Rear mounted radiators- lets talk about it.

[rustywrench]

i'm putting the rad in the rear of my 37 packard. i'm hoping to actually make the mounts and put it in tomorrow, i'll get pics, pete.

 

[shizzy]

I think just putting a piece 4" or so below the bottem of radiator will push plenty of up into it. I am using a puller fan out to the rear.
If the air at hwy speeds push in a certain direction in you application, you would want to mount your fan to push or pull in the direction of natural air flow.
Sometimes you want to duct the exhaust side so the hot air doesnt just roll around to the intake side of the radiator.

Interesting point. Im wanting to put the radiatior in the back of the truck Im planning. is it better to put it in the front portion of the box or the rear due to air flow over the cab? I dont want to put it in an area where the air just blows back around. Im just thinking of every truck I have owned and watching the leaves pin circles behind the cab at free way speeds. I did plan on ducting air from underneath the bed, so is that going to pull enough so it wont matter? I have already figured Im loosing half of the bed area for the gas tank and radiator.

 

[racer93]

keep it cool

Mounting the radiator in the rear works fine, several have hit the key to keeping it cool, electric fan(s) being able to vent the exhuast side out and The biggest thing I did to a racecar with a rear mounted radiator was get to purchase some additive that is made to drop the temps. I used some stuff called "wetter better" that dropped temps 15 degrees while racing. There's other brands Royal Purple has one that drops temps more. The only time I would see an issue with a rear mounted radiator would be in heavy traffic with no air flow, but hell you would have that problem if it was mounted anywhere.
You can cool your engine also by running your oil thru an oil cooler, there's plently of old motocycle radiators that work great as oil coolers. Cooling the oil helps keep the engine running cooler and it's cheap horsepower, not alot of horsepower but it's cheap horsepower.

 

[maddog]

Thanks everyone, some real good info here.

Racer93, what is the optimum temp for making more horsepower? I'm not planning any circle track events with my Fiat, just curious.