Please check my logic on a cooling issue.

[pilotblake]

Ok I am running a small block chevy with a custom built aluminum radiator that is roughly the same size as the stock 4.0 radiator, with 2 electric fans that run full time no mechanical fan. Anyway I have a 160 thermostat in right now and in 60-70 degree weather will overheat after 30 min of crawling around (240ish). Anyway my first thought was to slow down the flow through the radiator with a restrictor to maybe get more contact time in the radiator. This is the link that I followed. http://gojeep.willyshotrod.com/HowtoRadiatorRestrictor.htm. I started with the 1/2 and it is still overheating, but this seemed to slow the process slightly. Here is my other thought. Even with the engine temps up to 200 (before and after the restrictor)I can put my hand firmly against the radiator(in front of the fans) when it is idling and it is barely warm. With my hand on the radiator I run the throttle up and in a sec or two I can't keep my hand on the radiator. SO with that being said should I be trying to speed the flow up through the radiator? I have tried no thermostat at all and it still eventually overheats just at a slower pace. I want to try everything I can with my current radiator setup before I replace it, so I am open to any ideas.

[mkbruin]

bad water pump, or air in the system?

[pilotblake]

Water pump seems to be working properly and the system is free of air. My question is since the radiator is cooler to the touch when idiling as opposed to reved up, does tht mean I am not getting enough coolant flow? My original thought was to slow down the flow, but maybe I should speed it up. :wall:

[aemsee]

sounds like there is not enough flow at low speeds. Maybe just a pully size change, or a high volume pump. How many rows is the radiator?

[dakal]

x2

[89comanchesleeper]

how close are the fans to your rad? if there to close the fans won't have much bite/pinch to pull the air through the rad. you might want to try to put a 1/8 in space between the two.also the best rad ive seen for tight fits like s10 v8 swaps is a corvette one core rad. and if water moves to fast through it there won't be much time for the water to cool. i can't recall the name of it but theres a additive you can add to the coolent to drop the boilin point and lower temps. are you runnin a hearter core. they help out to. oil cooler would add a little help also. is the truck a dd also? you could always put the rad in the bed. it would give planty of time to cool and would add with not bein under the hood with engin temps. hope this helps you any :cheers:

[pilotblake]

I am down to a remote oil cooler, and remote radiator unless I can come up with something else. It is far from a DD just something to keep me out of trouble. My issue with the bed mount radiator is that it will cook everything in the bed. I haven't looked into the dimensions of a corvette rad, but I am running out of ideas. This is my last ditch effort to start cheap and move up to get this thing to the point I can take it out and run it.

[Pete M]

get yourself an inferred thermometer and check what the temps actually are. :thumbsup:

 

Is the hose exiting the radiator hot?

[Gilbertond]

I once installed a 350 chevy in a toyota landcrusier, with the original radiator. Had all kind of temp problems. The final solution was when I got the pulleys from a car with factory AC, the engine pulley was bigger and the pump one was smaller, then I installed a tstat, climbing mountains in low gear for half hour would not move the needle up or down when I was downhill