Head temperature

j_macy

Member
I know that one head will always run hotter than the other
Can anyone clarify what an acceptable difference might be?
 
I just measured mine and the right head was 20 degrees hotter than the left head both with the heater on or off. Engine is newly rebuilt so don't think this is a sign of any problem at least not one that I'm going to worry about.
 
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My FR flattie runs about 10 degrees hotter on the passenger side. Don't know why but seems to be a common condition among others I have talked to.
 
I have two AV8's and both have one head that runs hotter the other side, switched gauges and no change. Happy with them...
Vergil
 
All my old Fords with Skips pumps read within 3 or 4 degrees of each other. If useing a laser gun if you don't hold it the same distance away at the same angle and hit the same spot the temperatuures can vary. G.M.
 
wasn't the hotter head the passenger side??...because of the exhaust pipe crossover??....lots more exhaust passing by that side??...Mike
 
Using Skips pumps on one 8ba and Speedway pumps on the other, each head has its own gauge, both engines have new radiators and both read one head higher temp than the other, maybe 10º-15º.

Vergil
 
With fairly substantial differences between the two sides of the engine being quite typical (measured my neighbors 59A-B this morning, 20-30 deg diff) it doesn't look like anything to worry about.
 
If you are reading the temperatures right and it is that much differenceI would look into where the problem is. I have never seen an engine with much over 4 or 5 degrees difference on both heads. You can get variations if you don't hold the gun the same angle, the same distance and vary in the spot where the temperature is taken. The only time I saw a big difference was years ago when I modified the the first impeller on the 33 of mine that was over heating. I put the one modified pump on the right side and it cooled the right side by about 30 degrees cooler than the left side. I swopped sides with pumps which you can do on 32 to 36 engines and the left side was now 30 degrees cooler than the right. The old original pump was pumping 55 gallons in 5 minutes and the one with the modified impeller was moving 92 gallons in 5 minutes. I made another modified impeller for the other pump and both sides were within a few degrees of each other. Skip has modified a large quanity of pumps and reports from most people was at least a 20 degree improvement. G.M.
 
I have previously explained the technical reasons for the passenger side of the engine block to have more heat to contend with. It is completely normal for head temperature to be several degrees warmer there if both banks of the engine have similar coolant system capacity.

The exhaust port length, extending through the block casting, is longer on the passenger side of the engine allowing more exhaust heat to be passed into the coolant. At the same time, the intake port casting length, which has a cooling affect, extends further into the block on the driver's side.
 
My head temperatures are actual reading and never vary very much on either side. I would describe this as several degrees. You mention several degrees, what would you describe as several at 180? One poster mentioned 30 degrees difference, I don't consider this normal. With Skips pumps delivering almost twice the flow as stock pumps, 110 gallons in 5 minutes verses 65 for the stock pumps on the 37 to 53 type pumps the additional water flow MAY take the extra heat away faster on the passenger side so that it has no effect? G.M.
 
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