I'm using a 1936 Farmall H tractor radiator in my T coupe in front of a Buick 401. I haven't had a chance to take it out yet, but am wondering if anyone knows how to calculate whether or not a certain size radiator will cool a certain displacement engine? I realize there are TONS of factors, such as vehicle weight, engine hp, etc. but is there a "rule of thumb" way to figure out if you can expect a given radiator to cool a given car?
The only one I've come across was in a book on air conditioning by the proprietor of one of the street rod air-conditioning companies. I can't remember what got me to reading it because I've never had any aspiration towards an air-conditioned car. I ended up copying that page, as it was the only one that was of any use to me. Unfortunately I don't have the copy with me, but if I remember correctly it starts with a base figure of double the engine capacity for the core volume (w x h x t). That sort of gives you an indication of roughly the size of core to think about. The base factor (i.e. 2) is then modified by a lot of things. There's a sort of checklist that you go through adding .1 for this and subtracting .2 for that, to bring you to a final factor, which you multiply by the engine capacity. Does anyone have a better formula? By the way, can anyone tell me how much practical width there is inside a Deuce shell?
Found it: I was looking for it myself, because I found a very leaky BMW 728 radiator that I'd forgotten I had. Radically narrowed with a new core it'll just work in the '31.
Equations are great but here's the real situation for that T Your radiator height/width is determined by what looks right on that tiny car, and it's not a huge radiator. OK, the solution must be a thicker radiator. Except there's diminishing benefit for each "row" because previous rows heat the air. Thus you don't really see 5 and 6 row radiators. So really the question is how undersized is the radiator? It's a problem faced by every high horsepower T in existence. Do your research on water pump pulley drive ratios, be sure the fan is moving a ton of air, use vacuum advance, and you'll probably be fine. Neat chart posted by Ned. Lotta variables when ya start thinking about it. Good luck!
Thanks, Ned Ludd, for the great chart. I knew there had to be something out there that could give me a ballpark idea of what radiator size to shoot for. I realize that every vehicle is different and there are always a million variables, but at least this gives me a good base line starting point. I am currently running a Farmall Model H tractor radiator because it fit between my frame rails. The radiator is old and not that great, but I haven't had any cooling problems in the 250 miles so far. I'm testing the car with this old radiator and if it works throughout the summer I'll be ordering a new radiator (same application) to install over the winter. Thanks guys......I love the HAMB!
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