I bought a Project Prelude, and just pulled the engine today... I am completely rebuilding the entire engine, and the engine that came with the car had 176,000 miles on it. I live right next to a machine shop that my grandfather use to own, so I get all sorts of free work and major discounts which is awesome as hell. According the 6 guys that work their, and have rebuilt engines for 25+ years mileage it won't matter if you do end up rebuilding just about everything. Which I am doing... Everything from the valve-train down to the crankshaft are being replaced. Fun, fun, fun... And pricey, pricey, pricey...