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Injector resistors for MS II 3.57

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Hey guys, I have a 1976 280z with a turbo swap, and I'm installing megasquirt 2 3.57. I got new injector pigtails and decided to build the injector harness from scratch. I wired cyl 1,3,5 and 2,4,6 togryher , because I know these engines run batch fired and figured that wouldn't hurt. I want to run resistors for these injectors, and I failed to think of that before assembling the harness. Does anyone have input on what resistor configuration to use to run this? Do I need to rip it apart? Thanks in advance.

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This is how I did it.




3 x 10W 6 ohm resistors in parallel for each bank.  I forget which online electronics parts store I bought them from, but they're cheap.  The conductors are solid so not forgiving of flexing over time.  So mount them solidly and tie the wires down and you'll be fine.  These have been in for 8 years now.

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There's no need for injector resistors.

I'll agree for a street driven car.  However, using PWM on the track did not work for me.  I was at a very warm track day and the car would intermittently lose power for a few seconds towards the end of the session in the afternoon.  The logs showed going full lean.  After eliminating spark as a possible culprit, I hypothesized that the injector drivers were overheating.  Of course, there was no practical or safe way to recreate this away from the track, so I added the resistors and have never had the issue happen again.  It may just be a combination of issues unique to my car and injectors, but using the resistors is simple, cheap and reliable.  And given the cost of a track day, I didn't want to spoil any more sessions.

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