[Robby D]

Hello xperts,

My freshly rebuilt 400 WZ (4bbl MT) is running at about 230 degrees. Is this normal? Is the fact that it is freshly rebuilt a factor?

The engine is .030 over (406 CI), has a Comp CCA 51-223-4 cam (.268 I / .280 E duration @.050, .477 / .480 lift ), matching Comp springs retainers and locks. Using Polylocks and the stock Q-jet (rebuilt). I have a 180 thermostat and the radiator has been reconditioned. The water pump is a cast iron vaned unit. I am trying to determine if 230 degrees is appropriate or do I need to get an oil cooler or aux electric fan.

Any help is appreciated in advance.

Robby D

[Robby D]

Hello xperts,

My freshly rebuilt 400 WZ (4bbl MT) is running at about 230 degrees. Is this normal? Is the fact that it is freshly rebuilt a factor?

The engine is .030 over (406 CI), has a Comp CCA 51-223-4 cam (.268 I / .280 E duration @.050, .477 / .480 lift ), matching Comp springs retainers and locks. Using Polylocks and the stock Q-jet (rebuilt). I have a 180 thermostat and the radiator has been reconditioned. The water pump is a cast iron vaned unit. I am trying to determine if 230 degrees is appropriate or do I need to get an oil cooler or aux electric fan.

Any help is appreciated in advance.

Robby D

[goathead68]

Robby,

230 degrees is a little warm. With a 180 degree thermostat you should be running 195 or so at highway speeds.

Check your timing. Try setting it at 12 degrees BTDC initially. If you have access to an advance timing light, see how soon your advance comes in and what the total advance is. You should try to have all the advance in by 3000 rpm or so and have a total advance of 34-36 degrees. This is a good safe advance range.

Check your vacuum advance unit, too. Make sure that it is functioning properly.

Are you using a fan clutch? If not, it would help to have one of these installed, too, especially in stop and go driving. The fan will be engaged at slower speeds, which will help pull more air through the radiator. It would be a good idea to make sure that all your fan shrouds are installed and in good shape.

Last but not least, make sure that your fuel mixture isn't set too lean. This is not the idle mixture, but the rods and jets that you have on the primary side of the carb. A lean mixture will cause the car to run warm. You'll have to open up the carb and get the numbers off the jets and rods to see what you have here. Another good way to check this out is to check the color of the plugs. They should be light gray in color, not white, which would indicate a lean condition.

I had a similar problem to yours, especially at highway speeds. It turned out that I wasn't getting full advance mechanically. The weight base was binding on the shaft, getting me only 10 degrees or so of advance. Instead of 34 degrees, I was only getting 24. Cars run warm when the timing is retarded. The car would run 225-230 on the highway. I had to disassemble the distributor, clean things up, and reassemble it. The car now runs 195 on the hottest days. It was as simple as that, but it took me forever to find that out. The main indicator for me was the fact that the timing would change everytime I checked it, sometimes by as much as 5 degrees.

These are a few things to look at in order for you to get the problem solved.

Good luck and let us know what you find.

[Robby D]

Goathead,

Thanks VM for taking the time to answer my post. I reposted on "Heating and Cooling" and got some feedback there as well. I went to a 20/80 mixture of coolant and added a gallon of "Cools like Ice Water" from Advance Auto. It helped by about 15 degrees at highway speeds and makes for a slower increase rate up to 230 at low speeds/idle, but still I eventually make it up to 230 every time. I am going to try an oil cooler next, it's cheaper than a Rodney Red or Be Cool radiator.

Robby D