: Cooling requirements

03-09-2007, 06:11 AM
I got a Volvo intercooler and looks like the distance from the inlet to the outlet is going to restrict my radiator width quite significantly, to about 22.5". If that radiator is 20" in height, that makes for about 450 sq. inches of core surface. The rule of thumb for gasoline engines is that you wanted 1 sq. inch per cubic inch of engine displacement. I suppose this varies for diesel engines, specially for turbocharged engines.

I plan on using an HY35 turbo, the Volvo intercooler and to tweak the pump to about 180HP. The truck will be occasionally used to tow a 4400 lb car. Will 450 sq. inches of radiator be enough?

03-09-2007, 06:19 AM
I use a pretty small aluminum radiator (24x18x3) it does the job fine. Diesels stay cool easier than gassers.

03-09-2007, 11:51 AM
Yep, what mooktank said!

I just installed a winter front [a piece of plywood] in front of my radiator so the engine would warm up above 160*. It covers 2/3 of the radiator and now engine runs at about 180* and I actually have a working heater again! I've never had to use the electric fan yet. The previous engine, a Dodge 360, would quikly get up to thermostat heat of 190* without winter front using same radiator.

03-09-2007, 12:49 PM
I definitely recommend an electric fan so you're not wasting all that hp all the time turning a fan. Mine seems to be perfect it will run all day in the cold at 195 and I have nice heat.

03-09-2007, 01:07 PM
I put in my response over on this other thread... Hope it helps...

03-09-2007, 01:48 PM
At this point I'm thinking of going to a junkyard and getting the largest radiator/electric fan combo I can find that will fit with the Volvo radiator. Thanks.

03-09-2007, 02:51 PM
Considering the size of the electric fan that is on the P30 chassis, it does have a very large radiator, that trying to keep the 4BT cool isn't a very big problem. IMO the best junk yard fan to look for is one from a Ford Taurus (http://cgi.ebay.com/ebaymotors/90-91-95-Taurus-Continetal-Sable-Radiator-Fan-3-8L-Assy_W0QQcmdZViewItemQQcategoryZ33600QQitemZ160090 462658QQrdZ1QQsspagenameZWDVW), by far the most air flow of junk yard fans. It is a two speed fan so here are some wiring suggestions (http://www.tacomaterritory.com/~dickfoster/Pics/Taurus%20Fan%20Wiring.pdf).

03-09-2007, 03:51 PM
it would be pretty easy to add but I used illuminated switches, one for fan off to warn me I had turned it off if I was doing lots of water crossings & such, and another for a high/low. But honestly not sure I needed the high low.. I used the cheapo autozone hayden switch, which I would not use again, I'd use a screw in fan switch from summit racing or something like that, about the same price, more reliable...

Also a note, go to carquest and use 40 amp inline fuses.. they sell them, they are rare though, versus 30 amp. once in a while a Taurus fan will blow a 30 amp fuse...

03-09-2007, 04:36 PM
The radiator I mentioned above is about 26" X 20", 3 core. Electric fan is maybe 13"-14", sits back from core at least 4" and uses no shroud of any kind. Coolant temperature sensor actuated, with manual override.