[Faster7]

I'm going to put together a Lotus 7 replica or similarly light RWD project car and am sorting through engine options. I'd prefer something that is relatively common (so newer than 1990.... newer than 2000 would be even better) and affordable. I'd entertain the idea of <60-80hp motors but am looking at some feasible 130-150hp options that would be much more entertaining.

I'd like to focus on gasoline engines right now, I know a VW TDI 3 / 4 cyl would meet all of my goals but unless I find a steal on one, it's going to take a long time to pay off. I also believe that CNG is something that I'll be able to use locally in the near future and I think once that crazy-cheap fuel cost is factored in, the diesel loses most of the advantages it has.

Whatever I pick, if necessary I'd run it on standalone EFI and have no problem adapting whatever motor it is to my RWD longitudinal transmission of choice.

I have Datsun 70's model A12/A15 motors and parts and could stick multiport injection on one, but don't think it's going to stretch the economy too much and will certainly not get past 80-90hp without adding a turbo... and replacement parts have gotten higher.
Suzuki/Geo Metro 3/4cyl are interesting but getting to be a bit long in the tooth.

Honda: L series, R series. Certainly getting cheap enough and spin the correct direction. Then I see that K motors have come way down in price and I know I could take the project in another direction by going gonzo power with one of those. So right now my favorite seems to be the R18, the simple Vtec on it and it's psuedo-atkinson cycle really seem promising.

Turbo Japan Kei car ~667cc engines could work, but USA availability is certainly an issue.

If there were more BSFC charts (one of the best collections I found was certainly here on the forum! Thanks!) I would have more to debate with but for now, I'm open to more thoughts and suggestions!