Lotus Elan and Lotus Elan Plus 2 Forums

I've currently got three Lotus T/C cylinder heads with no number below the core plug on the rear face which is unusual - I guess they didn't originate from Elans (or any Fords).
One of them has a 7 digit number stamped to the side of the core plug 9966##1 - does anybody recognise this format? It's definitely a racing cylinder head, maybe a Vegantune number?

Did some racing Elans have engines supplied without any engine numbers IE if the head was bought as a spare part from Lotus (or Ford)?

Go!!

Hi, I offer this as a possibly plausible theory based on some heads I have seen; I suspect that type of head marking could denote an engine used for internal testing and development purposes. I have seen the odd head, with some "developmental" modifications that are marked this way, and if I recall I have one marked in a similar way on my shelf at present.

Thanks for your response. I think I've found out what one of them is - I believe it's a racing fuel injection head as the casting isn't a typical Lotus casting, it's got some added "cast-in" bits here and there for the fuel injection pump at the front of the head (as opposed to it being mounted off the rear of the head as is the usual case)

Of the other two heads one is a new old stock head so never made it into a car, the other one I'm not too sure about but it came with a Lotus block that also doesn't have any numbers stamped on it. The mystery continues!

One the backs of heads I have seen two types of systematic numbers

On early heads up to around S3 introduction the engine number was on the rear of the head ( usually)
On later heads the was usually a two letter and two numerals number ( such as CG21) which looks like some sort of batch code or date code

However in true Lotus tradition I have also seen heads with no numbers and heads with other random numbers. The other random numbers may relate to stamping by workshops doing work on the heads to track them and relate them to a customer job

cheers
Rohan