PD series Petter engines air cooled, with 3-1/2" bore and 4-1/3" stroke. Anybody seen one?
When looking through the Petter specs. Many share the common 4-1/3" stroke. Noting that the PH use a 3-7/16 bore and the PJ has a much larger 3-13/16 bore. With the PD being a little larger than the PH with 3-1/2".
The line of thinking is.........When in there anyways and boring. The PH sleeve while being thick walled won't take a 3-13/16" bore up from the 3-7/16". There is however plenty of sleeve wall thickness left if bored 3-1/2" and a PD piston used.
Any ideas if the PD engines shared the same piston pin and deck height as the AV,PH & PJ engines? Odds are they do as commonality reduces production costs.
I wish I could have found a PJ1W engine but the PH1W is all I have to work with. The generator project leaves the factory PH1W a couple of HP short. I'm hoping a little tuning and mild tinkering by cleaning up the ports and a little more displacement. This engine would be able to make 10+HP at 1800rpm without excessive smoke.
Of interest the PD engine with the 3-1/2" bore makes as much power as the PJ engines with the 3-13/16" bore? The PD is only 1/8" more bore than the 8HP PH series?
Did the PD engines have better flowing cylinder heads or where did the extra HP come from?