I am planning on building up the b18c1: bore and resleeve, high compression pistons and port & polish. I'm not touching the cams right now. Any estimations on highway mileage with this setup? I do a-lot of traveling to SCCA events and I want to know what to expect.

 

I don't have an estimate for you, but the gas milage on a built 2.0 L would not be too much more than a similarily built 1.8 L.