A flathead -- with the intake in the block and the exhaust stacks out the top .
Waaay back when - some guy redid flathead Fords - using a reverse grind "Tucker " cam --which had the intake manifolds on the sides of the V8 and the exhaust stacks went out thru the ports originally used as the intake ports.
At least the exhaust did not heat the block.
I don't know how many of these were done but it was in the mid 1950's -
Much of the "new engin stuff goes back into the 1920's or earlier - About the only new design was the Wankle .
The ring a ding setup with the piston on the same plane as the crank and driving thru bevel gears is also an old -- but inefficient layout -
I ran a flathead Ford that really smoked (no pun)- and ran with the then new OHV Chev V8s- but truly efficient designs - have a way of rapidly moving to the front of the pack - that's why most of these other setups go by the wayside (as did my Ford)