I can use any head gasket, but it must be a B18 head, and the maximum bore is only 85.4mm. We did enlarge the chambers to unshroud the 42mm intake valve, vs. the stock 40mm. I'm not sure the ports could, or should, be enlarged enough for a larger valve than that to make sense. The rules are pretty restrictive and they do check... I was only allowed to change the valves at all because the car was already bumped up a class for having front disk brakes.

I see the carbs and fuel octane as the main limitations, so the rest of the engine is tailored to work with those (and the budget, as is always the case). Also, the racer's "home" track is quite short with mostly tight turns, so having a wide powerband is a major requirement (we're using an 8 lb. flywheel, BTW).

We'll just have to see how it goes. The guy's been running two to four seconds a lap behind the leaders with the pretty dismal engine he's used for the past five years, so this one may be all he needs to catch them. If not, we'll make some changes for next season.