CobraLS

Swapped a 5.3 LS into a 350 hole last year, with Fitech EFI and the 6014 MSD ignition. Starts and runs great, ran it all season last year, but continues to come up with a cam sensor fault. This is a rear cam sensor, so if I have done my homework, the pin swap on the harness does not apply, correct? The harness plugs are to the correct banks, and I have worked, added, and reworked grounds. I know this topic has been beat to death, but any additional input would be helpful.

Most importantly, I would like to find a way to re-establish momentary ignition interruption for shifting. I think that by applying 12V to the blue wire of the 6014 would work if MSD would rework my box to drop the minimum rpm below the standard 2000, but they don't want to do that. I have tried different approaches, but the momentary function is difficult to accomplish. Everything I have tried stalls the engine, because I cant re-establish spark quickly enough, and the engine stalls. Hard to carefully maneuver a boat at the dock....

Doug G

So it won't idle under 2000 ?.... IF I'm reading right.

Shifting forward to reverse ? or does this boat use some sort of gearing ? (not a boat guy)

Sacrilege

iTrader: (1)

Don’t drop spark, drop fuel. Put a kill switch on the injectors. A possible lean condition doing it this way isn’t going to mean a thing under no load at low RPM.

Doug G

OR, maybe one of these guys can help ?

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CobraLS

Thanks for your input guys. If you were trying to park a car with a manual transmission, you would need the clutch to unload the powertrain to shift from forward to reverse. This shift system uses a dog clutch that has tapered sliding gears. Going into gear uses the taper of the tooth, and once engaged, uses the straight side of the tooth for drive. Even at an idle, the prop is still turning, and the load remains on the driveline. The momentary ignition interruption unloads the straight drive side of the tooth, to allow coming out of gear. It is the momentary stumble that I need to create, coming out of gear. For many years, boat manufacturers have used an ignition interruption system to accomplish this "coming out of gear relax of the load on the drive". I have attempted different methods with my FITECH efi, and the MSD box, and basically the "momentary" is what is difficult with both systems. Taking power from the injection does not work because it needs to go through its start up sequence again, and the MSD is the same in that regard. I am wondering out loud now if there might be a way to turn off the injectors as opposed to powering down the entire ecu, and potential side effects of that. What would you think of switching the ground to the coil packs, ie a momentary loss of ground, which would be easy to accomplish? any potential negative side effects to that? Thanks again all, any input is appreciated.

Sacrilege

iTrader: (1)

I don’t mean tell your ECU to cut fuel, I mean literally cut power from your fuel injectors. They should all be on one fused circuit. Put a relay in there with a momentary “normally closed” (NC) switch. The relay will be on whenever the ignition is on, but as soon as you hit that button, it will cut power to the relay and kill the fuel injectors. It is a very simple solution to a very simple problem, you are way over-thinking this.

CobraLS

The blue wire on the MSD 6014 is intended for launch rev limiter, so if I apply 12 volts, the desired launch rpm is programable from 2000- 10000 rpm. My thought was to use this circuit if I could drop that 2000 rpm factory MSD preset to less than that, and I could play with that preset until I have enough loss of power for the gears to disengage, which might be the momentary 0 rpm. It is laptop programmable, but not outside the 2000- 10000 rpm.

CobraLS

I see your direction Sacrilege, but the fitech system houses the injectors and the ecu in a throttle body configuration. I am not sure that I could access that (those) circuits independently, but will have a look.

Doug G

Doesn't that box have a 2-step function where you can set the RPM to what you want and have a button on the shifter to activate it ?

Could that do it ?

CobraLS

Yes Doug it does, but the range preset does not work in my application, and MSD will not modify it for me.

LLLosingit

iTrader: (4)

I looked at the wiring diagram for the 6014, It has individual wires for each coil. Here is my thought.... 4 relays wired to control 4 coils that are activated by momentary switch. When activated it would drop power to only 4 cylinders instead of all of them, This would decrease rpm and power considerably.

Mark Anderson

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