Casting numbers on the TC heads

[cal44]

I posted over on Elan.net this question.  Thought I would cover all bases. 
Is there a way to identify when the TC heads were made by the casting numbers?  I have not been able to find (so far) a guide for the castings.

Mike

[EuropaTC]

I'm not aware of anything Mike. In the Miles Wilkins book he says that there were letters stamped on the boss by #1 plug from 1968 onwards and gives the H,N or S as the typical identification, which seems to be more to do with the intended duty rather than the date of production. For example "N" heads were produced in 1970 and 72 onwards with "S" heads between 70-71.

Typical Lotus really, make it up as you go along 

As an aside, why do you want to know the age of the casting anyway ?

Brian

[cal44]

Brian,

I spent decades with the numbers matching crowd (Porsches, Boss 302s, Sunbeam Tigers
and a few "dreaded Corvettes..ugh").........old habits.  This is nice not having to think about numbers other than the block stamping.  Even then I wonder how many blocks are original to the cars.

Thanks for the info.

Mike

[EuropaTC]

I remembered later on yesterday that there's another difference which they called Mk1 & Mk2 heads. The bucket/followers over the valve springs that the cams move, these ran in the bare aluminium of the head in the Mk1 heads. They later changed this in the Mk2 heads to having a sleeve insert around the buckets, presumably to reduce wear on the casting. I don't know the date of this move but I'd guess it was in the mid to late 60s.

Corvettes, now what's wrong with them ?  My uncle (Rockford, Illinois) is a real petrolhead and had a metallic blue one for a while, and as a young lad growing up in England where most cars were dull & boring, I thought it looked great.  Now I'm (supposedly) grown up I still like the style of the 70s 'vettes, whenever I see one at shows it just shouts "American" at me.

Brian

[cal44]

Brian,

I'll send a PM..........don't want to hurt anyone's feelings if they own one.