makes you wonder why coolhead keeps using them fins on the back side of the chamber. not to mention the jacketing likely has the water volume increased. other than the fact that you can take a blank dome and machine it to nearly infinite chamber shapes and locate the spark plug where ever desired but other wise i see no value in the cool head style of head. other aftermarket heads look to be just copy cats of the coolhead more or less. maybe these aftermarket heads are part of the problem why people have heat issues
There is nothing in these billet heads mentioned above to direct the coolant between the fins on the domes. The fins fill up with steam bubbles and do not escape at the rate they are being formed on the surface of the fins. The steam bubbles keep the coolant from coming in contact with the hot surface of the dome. When this happens this will not cause the engine to have high coolant temperature if the radiator is of adequate size and getting the right amount of air flow through it.
We have design errors like this plaguing the aftermarket performance industry. These guys have the skills and equipment to make just about anything if they are handed a blueprint that is the result of using basic engineering principles and testing. The unfortunate part is they do not understand thermodynamics, fluid mechanics and heat transfer well enough to design parts that do what they are advertised to do.
Moto-cross engines, woods engines, and cross country engines do not usually run at max load for long enough periods of time for the symptoms of ill designed heads and coolant passage ways in the cylinders to ever raise their ugly head. These engines are plagued with bumpers with number plates, bumpers with air stopping grills, bumpers with cow catchers on them, shock reservoirs, designer radiator grills, and ill designed air scoops that keep sufficient air flow from getting through the radiator.
The symptoms of ill designed heads and coolant passage ways in the cylinders of salt flat racers, road racers, enduro type shifter karts and other applications that spend long periods of time at wide open throttle will show up very quickly even though the coolant temps may be below 140 deg. F. Improperly designed coolant passageways will show up as hot spots within the engine and will raise their ugly head when coolant temperatures are low.
If you are experiencing high coolant temps, this is not a symptom of needing more water flow or higher velocity coolant flow through the engine. The engine is getting rid of the heat but the radiator is not. This is a symptom of needing more air flow through the radiator or a radiator with the ability to dissipate more heat to the atmosphere.
