Stock header (looks to be about 2" from the exhaust port to the tuned-pipe inlet if the header were straightened-out), Novarossi EFRA-2601 high-RPM tuned pipe. (I had to buy the freaking thing from Austria; Novarossi USA never officially carried the one that fits my car.) The header is port-matched to the engine, something I took care of when I first built the car.

If increasing the compression further were going to produce any benefit, wouldn't I have seen at least a slight speed increase from advancing the ignition timing with the hot glowplug? I didn't see any change at all, at least not on the GPS speedo.

Would I see any benefit from replacing the steel crank bearings with ceramic? I have no problem doing that, I've replaced crank bearings with ceramic before to protect against rust, but I don't know if it would make any difference in terms of performance. It seems like all the popular racing engines use ceramic bearings nowadays, but maybe that's just a gimmick to sell more expensive engines.