I am restoring a '65 Dart 273, 2-barrel that sat for years. I will eventually need to re-ring and get a valve job. My question is where to get a gasket kit with correct head gaskets. I see many gasket kits like "Victor FS3536" that state for 273-360 engines. Many say 273 for 1966+ only. Is this due to the different intake manifold hole angle?
Using a gasket with 4"D bores on a 273 engine with 3.625"D bore and an installed thickness of 0.02", adds ~0.05 in^3 or 0.8 cc. This lowers compression ratio ~1%, which is negligible (one post claimed to 7.5). However, it adds quench area which can increase HC emissions and lower efficiency, and could cause carbon buildup. In any event, over-sized bores look dumb. Does anyone have experience using these over-size gaskets? Is there anywhere to buy correct ones?
Not an immediate concern since I decided to leave the heads on since I measure acceptable compression in 6 cylinders (140-150 psi) and tolerable in two (120, 125 psi). Some that previously tested low have gotten better over weeks from oiling and turning the crank, so maybe just stuck rings. I will re-check after driving a while. No info on history since bought from a tow yard. For now, I am just replacing the timing set and externals, including aluminum intake (redrill holes). I have a Holley Projection w/ O2 feedback for fuel and Crane Cams XR700 optical ignition, as used for years on my '65 Newport. Will post more on the restore later.