On 10/05/2020 15:49, Weatherlawyer wrote:
On Saturday, 9 May 2020 16:22:34 UTC+1, John wrote:
On Sat, 09 May 2020 04:48:43 -0700, Weatherlawyer wrote:

How does the first Ford compare to the latest iteration, that is how
does the 1930's environmentalist compare to the 2020 version?


The original ford V8 engine was a side valve engine.

That's good to know. So how was the side valve replaced by a more efficient high compression engine?
And why?

Once the block casting was sorted it wasn't a big step to put push rods
where the valve stems were and and OHV head on, this would have given an
immediate increase in compression ratio as the empty space the valves
previously opened into could be eliminated, and the relationship between
thermal conversion to power is a straight line with compression ratio.

What I don't understand is what, other than higher engine speeds, the
advantage of overhead cams give in relation to thermal efficiency?