Ac isn’t cold at idle

[L31MaxExpress]

Got a link to said radiator? Efan is better at an idle, engine driven is better when you're moving. One isn't better than the other at everything. Late Crown Vics came with both stock: an efan puller in front of the engine driven fan.

Duramax fan blade moves more air than the 34" Tahoe electrics even at idle. Mechanical fan was better at moving air everywhere than the twin electrics.

 

[Supercharged111]

Duramax fan blade moves more air than the 34" Tahoe electrics even at idle. Mechanical fan was better at moving air everywhere than the twin electrics.

You're the one with the secret sauce on this. What was the setup for the big block again? It was the Dmax blade but I forget which fan clutch? Is it any quieter than the airplane prop supplied by GM? This is what I want for my dually.

 

[L31MaxExpress]

You're the one with the secret sauce on this. What was the setup for the big block again? It was the Dmax blade but I forget which fan clutch? Is it any quieter than the airplane prop supplied by GM? This is what I want for my dually.

If the 454 has the same size fan clutch hub on the water pump as a Vortec 350, 8.1 or LS you can use a clutch for an 07 Trailblazer SS. I used a Napa severe duty on mine. It is quieter 99% of the time than the stock GM fan because the clutch rarely couples. That being said when it does couple it will sound like a medium duty truck for about 20 seconds or so as the temperature gauge plummets. At idle that fan will suck a piece of paper a foot or so away toward the grille.

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[alpinecrick]

Underdrive pulleys can make the issue of poor stoplight A/C performance worse than OEM.

The OEM GMT-400'like trucks in addition to the mechanical fan also come equipped for an "Aux. electric fan as well. Control for the AUX. fan is in the L29 calibration.

Even bumping the idle rpm a hundred or 2 rpm will help, but only really acceptable with non-stock(ie higher stall=looser) torque converters or manual trans trucks.

Here's the OEM GM Aux. electric fans. (notice how teh description staes that for the 5.0/5.7 engines its called an Aux fan, for the L29 its called a "A/C condenser fan)

Description:
"5.0 & 5.7L. Auxiliary. Incl.Fan Blade & Motor./7.4L, ac condenser fan"
https://www.gmpartsdirect.com/oem-parts/gm-engine-cooling-fan-assembly-15717423/?c=bT0x

peace
Hog

That fan goes in the space usually occupied by the external trans cooler. Pinger over in Britain has that on his 2wd Suburban. Doing a little research and talking to others it appears it's an either/or proposition--both the fan and the cooler won't fit in that spot at the same time.

 

[L31MaxExpress]

That fan goes in the space usually occupied by the external trans cooler. Pinger over in Britain has that on his 2wd Suburban. Doing a little research and talking to others it appears it's an either/or proposition--both the fan and the cooler won't fit in that spot at the same time.

Its been a while since I have looked at them but I am fairly certain the core supports have two sets of holes. The pusher fan mounts on the driverside if the truck has a factory trans cooler. Atleast in my 99 Tahoe it came that way. Trans cooler on the passenger side and fan on the driverside.

 

[alpinecrick]

Spectra makes radiators for Napa and Advance. I got a Spectra off of Amazon for half of what Napa wanted and then, when I rammed a drill bit through that, got a replacement from Advance at 20% off online. How thick is your current radiator?

Its been a while since I have looked at them but I am fairly certain the core supports have two sets of holes. The pusher fan mounts on the driverside if the truck has a factory trans cooler. Atleast in my 99 Tahoe it came that way. Trans cooler on the passenger side and fan on the driverside.

That’s good to know. All the photos and diagrams I’ve seen put the fan in the trans cooler location. I can’t recall ever seeing one of those fans in person on a GMT400.

 

[TheAutumnWind]

Underdrive pulleys can make the issue of poor stoplight A/C performance worse than OEM.

The OEM GMT-400'like trucks in addition to the mechanical fan also come equipped for an "Aux. electric fan as well. Control for the AUX. fan is in the L29 calibration.

Even bumping the idle rpm a hundred or 2 rpm will help, but only really acceptable with non-stock(ie higher stall=looser) torque converters or manual trans trucks.

Here's the OEM GM Aux. electric fans. (notice how teh description staes that for the 5.0/5.7 engines its called an Aux fan, for the L29 its called a "A/C condenser fan)

Description:
"5.0 & 5.7L. Auxiliary. Incl.Fan Blade & Motor./7.4L, ac condenser fan"
https://www.gmpartsdirect.com/oem-parts/gm-engine-cooling-fan-assembly-15717423/?c=bT0x

peace
Hog

Installing one of those seems like a great way to keep the mech fan and improve a/c performance @ idle.