to do this as well because my cps will no longer fit

 

[adampecush]

yes, I did. I'll update the thread in the next few days.

 

[NashMan]

can ya make one for me

 

[adampecush]

12 tooth ok? I'm going to make one for Enraged/Toby as well. I'll likely do a half-dozen or more and sell them off.

For what it's worth, here are the measurements:
53.60 mm pulley od (once existing ring is removed)
‎2 mm thickness
65.0 mm outside diameter of ring (and trigger wheel, will go bigger if space allows)

 

[NashMan]

12 should be ok but more teeth the better


really depends how clear ya want it and what ems ya run


how many teeth are in the cps ????


do you plan to run 12 minus 1

 

[adampecush]

Cps has 24 teeth, and rotates at half the speed of the crank, which is essentially 12 teeth on the crank. Going with 12 teeth and none missing will mimic the wheel in the cps, just with a more stable signal as there is no gear lash or belt slop. By the way, pre-vvti 2jz uses 12 teeth and a cam signal - this will be nearly identical aside from the fact that I'm going to keep the CPS for the cam signal (for now).

I'm also running the AEM V1...

 

[hvyman]

It's possible to run 2jz Ecu on 7m. My friend did it while back.

Could always weld a couple teeth on the exhaust cam and then figure out some sort of pick up and ditch the cps.

 

[NashMan]

I would never weld to my stage 3 trd cams i thing some one would hurt me

 

[Enraged]

if you can't use the CPS, best bet is probably a steel pin in the cam gear like NegativeGeForce did: http://www.supramania.com/forums/showthread.php?183939-Ridiculous-1000HP-7M-Street-MK3-Build/page33

 

[limbodk]

View attachment timing gear rev3.pdfView attachment timing gear rev3.zip

There is one that I had made, its a copy of a 36-2 wheel from a 1G-FE out of an altezza which uses the same Toyota pickup as the 2JGE and a bunch of other VVTI engines.

Had it cut from 3mm steel and it was a tight fit in place of the Toyota timing belt guide welded it on for good measure. Will grab a picture of the gear tonight. My set up is still not completed so not sure if it will work or not.

What pick up are you going to use as there is sweet f all room between the harmonic balancer and the front timing cover?

 

[adampecush]

The plan is to use a honeywell 3024 vr sensor mounted to the exhaust side of the lower timing cover, identical to what negativegeforce did in his build thread.

Did you have your gear water jet, laser cut, or machined?

 

[emericaskater285]

if you can't use the CPS, best bet is probably a steel pin in the cam gear like NegativeGeForce did: http://www.supramania.com/forums/showthread.php?183939-Ridiculous-1000HP-7M-Street-MK3-Build/page33

It is actually a magnet. both him and I are running similar setups. I got my trigger wheel from him and the rear lower timing cover predrilled and tapped for the crank hall sensor. I had to do a few modifications to make that setup work. I also wanted my cam pickup sensor to be hidden so I put it behind the cam gear in the valley of the head, and made a passthrough bung to pickup the magnet on the rear of the cam gear. I am happy with how hidden the setup is. I haven't had a chance to fire it up yet I am thinking Ill try to get the first start on the new ecu setup this next week.

I know last time I seen him talk about the trigger wheel he was going to switch it to a 12 tooth crank wheel similar to the 2j's I am not positive why. I am hoping my setup will work with success, or Ill probably end up making a trigger wheel and bracket for a hall sensor and just mounting it off the crank pulley instead.

Also there isn't much room at all behind that crank pulley to mount a hall sensor. I had to modify the body on my sensor to make it work with the crank pulley as it was hitting before, and it already is a very narrow sensor.

I bench tested it while it was on the engine stand and it looked to pickup the teeth perfectly. Ill hopefully update with some positive news and maybe get you guys pics in the next week.

 

[emericaskater285]

The plan is to use a honeywell 3024 vr sensor mounted to the exhaust side of the lower timing cover, identical to what negativegeforce did in his build thread.

Did you have your gear water jet, laser cut, or machined?

Just from first look of that sensor im guessing it is going to be a bit too large. also for a VR sensor you want a sine wave output so you will need to have the teeth be more of a triangle rather than a square, the square tooth wheels are for hall sensors and square wave signals.

EDIT: I guess you might already have that down, I didn't see any pics or info on if you are using square teeth or not.

I wouldn't worry about upgrading if sticking with a VR sensor. I upgraded to go to a hall sensor mainly along with me wanting to get rid of the CPS and clean up the bay a little bit. I also wanted resolution out of the setup.

 

[adampecush]

I'm going to be designing my wheel to mimic the 2JZ 12-tooth wheel as used on the pre-vvti motors (which used a VR sensor IIRC). As I'm on the AEM V1, I didn't want to modify the board to use a hall sensor. Looking at all of Honeywell's options, this sensor seemed to fit the bill the best regarding signal resolution down to cranking speeds.

Regarding the sensor itself, technical documentation states that I need to match the tooth length to the pole piece length - the sensor I'm using is a chisel-type pole piece (long dimension parallel to wheel) , so when I have it in hand, I'll match the tooth length with the pole piece length and I should be good to go.

 

[NashMan]

I think my ecu only likes halls not sure I may have to look this up

i would just make batches of both

 

[adampecush]

First crack at the wheel.

 

[limbodk]

I agree that the best layout of the trigger wheel for a VR sensor should have ramped teeth, however Toyota didn't seem to worry about it enough so that's why I am not worrying either.



The left hand gear is the factory Toyota part, the right hand one is the laser cut gear I added to the 7m timing gear. The square tooth is the same size as the magnet in the end of the sensor as far as I can tell.



This shows my prototype cover with the 1G-FE VR pick up mounted, it is extremely tight to the harmonic balancer and would be the absolute largest sensor possible at 18mm diameter, even this doesn't quite line up with the toothed wheel but seems to still pick up the teeth.



I didn't go with a Hall sensors as they don't like small teeth at high tooth counts, which is why I assume Toyota didn't use a hall sensor. I will probably use a hall for the cam pick up. I went through a huge number of data sheets for aftermarket sensors but most do not like the tooth width we are talking about ~3mm and almost all wanted a 10mm spacing between teeth. I spoke with the maker of my ECU and they specifically said not to use the GT101 Honeywell sensor that seems to be popular, and said to stay with an automotive sensor as they work better in car electrical systems compared with industrial pickups that normally sit on stationary items with out ignition systems right next to them.

Anyway im sure they is more than one way to this, and I am keen to find a sensor Hall or VR that is proven to work well and is smaller than sensor I am planning on using so that I can mount it closer to the balancer and make it line up with to toothed wheel better.

Back to the original question of this whole thread,



By my reading 53.6mm is the OD of the timing gear where the timing belt guide has been pressed on. My toothed wheel needed a few taps with a hammer and it sit solid but each cutting shop will cut slightly differently. I should add that my toothed wheel interferes with the inside of the front timing cover which needed a good dremel to make it fit well.

 

[adampecush]

What would you say the max od you could get out of the wheel? I assumed 76 mm would fit but it clearly doesn't. I'm trying to fit the biggest wheel I can - is 70mm od reasonable?

 

[Enraged]

thanks limbodk for posting all this info.

Is that sensor compatible/comparable to the stock VR sensor? I don't know enough about them, what would I be looking for in terms of sensor specs? Curious if it would work with the AEM v1

I searched that sensor, so thats from an IS200 (90919-05023)? I browsed around and it looks pretty cheap (~$100). Toyota used similar sensors in Corollas too I think. It would be nice to use an OEM Toyota sensor if possible, especially for ease of replacement.