At one time I ran around in a '66 Dart 270 hardtop with a 318 dressed as a HP 273. At the time I couldn't find high compression pistons for the 273 short block I had or even closed chamber 273 heads for a decent price. So I built a 318 with KB pistons at zero deck and used the '302 casting closed chamber 318 heads. Ran the '66-'67 style single plane cast iron 4bbl intake with an adapter to fit my 390 CFM Holley. The cam was just a little hotter than the original HP 273 cam. It idled well and made lots of low end torque. With 3.55 gears and a 4-speed it ran 14.6s. Stock iron exhaust manifolds and all.
I have an almost fully dressed HP 273 on the stand right now. It doesn't have any of the HP 273 dress-up stuff, but it does have stock style high compression forged pistons, a big hydraulic cam and a trick rear sump oil pan. I polished the pistons to retard carbon buildup. I should probably show this project some love, but I have others that also need attention.
