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ls1 alternator load

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hey, so Ive been tuning my ls1 swapped landcruiser, I've just put a new cam in it, and I have it idling nicely where I want it, but im trying to figure out how to account for my lightbar and or winch load, cause it pretty much wants to stall out as soon as I use them while idling. I see options to up the airflow for the thermal fans, but dont know what to do when it comes to alternator. and ideas how to get around this would be greatly appreciated. thanks

I assume you have a mechanical throttle?

With some 'tunes' they haven't optimised the idle ignition advance and you can sometimes add a little more below the point you want it to idle. If it's already optimised, you could pull a little from the idle and just above it, adjusting the idle stop to compensate. Both these are so the engine runs more efficiently as the rpm drops, reducing the tendency to stall.

Another, potentially better, option is if you can modify the throttle linkage, somewhere, to incorporate a solinoid, or stepper motor, switched from the light bar, and winch, that physically increases the throttle opening when they're switched on.

Another option is to use some form of hand throttle such as a knob attached to a cable that can be turned to increase the throttle opening - some vehicles use this with PTO's - but while it may be OK for winching, it might be a pain for the light bar.

its out of a vz commodore so its flybywire sadly, ill have a play around with the ign timing and saw a stall protect table under torque management so I might see if it does anything

Actually, drive by wire is the better option. The ecu should be opening the throttle to maintain the idle speed to counter the load.

As the vehicle is still stalling, and I assume it has an idle target speed set already by the ECU, I would start looking elsewhere. My first thoughts are where the winch and light bar are wired into the vehicle, as the voltage drops they introduce may be throwing some sensors off and compromising the ECU's data. Having each independently connected to the battery - both power and earth/ground - may make a significant difference.

However, as it's a 4x4, and both those have a heavy draw, with a good chance of draining the vehicles battery/batteries, I would give some serious though into installing another battery and running them both of that. The advantages being it would isolate the vehicle's electical/electronic side from the drop those would apply, and you'd have greatly reduced concerns about accidentally discharging the battery with extended winching and/or low rpm use of the light bar with night crawling.

If you go that route, I'd be considering the use of dual alternators, or a dual output alternator, rather than using a splitter - but $$$s. Some specialists can offer outputs of 150A, or more, at idle speeds and a lot more as RPM increases - using an LS based engine gives a lot of options as it's a common base engine.

Sorry I can't be of much assistance - anyone else?