Choosing the right condenser for a custom AC sistema.

[bohica2xo]

Nice video Chris.

I have had good luck with the GM 15229250 fan if you have room (20 inches) It can be loud with the clutch locked, but it does move the air.

[Carguychris85]

1580690 is what I am running. I had to trim about 1/2" off the end of the blades. I followed the originol contour and used the first trimmed tip as a templete for the rest. Balance did not seem to be affected and the blades are easy to trim with a sharp pair of scissors.

[bohica2xo]

Yeah you can't trim the 15229250 with the inducer ring, but the fan shroud is not as important either.

Are you running the 15-4958 electric clutch?

[Carguychris85]

I ran the 2007 TBSS thermal clutch for a while. Then I swapped over to the electric clutch. Initially I had a 16" electric puller sandwhiched between the radiator and clutch fan that was on a relay tied to the Fan1 PCM output and the electric clutch was on Fan2 via a simple relay. The clutch fan mostly freewheeled and the electric fan came on with the ac pressure or engine temp. The clutch only fully engaged when the temps climbed or the ac pressure was elevated. I have since implemented the EV clutch logic in the PCM and deleted the electric fan. My 97 van runs on a 2005 P59 PCM using a mix of GM segments from 2 different vehicles. Mexico had the L31 350 alive and kicking in the GMT800s through about 2007 so it was an easy thing to get up and running. The code that ran the clutch is still in the operating system that runs my van, so I added a solid state relay and a few wires gaining me PWM control of the clutch. You almost cannot make the thing run warmer than 200°F.

[bohica2xo]

Nice.

Being able to pull the fan speed up when you need airflow over the condenser regardless of ECT is handy.

[Carguychris85]

Nice.

Being able to pull the fan speed up when you need airflow over the condenser regardless of ECT is handy.

It does more than that. It responds to transmission temperature and at WOT if the engine/trans is under programmable temperature limits, it will soften the clutch for less power loss while you are trying to get up and go. At WOT it will release the clutch allowing the fan to freewheel.

[bohica2xo]

Yeah I don't have that kind of flexibility on an A9L ECM. Nice that you can do all of that

[andrew vanis]

Nice.

Being able to pull the fan speed up when you need airflow over the condenser regardless of ECT is handy.

It does more than that. It responds to transmission temperature and at WOT if the engine/trans is under programmable temperature limits, it will soften the clutch for less power loss while you are trying to get up and go. At WOT it will release the clutch allowing the fan to freewheel.

That is very cool. Nice how you were able to custom the car computer to make all that happen.