If I remember right I think the OP decided to go with 318 not posting to changes his mind, Just think this dyno of a 4.6l some of the info could be useful since we don't have much dyno info for 273 4.5l if anyone is thinking of doing a 273.
Similar displacement obviously but 4.6l ford has a smaller bore. Think you could get similar performance out of a 273 if built this way.
I think down the road I might do a magnum version of the 273 and put my valiant back to 273, think it would be a good performer especially with OD and deep gears, Swap to Magnum heads maybe with a beer barrel intake with mild porting and milling with zero decked quench. Mild roller cam around 265 with high lift and maybe 1.7 roller rockers.
