Quote:
Originally Posted by Dave-ROR
They could make it pass emissions, however, it wasn't an efficient engine and with the gearing needed to delivery a quick car the fuel economy was shit. That's a bigger nail in the F20C/F22C coffin.
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The engine itself actually has about average to slightly better than average thermal efficiency in all BMEP ranges compared to other engines from the late 90s and early 2000s. The F20C is one of the few engines for which you can find a full BSFC chart and the numbers aren't bad.
There were several things making the S2000 perhaps a bit too thirsty by today's standards. One of course is that back in the day Japanese sports cars came with super short gearing, so there was not a proper highway gear (but this problem isn't limited to the S2k, basically every other car had very short gearing by today's standards).
Another is that the engine is not super torquey for the mass it had to pull (which is quite a lot for a 4 cylinder 2 seater), so the low gears have to be short as well, this is super bad for your EPA mpg testing, although I imagine manufacturers will start exercising the option to specify early shift points and this could be partially solved.
Finally, there's the horrible aerodynamics of the S2k, but that is also a problem not limited to the S2k.
If they really wanted to they could bring the F20C back but there's no car to put it in, it doesn't make financial sense to restart production and try to recertify it (which will need some modifications) when it's not competitive in any category other than power anymore.
One reason why super high rpm engines have gotten very rare that's not fuel economy related is that they're still trying to figure out how to achieve high flowing intake ports that play nice with direct injection at low speed, that also doesn't cost them a lot of money. Porsche has the "VTEC" style dual cams that lets them achieve this but even with that it's harder to do than it was with port injection. Honda still has VTEC but they'd rather use the extra lobe for a fuel-economy-mode, and 3-stage VTEC is probably cost prohibitive. Toyota has tried D4-S as we know but that is not enough to get you into the 8000+rpm range, and Subaru tried TVGs but that has the same restrictions. If you don't use a fancy valvetrain you end up with the BMW S65, which is not torquey and extremely thirsty.