I don't know. The Renault engines are quite a bit lighter. Imagine if they had fit some of the Gordini engines: 1800cc, 180-200hp, not shabby at all. Mind, at those output levels, they didn't last all that long nor could they be described as tractable. In the 140 range, though, they do last and are much more tractable than an equivalent TC. Of course there was also a twin cam, four valve Gordini engine as well. Or the turbo engine which put out 160 hp when detuned for the street!
Lotus TC engines were absolutely amazing, for their time. There was nothing else like them available for the price. They were a bit of a cobbled-up affair though and could have used beefier valve guides for a start.
