Thread: 331 hemi from a new Yorker what temp is safe

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As far as posting pictures, the easiest way I've found is to link to a photo server like photo bucket.

Here are a couple of more thoughts for what it's worth.

The first thing I'd try would be to replace the restrictor with a thermostat. When I first started driving my 354 I was running a 160 thermostat and it would run well above that temp and get very warm (over 220) on hot days pulling hills with the AC on. I switched to a 190 thermostat, and now it normally runs 190-200, and under load with the AC up 210 (where the fan clutch locks).

If the thermostat doesn't cure it the next area I would look at are the stock pulleys. As I recall, the stock waterpump pulley is huge and actually larger than the crank pulley (basically you are underdriving the waterpump). It may be a case of the pump not being able to move enough coolant at higher RPM.

I also wonder about the possibility of the radiator and fan being in an area that becomes a low pressure area at speed, limiting the amount of air that is available for the fan to actually move.

Jerry you're right about the temp sender location (and I remember the discussion about locations from a while back). Anyway the location choices I had were the back of the intake manifold (on either side) or the crossover. I picked the crossover because I feel that lets me see temperature from both sides of the engine rather than just one.

One of the things I personally found really interesting is using an IR temp gun at various locations on the engine to see the differences in certain areas (one thing that really surprised me was how much the temp drops from the thermostat housing to the radiator inlet).

Mike's right - you had no problems on short runs, running around 190F or less, but on a longer road trip temps went up. That does not fit with an air block, but it does fit with air flow through the radiator being restricted by air over the cab/bed area, or coolant flow problems like the pulley size. I'd check out Mike's suggestions first, and I would definitely try a thermostat.

I thought about maybe standing the rad up in the back and replace the tailgate? What do you think? I am going to put the thermostat back in 190? The helper pump I have is for a race car 1" in and out. And maybe disable original pump or not if the rad works???