the 307s can be used in the 250 blocks same as for the 283 pistons in the 230 blocks. As for turning the Pin Don't If the pistons have a snap ring groove in them Just have the rods floated. Now depending on the skirts on the 307s in some cases the skirts need to be trimmed to clear the crank. I have ran TRW 307s for 17 yrs now on the same set of pop ups. I had to have the tops cut for valve clearance and the skirts needed crank clearance. Those 307s should bring you about the same compression as listed on that site if you match the same head CCs And have the block decked. and I think you'd be a happy camper. hope this helps.}[oooooo]
ps i know of a few guys that run the stock type 4valve releaf 307s and have been very happy with their settups.
God doesn't like ugly.
