Coolant Fan speed seem low

[billygraves]

I have a 1999 Pontiac Grand Prix. 3800 Nat Asp 4T65-E. I recalibrated the fans to turn on earlier with my 180 stat and with lower A/C pressures. I have the single speed motors and not the larger PWM Motors. I have a fan connector with 12 gu wire, disconnected each fan and installed my connector, connected it to Bat + and Neg. The fan runs at the same speed.

The fans do run and cool the system ok even with the A/C on. I find the fans are quite and other GM Fans, like a 1993 Sunbird 3.1L fan moves twice the air BUT make more noise.

 

My question is this. Has anyone tried to replace a fan motor with one that has a higher RPM in a 3800 Nat Asp cooling package to gain faster cool downs? I am trying to gain more air flow by trying to find a fan motor that runs faster to pull more air. Noise is not a concern.

 

Thanks for your time. I do not have a service manual for the fan system. It does not seem to have a low spd. SEEM is the key word here.

[George]

I made a shallow shroud for my 1986 Buick Grand National so I could put (2) 14in slimline fans in place of the factory single fan for a total airflow of 3075 CFM. Very nice. You could do something similar, of course the fans they have now flow more air and draw less amps. Seems be cool has some that look like the old aluminum flex fans that flow 3000 CFM each for a 12in fan. That would make for a very quick cool down.

[Galaxie500XL]

Generally, in my experience, when they get slow, they're about to die, and a new motor is usually much faster, so there's probably no need to mod, just replace the motor with the original type.

 

I've replaced far more slow fans on my cars that were beginning to overheat, than completely failed ones.

[RobertISaar]

if you need them, i can pull the fan diagrams. i'm sure you're aware of the 3-relay setup used to operate them as a serial circuit for low speed and parallel for high speed?