Help with toyota 4agze CAS

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mhiscott
Helpful MS/Extra'er
Posts: 39
Joined: Mon Mar 27, 2006 11:04 am

Help with toyota 4agze CAS

Post by mhiscott »

I've decided to try to use my stock CAS, and was able to scope the outputs of both wheels through my friends scope. We built the circuit to condition the two VR signals G1 and G2 into one input for the MS, but the output doesn't seem useable. Wether there is something messed up wiring wise, or if it's just a megatune config problem I'm not sure. So far we've got the MS with v2.2 board hooked using the relay board, the newest firmware with MSnS-E code has been loaded, and everything is working aside from spark.
The engine is an ae101 4agze with DIS ignition. I've got MSD coilpacks hooked up properly driven by the vb921 coil driver chips (2). The coil trigger wires will connect directly to the vb921s. Another option I guess would be to grind another tooth off the CAS 24 tooth wheel and go about it that way. If that turns out to be the only way of going about this, how would I go about configuring this? Apperently the 24 tooth wheel spins at half crankshaft speed, so to the MS it looks like a 12 tooth wheel.
Infinite thanks to anyone who can walk me through this, the engine is ready to start aside from this last issue!
Thanks,
Mike
thechuckster
Experienced MS/Extra'er
Posts: 294
Joined: Fri May 07, 2004 5:38 am

Post by thechuckster »

there's a few folks using the toyota sensors inside the dizzi:
<http://www.msefi.com/viewtopic.php?t=19002>
<http://www.msefi.com/viewtopic.php?t=12830>
<http://www.msefi.com/viewforum.php?f=57>

fwiw: i've used the VR sensor from an old 22RE dizzi for my setup - i've used the LM1815 chip instead of the analog zero-crossing circuit to handle the input. So far (i can slow-fast idle but that's about all) it provides a good signal from cranking and higher speeds.

given that you're running waste-spark (2 coil drivers), it would be simpler to just run the 12-1 wheel option (punch off 2 teeth) and ignore the single-tooth triggers.
RA40 + 18R + Turbo
MZ10 + 7MGE = track barge!
lmr052
Experienced MS/Extra'er
Posts: 364
Joined: Sat Dec 11, 2004 10:27 pm
Location: NW Sydney, Australia

Post by lmr052 »

To use the CAS unmodified, you will need 2 VR conditioners, 1 for the NE which goes into the normal tach input, the second for a combined G1 and G2 wired up for a second input.

Regards, Richard
Successful MS Replacement for OEM Toyota ECU - all stock sensors and 2nd Ignition Input.
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