ignition question

[boosted to 26psi]

Pretty simple....I know the 7mgte uses a dis system....will it run with the na dizzy in place of the cam sensor.....disregarding codes. Simple enough will it run.

[btwilson86]

If you're talking about using the N/A dizzy as just a position sensor, then yes. It should work just fine with minimal effort, shouldn't throw any DTC's either.

[boosted to 26psi]

Originally Posted by btwilson86

If you're talking about using the N/A dizzy as just a position sensor, then yes. It should work just fine with minimal effort, shouldn't throw any DTC's either.

not entirly. i got a buttload of extra parts...basically finishing someone elses work. and i have the cps but no coils.....so i guess my question is would it run using the dizzy instead of the coils. or would the ecm go apeshit....the motors been swapped to the 7mgte....it was a na auto. so im thinking the na wiring harness is still in the engine bay, just by looks.

guess i should say did these cars come from factory with a dizzy or coil pack

[cre]

I'm sure you're going to have significant issues due to the ECU. Both systems (GTE and GE) are controlled by the ECU. In the GE the ECU gets cam position from the 'dizzy' (the same components that are in the GTE's CPS are in the base of the dizzy for this purpose) and then sends a signal to the igniter when it deems fit (this occurs 6 times per crank revolution). With the GTE it sends 3 signals two times per revolution. You'll need to combine the signals into one (isolating the signals prior to the igniter) and convert to a GE igniter and GE coil. It may be as simple as soldering in a few diodes, running the three signal lines into the GE igniter's one... but I'm willing to bet it's going to be a lot more trouble than that.

Honestly... I wouldn't ever even bother. The only reason a GTE should see a GE's distributor is as a temporary CPS.

I'm confused by your lasts sentence... It sounds like you know and then you don't... The 7M-GTE is a "points-less" system (multi channel igniter, coil packs and basic CPS); It is also a "wasted-spark" setup. The GE uses a "points" aka a basic distributor system.

[boosted to 26psi]

Originally Posted by cre

I'm sure you're going to have significant issues due to the ECU. Both systems (GTE and GE) are controlled by the ECU. In the GE the ECU gets cam position from the 'dizzy' (the same components that are in the GTE's CPS are in the base of the dizzy for this purpose) and then sends a signal to the igniter when it deems fit (this occurs 6 times per crank revolution). With the GTE it sends 3 signals two times per revolution. You'll need to combine the signals into one (isolating the signals prior to the igniter) and convert to a GE igniter and GE coil. It may be as simple as soldering in a few diodes, running the three signal lines into the GE igniter's one... but I'm willing to bet it's going to be a lot more trouble than that.

Honestly... I wouldn't ever even bother. The only reason a GTE should see a GE's distributor is as a temporary CPS.

I'm confused by your lasts sentence... It sounds like you know and then you don't... The 7M-GTE is a "points-less" system (multi channel igniter, coil packs and basic CPS); It is also a "wasted-spark" setup. The GE uses a "points" aka a basic distributor system.

See that's what im kinda getting at. Why would the n/a run a regular ignition system, but the the boosted engine run a dis system. They both basically so the same shit, except the dis run more shit.

[cre]

I'm having some trouble understanding you. Are you actually asking why they would use a direct ignition system on the 7M-GTE? Direct ignition systems run more efficiently, provide better spark and offer a much greater degree of control to the TCCS... But they're expensive so Toyota only offered them with the higher end model... go figure. Sadly, back when this system was built it wasn't refined enough to make a significant "real world" difference sooooo.... How about we stick with the "just for the hell of it" reasoning?

Toyota's always screwed around with the various configurations of the Supra. There were significant differences between GE and GTE in the MKIV too. There were MKIII models which used MAP versus VAFM or KVAFM.... The Supra was always both a testbed and showcase for newer technologies.

I wouldn't consider downgrading the ignition though... aside from losing some small degree of performance and the electronic modifications which will be required you're going to have a very bad time getting the dizzy and plug wires to fit; The intake is in the way.

[boosted to 26psi]

Originally Posted by cre

I'm having some trouble understanding you. Are you actually asking why they would use a direct ignition system on the 7M-GTE? Direct ignition systems run more efficiently, provide better spark and offer a much greater degree of control to the TCCS... But they're expensive so Toyota only offered them with the higher end model... go figure. Sadly, back when this system was built it wasn't refined enough to make a significant "real world" difference sooooo.... How about we stick with the "just for the hell of it" reasoning?

Toyota's always screwed around with the various configurations of the Supra. There were significant differences between GE and GTE in the MKIV too. There were MKIII models which used MAP versus VAFM or KVAFM.... The Supra was always both a testbed and showcase for newer technologies.

I wouldn't consider downgrading the ignition though... aside from losing some small degree of performance and the electronic modifications which will be required you're going to have a very bad time getting the dizzy and plug wires to fit; The intake is in the way.

So where's the best but cheapest place to get a replacement coil....also ia the mass airflow sensor necessary. How to bypass that, what part are interchangeable, how do I tell if I have thw 7m-gte engine harness an ecu.

[btwilson86]

ECU tells you right on it which engine and transmission it's for. I think the easiest way to find out which harness you have is to see how many knock sensor connectors you have on it. 1=GE, 2=GTE.


And the KVAFM is important, don't get rid of it unless you're replacing it with some other air metering device (different AFM, MAF, MAP, etc).

[cre]

Oh for the love of all that is considered progress!!! What the hell are you trying to accomplish? Why not just finish neutering the damned thing, ditch the entire EFI setup, toss on a carburetor and get some immigrant children to sit under the hood with flints to take care of the job of those pesky spark plugs?

[boosted to 26psi]

Originally Posted by cre

Oh for the love of all that is considered progress!!! What the hell are you trying to accomplish? Why not just finish neutering the damned thing, ditch the entire EFI setup, toss on a carburetor and get some immigrant children to sit under the hood with flints to take care of the job of those pesky spark plugs?

If I could get away with that I would try it....lol. basically im finishin what someone else started. But I'm juat goin to get the coils an do it right. So now I need to find one