found this article saying quote "Building an inexpensive high horsepower 273 is quite a story. I have one built and ready to go for next race season. two years ago, I switched from a factory headed 273 to a W2 headed 318. The 273 was 11.04:1 and had a CompCam292 hydrolic with solid lifters. It ran a best of 12.36 @109 in the 1/4. The 318 has 9.8:1 and a MP .541" lift circle track cam and just ran a 11.26 @119 a few weeks ago. The 318 has quite a bit more horsepower still to be found, but that will have to be looked for later as the 273 is being put back in very soon.
This 273 is a true 11.0:1 assembly with factory 273 heads modified with my porting work and cut down 1.92/1.60 Chevy +.150" long valves installed. The cam is a MP circle track grind with .528" lift. The pistons are an old set of Jahn's cast that stick out of the hole .230" at the dome. Regular iron rings are all I could find, much less afford. The engine has the regular trustworthy 8553 Felpro head gasket. The intake manifold is a Chrysler marine item that is very similar to the original 273 4bbl unit. It did require some coolant flow modifications in order to work on the 273 with a regular automotive water pump. With the same AFB Double Pumper carb that I used on the previous 273 build, I expect to see time slips in the 11.80 range in my 3281 pound Dart.
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