I am absolutly positive you could put a s2000 engine in a lotus super 7 kit. I actually have a lotus 7 kit car im looking to sell, the only problem i think youre going to run into is that the car i have has mazda running gears and drive train because it had the rx7 rotary engine in it, but im not positive that the s2000 and rotary engine spin in the same direction, i believe the mazda is counter clockwise while the s2000 is clockwise. but it would be a sweet ride with a hott s2000 engine in it, because the car weighs next to nothing 1700 lbs. You get the idea. it would be a corvette killer on the street