3SGTE Harmonic Balancer (Trigger wheel installation)

[Punknoodle]

Hello.

I have a 1990 Toyota Celica GT-Four, turns out the head is a high flowed Gen 1 item, I'm pretty sure the block is a Gen 2. I am installing a new ECU, and my tuner has suggested I install a crank pulley trigger wheel. I have found one for a Gen 2 MR2 on the internet, which looks like a pretty good thing, and I have checked and it looks like the bracket will install on the block no problem, however it looks like the harmonic balancer they attach the trigger wheel to on an MR2 has 2 rib sections on it, however mine only has one. My question is, will I still be able to use my harmonic balancer? In other words, even though my balancer only has 1 rib section on it is it the same thickness as one with 2? If not, will I be able to use an MR2 balancer on my engine, and will one of the rib sections line up with my current alternator belt?

Hopefully this makes sence! Thanks.

[Cuts]

The mr2 balancer has 2 equal diameter sections for belts, the GT-four one has a smaller diameter inner section and a larger diameter outer.

Crank trigger wheel is the go, ditch the dizzy and run coil on plug.

[jonathan yee]

What he said.

However, what ecu are you installing, and are you going to use the dizzy as a cam angle sensor and run individual coils?

[Punknoodle]

I was going to go with a Link G4 Xtreme, however my tuner has suggested I'm probably better off going with a Haltech Platinum Sport 1000. I am checking with Haltech about whether this wheel is suitable, I checked within the tuning software and I see you can select a 60-2 trigger wheel from the settings, so it should be ok. I was going to just install a Haltech hall effect sensor to go with the wheel.

Yes, my tuner said something about utilizing the distributer's trigger for cam angle, and installing LS1 coils. I haven't done any research about this yet, but I'm keen to do it all myself, both to save money and learn more, so any suggestions on where to source them, what I need etc would be greatly appreciated. I'm planning on doing all of the wiring myself and just taking the car there on a transport and getting them to do the initial set up dyno tuning.

Getting back to the balancers - I have drawn this very crude picture to simulate what I'm asking:

In terms of how far the balancers come out from the block, are "a" and "b" the same? This matters, as the bracket has a fixed position for the sensor, and if this is different the wheel will not line up with this position.
The other question, is whether the distance from the outer lip to the inner face - where the 2 threads are for a puller - "c" and "d" are the same, as the wheel comes with a little spacer that bolts to those 2 threads, and then the trigger wheel bolts to that spacer.

The other option is I go with a custom arrangement, but as this is all off the shelf I imagine it was save money and effort...

[Sam_Q]

Your tuner isn't stupid, using the crank based wheel + an additional sensor on the cam lets you run full sequential tuning.

Would it be possible to post a picture of your cam pulley?

I am about to work out what coil-packs fit on the gen 1, unless it was yourself that sent me a message via ebay

[Punknoodle]

Small world, yep that's me! I believe it's just going to be the new crank trigger wheel and for the cam angle sensor he was going to utilize the factory distributer's can trigger - I believe it has a 24 tooth sensor

[Sam_Q]

Using a crank wheel means you only really need an on/off signal to tell the ecu if it's in a compression or exhaust stroke so almost anything will do, sounds like your on the right track. You could do it the other way though, use the factory sensor for crank position and then have an on/off off the crank, basicly just a half moon shape

[Punknoodle]

Apparently the factory sensor doesnt have enough scope, which is why he suggested a crank trigger wheel

[Sam_Q]

Sounds to me like he knows what he is talking about so go with it.

[Punknoodle]

Ok, cool. I'll message you later on re the coils. It's just the balancer comparability I'm wondering about now.

[Punknoodle]

Ok so I've heard back from Scott at Haltech, and he is telling me that a 60-2 trigger wheel isn't recommended, and I'd be better off going with a 12 tooth wheel from another Toyota and grafting it somehow to the crank pulley.

Anyone know of a suitable trigger wheel that I can adapt to my balancer? And anyone know of an engineering shop I can use to make an adapter?

Thanks!

[jonathan yee]

they do crank triger wheels 12 or 60-2 etc, also everything else to remove dizzy etc and many other hi quality products for the 3sgte

COP conversion kit

[thechuckster]

I vaguely remember seeing some 36-1 trigger wheels simply bolted onto the front the pulley (using the holes put there for pulley removal), but a quick search found this:
Rebuilding the 3SGTE - Page 3


and later on in the thread is this interesting pic of a kit for a CAS

[Punknoodle]

Cool, thanks I've sent them an email.

Can I ask what may be a silly question - why exactly is installing a crank sensor a good idea? I've been in contact with a few people and there so many different opinions. A lot of people are saying the factory triggering is fine, my tuner says no. If the cam trigger is a 24 tooth and it gets replaced with a 12 tooth crank trigger then what is the difference? I don't really understand, I just want the tuner to be able to extract the most potential he can!

[thechuckster]

Personally I can't see why you would go back to a 12-tooth wheel from a 24.

(edit: Simply replacing the dizzi-based 24-tooth wheel with a 12-tooth wheel on the crank would be no improvement.)

With the speed of most ECUs, the crank trigger provides rpm data but crank position is determined from the cam sensor data PLUS the crank rpm data. Older ECUs would count trigger pulses and in combination with missing teeth and CAS signal(s) determine crank location. Newer ECU/code designs are about predicting crank location based on RPM, CAS and also current rev rate, current Accel mode, estimated load, etc.

Argument for not using the dizzi-based CAS for crank and cam position is the slop between the sensor (flexible belt, twisting cam, dog-link on dizzi shaft to cam. Also, a dizzi-based CAS is running at half-crank speed so there is some loss in rpm calculation precision.

One thing to point out about the factory dizzi setup is it's basically a 12-1 trigger wheel (it might have a 24 tooth wheel plus two sensors looking at a 1 tooth wheel, but it's running at half speed).