Lotus - 35 I think - with Martin V8. An F1 car but never, as far as I'm aware, run in an F1 race. Charles Lucas' name crops up, as does that of Piers Courage.
Well done, Willie! That's what it is - I'm sorry for the poor photo but there are very few period images. It only ran a couple of times, I think in Formula Libre, driven by Roy Pike and, as you say, Piers Courage. It was built at a time when Charles Lucas was running a very successful F3 team, and was probably an optimistic attempt to go upmarket.
I think the car ran recently at Goodwood ( members meeting?) although it's probably a lot more reliable now than it would have been in 1967. I've seen it referred to as a Lucas-Martin but I reckon he didn't alter the chassis muich at all so as far as I'm concerned it's a Lotus.