A Trio!

[Alan]

Yes I’m sure he did

[dickie65]

Something in the back of my Pea Brain is telling me that some of the works cars had Bronze Heads.
Would they be marked as 9E though !!!

[Steve Jones]

I think Malcolm has one although that might not be a Raeburn. I recall it's VERY heavy!!

Steve

[Chris Garner]

Chris

Is the 65 head bronze or am i seeing things?

Charles

Charles,
My mistake I meant to say bronzED. By which I mean it is copper plated all over which I think was designed to help cooling. Whether it did is another matter.
It's been suggested that as it has the 9E1 cast into it it will be a Works item. I'm not so sure. I've never seen the patent number cast into one before, unless it's perhaps very early. Any ideas, anyone?

[dickie65]

The 9E just designates that its a Sports Item but does not mean its a works item.
I think 9C is Ulster. Charles P should be able to confirm this.
9E is EB65 / Nippy and likely to be found on the 75 parts.

[Alan]

The technical term is copperised. Not sure of the exact process but it’s supposed to be more durable than straightforward plating. The idea was to make the surface inside the cylinder more heat conductive to prevent local hotspots forming and so delaying pre-ignition. It wouldn’t make a deal of difference to overall heat transfer and cooling and I’m not sure if it helped much other than make you happy you had done something. Incidentally, don’t Google copperising. It seems to have a different meaning these days.

[Chris Garner]

It's encouraging to find that this posting has generated so much interest both on and off the Forum.

It has been suggested that the copperising process could have been carried out as early as 1937. Alan's comments on the benefits are sound but the coating would have worn off in the combustion chambers within days. None is present in the 65 head. 

Various reasons have been put forward for the Ricardo patent number being cast into the head. Both Austin and Ford used the Ricardo principle in their heads without permission. Ricardo was not too happy about this and Austin's entered into a dialogue with him. The Ford Motor Company ignored him!! It is possible that the inclusion of the patent number was a nod towards Ricardo's design.

Simon Thomas came back to me with a comment on the fact that from 1929 to 1931 all Works cars were required to have extra performance parts such as heads available. These are to be included in the current catalogue that was sent to the RAC with the race entry. This applied for scrutineering prior to the Double Twelve, Irish Grand Prix and TT. Simon does not believe copperised heads were ever thus.

Turning to the 9B head. These are exceedingly rare and even those familiar with Austin race engine know little of them. I am loathe to remove the head to ascertain the shape of the combustion chambers but it appears probable that the water ways are modified and increased to allow for better cooling.