cooling issues

[383hatch]

I am having problems with the car wanting to get hot on the highway, whereas in traffic it runs plenty cool. I have an electric water pump drive, 3 row copper radiator, restrictor plate, stock (newer) water pump, and new hoses. This has been going on since everything was new. It runs good when I stop completely, but once I get moving it wants to heat a little, then once I get to cruising at 2700 rpm, it really gets warm.

Would this mean too big or small of a restrictor plate??

[72Chero]

any number of things can cause overheating.... timing is a big one... if your timing is not set properly and its working harder to run at higher speeds it will overheat especially under a load, do you have a quality water pump, if that motor is built up nicely which it sounds like you may not have a high volumn water pump with has more fins inside to move the water more rapidly... another thing to check is how far the fan is away from the radiator...do you have a four blade or six blade fan... a six blade fan would be better and you should have a shroud to help circulate and keep the radiator cooling. Have you flushed the radiator recently? it may have junk in it and lastly.... what is in front of your radiator...do you have other coolers that may be blocking the cooler air from your radiator...

[383hatch]

any number of things can cause overheating.... timing is a big one... if your timing is not set properly and its working harder to run at higher speeds it will overheat especially under a load, do you have a quality water pump, if that motor is built up nicely which it sounds like you may not have a high volumn water pump with has more fins inside to move the water more rapidly... another thing to check is how far the fan is away from the radiator...do you have a four blade or six blade fan... a six blade fan would be better and you should have a shroud to help circulate and keep the radiator cooling. Have you flushed the radiator recently? it may have junk in it and lastly.... what is in front of your radiator...do you have other coolers that may be blocking the cooler air from your radiator...

I think my timing is the big issue. I only have about 34 degrees total, 31 at idle. Would that be too low for cruising?? I am gonna have to start mixing race gas in with the pump, because my spark plugs are saying too much timing on the ground strap. My pump is stock, but new. I have an electric fan, and dont feel any air around it, only behind it. I dont believe its the radiator, because it has done this since its new, and its the second radiator as the first one leaked busted. Oh, theres nothing in front of the radiator.

Thank you for the input.

[Daffy]

I would go to a larger restrictor and see if that changes the situation...Sounds like the coolant volume is low to me

[7d8ss]

Make sure all factory air dams are in place & functional. Sounds like the air is being restricted or diverted at highway speeds. Just something to consider. Jon

[Letsrace]

I have an electric water pump drive, then once I get to cruising at 2700 rpm, it really gets warm.

I'd be willing to bet that the electric water pump drive is the problem. I've seen it before. The electric pump drive does not move the volume of water/coolant needed at highway speeds. That's why it gets hot at high RPM's.
Electric pump drives are great for drag racing because they allow you to cool the engine after a run without running the engine. But they are not recommended for street use because they only run at a specific RPM, say 2500 RPM, that may be fine at idle or low RPM but when you get on the highway running 3000 RPM then the coolant is not keeping up with the engine and thus not cooling enough. Also, no matter what anyone has told you....use a thermostat!
The things the the other members have mentioned here are all possibilities but I have seen this scenario before, the solution was to get rid of the electric pump drive and use the traditional belt to crank drive. JMO, but I'd bet that is what the problem is!

[383hatch]

Now what if my compression is too much? I am only at 32* total timing, and my ground strap on my plugs are saying too much total timing. Would it be a possibility that the combustion chamber is getting so hot that theres no chance of cooling it down?

[kzo57]

I'm for running a thermostat, they make 160 and up!! I've run a 180 all the time and go back to the stock water pump. And I'm with "Letsrace" the electrics are great for racing. The water has to stay in the radiator a while to cool it, may be flowing too fast to do any cooling. I have a .030 over 11to1, 427, 4 tube vertical flow radiator and use a flex fan and have no problems even in traffic or the Hwy.