Pretty good price for an 8 valve Rajo, if it's in reasonably good condition. Not as fast as the B model, but looks just as cool. Great speedster head. Will need high compression pistons to run its best.
So what would be a good piston choice?
I would use the high compression pistons available from the parts vendors. They don't work real well with flatheads as they create an inefficient combustion chamber. I have used them with good results in Rajo overheads. These old heads had low compression ratios for the same reason everything else did, low quality fuel. Raising the compression using the high dome pistons helps with modern gas to increase performance in lower RPM ranges. Beyond that, the higher volumetric efficiency of the overhead kicks in and you are going like a bat out of hell in a model T. A well built flathead will run right along an overhead until the overhead begins to really breathe. At that point you had better hang on for the ride. The thing is, overheads just look cool.
My old Sherman headed speedster topped out at 100 mph. The guy I sold it to has the speeding ticket to prove it!!!
BIG cam and 4 intake ports. Stromberg 94 carb. Counter weighted A pressure oiled crank