Hello, bumping an old thread but it's pretty inline with my question.
I'm unsure if my 1470 S1 engine has the correct pistons, as I haven't seen many pictures online differentiating the so-called high and low compression pistons the Renault 697 engines apparently came with. I'm used to high compression pistons having some extra material added on top in a pattern to clear the valves, plug, etc but I know they can also just be a normal, flat top that's higher than standard.
My engine is tagged as a 697-4 and the # (600) matches the VIN plate stamp. My pistons seem to have just a flat top, and there's some text and numbers on top that I can't figure out a meaning to. 76 is presumably the 76mm nominal bore, as expected. I don't see a reason for the pistons to have been replaced, two of them have a lot of small surface dents from debris and are due for replacement if anything.
Basically, I'm trying to figure out if this set is correct for my Europa engine:
https://www.renault16shop.com/Piston-and-liner-set-Lotus-Europe,-diameter-82,50,-76-mmThose pistons seem to have a raised section, and I don't want to doubly-add compression, if that's a thing (stroker crank? thinner block on the early Renault engines?)
Any info you have floating around is much appreciated!