Explain this to me. I heard wacky talking about it and it brought up my curiosity, and searching only brings up a mighty 14 threads.

 

Thinking about a dowel pinned engine? Extra dowels are installed into an engine in specific areas in order to reduce torsional twisting of the engine under load.

 

Shot pinged I think is what it is called, the spelling is probably wrong though is that in any way related to chryo? Or maybe you are talking about pinned

 

he is correct. but its only necessary for a real race engine. thats spins high RPM's all day long.

 

A set screw will prevent the rotors from wobbling at high rpm.

 

I thought it was to secure the gear in the rotor better?

 

and that too. but again, there are other factors to keep the motor from blowing such as timing, high oil pressure and running it rich for those who loves high RPM.

 

High rpm engines can suffer from gear walk where the rotor gear starts to work it's way out of the rotor. To fix this the rotors can be machined to accept a large circlip which will retain the rotor gear.

 

^ +1

pinned rotors are just rotors with gears held in place by a circlip to keep the gear from "walking" at high RPM. obviously that would be a bad thing. however, it seems to be hard finding a place to do it other than shipping it out to the bigger outifts. i tried to get a pair done a couple years ago and couldn't find anyone to do it for me.

 

many builders wont do it as they want to salvage as much as they can if something happens. Im just one of them guys who doesnt give a **** if it blows. But again, my motor is a living proof that it helps.