1978 Chevy K20 longbed with nearly 500,000 miles! LS Swap begins!

[Nick_R_23]

Thanks! It’s been a real busy summer, and finally found some time to get back to it!

Finished up the last bit of wiring and cable routing, securing the O2 sensor lead, clutch bleed line, and speedo cable.



Sourced a cleaner and straighter bumper for the rear!



Drivelines are being brought into town for either a rebuild or replacement.



The biggest part, updated the tune to include PWM fan control logic! Anyone care to critique my setup? I watched projectgatago’s video, and set it up the best way I could think, seeing as I don’t have a speed sensor on this truck. My thought process is that the fan should be off at 195F (thermostat temp) and running progressively faster at speeds above 200F, and ramping up significantly above 220F. I did RPM based instead of speed, one, because I don’t have a speed sensor, two, because the fan should remain off while moving anyway due to airflow over the radiator, and three, it acts as a safeguard to kick the fan on regardless of speed or engine running if the temp is that excessive. I haven’t tested this out with the engine running yet, as I wanted some feedback in case I screwed up.



I used Holley’s default Electric Fan #1 pin but repurposed it to PWM-



This box pops up when I click ‘Where Used’. Does the port have to be actively functioning (fan on), or did I screw up?



I set this to 190F just to ensure no need for the fan below that temp.

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