C91A6050 Canadian heads

[jimTN]

I have a C91A 6050 and C91A 6049 set of alum. heads. The appear to be the real thing, not USA made racing HC heads. Are the Canadian heads higher compression or 6.5 to 1.

 

[42merc]

Not high compression.
Standard low comp Ford.

 

[Kube]

I have a C91A 6050 and C91A 6049 set of alum. heads. The appear to be the real thing, not USA made racing HC heads. Are the Canadian heads higher compression or 6.5 to 1.

High compression heads had "AS" in the prefix.

 

[JSeery]

High compression heads had "AS" in the prefix.

Kube, are those what are sometimes referred to as "Denver" heads?

 

[scooder]

Yes AS heads were commonly referred to as Denver heads.
Martin.

 

[topfuel724]

Were the "AS" heads made in aluminum and steel?

 

[Bruce Lancaster]

AS heads are iron. The C in the PN designates Canadian manufacture...Some Canadian aluminum heads had slightly higher than irn CR's, probably just enough to compensate for the slight power loss. There is a Canadian service bulletin page listing CC's An CR ratings for nearly all USA and Canadian heads from about '32-49

 

[Kube]

AS heads are iron. The C in the PN designates Canadian manufacture...Some Canadian aluminum heads had slightly higher than irn CR's, probably just enough to compensate for the slight power loss. There is a Canadian service bulletin page listing CC's An CR ratings for nearly all USA and Canadian heads from about '32-49

Some AS heads were aluminium.
I have a set of 99AS heads, NOS, that are aluminum. According to the authentic documents that remain with this vehicle, they were were ordered (originally) to be installed on my '40 convertible (factory Merc. engine). It took me a LONG time to locate that set.

 

[Milt/Las Vegas]

I have a 40 convertible that has aluminum heads made in Canada with C7RA 6050 B.I was a ford partsman in the 60s and early 70s and understood that was an engineering number,C for decade 60 and 7 was the 7th year and 6049/6050 was the basic number cylinder heads.