MSefi.com read only forum (Jan.15,2018)

Hello from Down Under to all. I hope someone can help me. I have a MS 2 which worked fine with the stim. The idea was to run 16 LPG injectors on a 351 Cleveland. [2 banks of 8]. When we tried to run the engine the D37 plug fried where the driver wires go through it. There are no shorts anywhere and every thing is wired correctly [been checked more than once]. The wires are not burnt just the plug and the end of the board. The injectors are 1.5 ohm resistance. I have ordered a new MS 2 as the damage looks too great to fix and I do not want a repeat happening. The reason for LPG injection is I am chasing a LPG Land Speed Record on a salt lake in Australia.

What did you have PWM current limiting set to? If the current limiting is off, you'd be trying to feed ~160 amps of current through four pins rated at 5 amps each. To hold these to a 1 amp hold current (per injector) would need a 10% PWM current limiting amount, which would put you within safe limits. These may need an external peak and hold board, like the JBPerf one.

Thanks for the reply Matt. Yes the current limit was set to on. The guy who built the MS 2 for me thinks that it would be a good idea to build a driver board with only two injectors per transistor. He's the computer geek, I build engines, does this sound like a good option. He is able to do this he says. I think I have come up with a way to duel stage the injectors using the output from a shift light to operate a relay and power up the second set of eight. So start on two banks of 4 and at 3500RPM switch to
two banks of eight [Two per cylinder]. Thanks Alan TPVM.

MS seems happy with 4 low impedance injectors per driver - after all it comes from the land of the V8. ;-)