ECM & cooling
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Teching In
Joined: Nov 2014
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From: Callahan, Fl
ECM & cooling Not sure if this is the proper place but....Transplanted a crate LS3 into a 67 chevelle. The ECM has a wire labled "FAN", do I still need a pair of relays for the Spal dual fans? Will both fans run when ECM trigers them? How about the A/C switch for the fans? Am I making a mountain out of a mole hill? Appreciate any guidance 
Thread Starter
Teching In
Joined: Nov 2014
Posts: 48
Likes: 0
From: Callahan, Fl
it's a GMPP crate system from Pace. Destructions state to wire fan directly to the blue wire labeled fan. Don't know if both fans run at a constant speed or is there a hi/lo function? Still have no clue what cycles a/c compressor. This is a ground-up resto-mod that's nearing completion...I think
Teching In
Joined: Nov 2014
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From: Sunnyvale California
I have a GMPP LS3 crate also, wired blue wire directly to fan, relay is built into Fuse/Relay center.
I don't see why it wouldn't power both fans. It is set to turn fans on at 207* F.
Not sure on Hi/Low.
It is a 12 volt signal
I don't see why it wouldn't power both fans. It is set to turn fans on at 207* F.
Not sure on Hi/Low.
It is a 12 volt signal
My opinion is that fans are better off run thermostatically
based on radiator outlet temperature, than letting the
PCM guess and meddle. Better to have the radiator
water 20 degrees below block, to have some "surge
cooling capacity", than make thermostat sit there full
open waiting for fans to decide to play catch-up.
Unless your primary goal is to shed load for CAFE
compliance. Which is nobody's other than the OEM.
based on radiator outlet temperature, than letting the
PCM guess and meddle. Better to have the radiator
water 20 degrees below block, to have some "surge
cooling capacity", than make thermostat sit there full
open waiting for fans to decide to play catch-up.
Unless your primary goal is to shed load for CAFE
compliance. Which is nobody's other than the OEM.
