CHEV 216 VS Chev 235

[Jordan Baker]

Thanks Phil and all for all your help.

I'm seriously looking into making an adaptor plate for the early one hole pump to mount to the two hole block. It's frustrating as the throttle linkages all line up perfectly when the one hole pump is used.

I played around with some paper this morning using theo one hole backing plate as he basic pattern. I then overlayed the two hole plate and traced out the two holes. The blue is the holes in the block. The green is where the frost plug is located. The yellow is the original one hole pump hole as found on its backing plate. The cutout portion of the paper is what I'm proposing to remove from the block to give the same amount of flow.

Concerns I have and I have a few.

Obviously drilling into a block and removing material is worrisome. The two small blue circles are the original threaded holes. On the inside of the casting they are solid. If I were to screw in some small set screws would that help make it more solid? On my drawing the two lower red circles are where new holes would have to be drilled and threaded to mount the lower water pump bolts. When I've read over the 235/261 adaptor plate instructions they have you drill new holes.

Thoughts?