Why did Mercury / Ford manufacture the aluminum heads for the 49-53 eab style block? I doubt it was cooling because they were manufactured in Canada. Was there a combustion chamber difference or higher compresion? Seems like I remember a matching aluminum intake for the 4 bolt teapot carburetor. When was that made and how plentiful are they? Thank you Jack
Both Ford 8BA and Mercury flatheads built in Canada had aluminum heads. The compression ratio for the Mercury head was higher when I compared it to a Ford head. Recently I changed the dome height on a set of those Mercury aluminum heads and the results were for the better seems the added head volume allowed the motor to run stronger and a bit cooler. I don't have any idea why Ford did that for the Canadian production heck all that did was cause us aluminum addicts another thing to search out for the collection!
When I was building my engine, I could not find a set of these aluminum heads so powder coated the set of Merc heads I had. About 9mos after getting the car registered, I found a NOS Mercury set locally. Go and figure. I was able to find an aluminum intake made for the Mercury carburetor and used it in the build. I have tried to research why they used Aluminum heads in Canada along with the intake manifolds and someone said there was a shortage of Iron in Canada after WWII and there was plentiful aluminum. Not sure -- but I have also heard that the Tappan Zee bridge in New York built after WWII was built with an intended shorter life span due to steel shortages at the time as well. I was also told these aluminum heads were called "cheater heads" as they may have had more compression and were able to be used in the stock car races at the time because they were "stock" They are in the process of replacing the Tappan Zee bridge now but I wasn't around before 1955 so can't say for sure but open to hearing what others have to say. Pete
I think Ford engineers were well aware of the advantages of aluminum heads but did not use them for cost reasons. In Canada, aluminum was cheaper because Canada was a leading producer of aluminum at the time. It takes a lot of electricity to refine aluminum, and Canada had the cheapest hydroelectric power. So, it could be the Canadian factory could justify it partly by lower cost aluminum, partly because aluminum is easier to cast, and partly because they made way fewer cars than the US factory.
I've read comments on here about flame propagation and combustion science, some were saying the iron head had more power since different temps were established. No question about weight advantages.
I think everyone knows aluminum heads have an advantage in efficiency. Thanks to better cooling, they allow higher compression to be used. This is why you buy aftermarket heads. A few stock cars in the flathead days offered aluminum heads, usually as an extra cost option. They were always higher compression and higher horsepower than the iron heads. Iron heads were cheaper and more durable which is why they were almost always used.
The term "cheater heads" is mostly in error.The REAL "cheater heads" are much more rare than the factory aluminum heads produced in Canada.Stock Ford cast iron had approx. 6.8 to one; Aluminum heads made in Canada were approx. 7.2 to 1 for a slight compression increase.The Canadian heads also had a Ford part number cast into them.The REAL "cheater heads" came about when WEIAND made a similar head that had the same Ford part number cast into them,but we're "cheaters" because they had an improved combustion chamber for some of the best flowing heads on the planet(this according to Joe Abbin,Roadrunner Eng,Alburquecke,New Mexico 335 h.p. Flathead)These "cheater heads" have the WEIAND logo on the inside of the water neck and are "invisible" unless the heads are off the engine. Cheater heads are not on every street corner like the Canadian heads are and the chambers are vastly different from each other.
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