Frankenstein 454 swap. Overheating at idle.

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Bextreme04

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Nice! Glad to see it work out. I'll be putting my big block radiator and fans in soon as well.
 

83Burban

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@Bextreme04

When fans kick on, I lose between 150 and 200rpm at idol. Drops down to about 600ish. Is this pretty normal? All seems to be functioning properly otherwise. Maybe set idle a little higher than recomended 800rpm?

One time while crusing around today it stumbled a bit at take off....almost killed it. Think fans kicked on just as I started to give it throttle.

Everything else was flawless.
 

Bextreme04

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The fans are a big power draw... but you have dual batteries and a decent sized alternator, right? It shouldn't be drawing more than 30-40amps total as they run. The GMT400 serpentine alternator I have for my 454 is a 110amp, the stock 80's one is like 40amp or something silly. How do you have the second battery connected?

Is it on an ignition activated relay with a large 4-8ga wire? How are you feeding power to the fans?

There is a solenoid that mounted on the front of quadrajets to kick up the idle when the AC was activated, that might be an option.
 

Matt69olds

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The fans might draw 60-70 amps at startup, then settle down to a much lower draw. Mount the relays as close to the battery as possible, go overkill on the wiring.
 

83Burban

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Hmm...never got alerts for last two posts? My bad guys.

I'll post pics of my "Painless" fan relay wiring set up. Its not actually been "mounted". The previous owner installed it directly between the fan shroud and the motor. Had been spliced SO MANY times and with the toaster oven conditions in the engine compartment it was cooking off the relays. One of the longer wires was made with 3 colors of wire...all different guages.

Lol ive got it mostly sorted now....its just not been "installed".

If weather holds up today....ill make a video detailing the lay out and see what you all think.
 

83Burban

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The painless wiring harness has three (3) 40a relays and a 70a fusible link. Forgive the mess. I'm still sorting it out. It will all be put in a propper wire loom once I know whats what.

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Rusty Nail

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Looking at your picture again, the serpentine belt drive is not factory. Homemade, not working with that water pump. Also does not have a very good rap around the power steering pump pulley either.

I believe you need to address the belt drive system.

X2
There us an ASSLOAD of deflection in that belt scheme.
 

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