Installing VEMS V3.3 in a Suzuki Swift GTI 1,3 16v mk1 used fore rallycross.

I have made a adaptor from the original harness to the VEMS box + a new wire to the ignition-coil (disconnected the original) because it originally is mechanical-ignition.

The box was mounted in one evening and all was working but the trigger turned out to have problems af hi rpm..

Here is the trigger-signal: (1:10 probe used and scope don't correct fore it)


When running pin 5 on LM1815 to +V the trigger-signal starts dropping out when reaching 5-6000rpm..

When running pin 5 on LM1815 open it gets triggered by spikes/noice at hi rpm.

In both cases it gets worth with longer (you mean shorter?) dwell time.. when runnig 1.5ms dwell the problem is almost gone, but it looks like the dwell-time originally is rather long! (1:10 probe)


Other ways to improve the trigger-signal