Spark Plug Heat ranges, what gains have you made?

[Greg Reimer 7376]

In light of all this study of the laws of physics, what does the installation of an offset pin piston have on piston to valve clearance ? Sounds like a way to close up excessive clearance on one valve while opening it up on others. Or, like so many things out there, is it significant or just one more gnat to swat at?

[Stan Weiss]

Originally Posted by Greg Reimer 7376

In light of all this study of the laws of physics, what does the installation of an offset pin piston have on piston to valve clearance ? Sounds like a way to close up excessive clearance on one valve while opening it up on others. Or, like so many things out there, is it significant or just one more gnat to swat at?

Within a normal range of piston pin offset the piston travel curve does not change very much from centered. So if you are using piston TDC there should be almost no difference in VTP clearance because of wrist pin offset.


Stan


PS Above I am talking about if you degree the cam. If someone just installs the cam dot to dot (crank rod journal TDC?) There will be more of a change in VTP clearance from the offset over centered pin.


Stan

[MoJo Risen]

Originally Posted by Stan Weiss

Within a normal range of piston pin offset the piston travel curve does not change very much from centered. So if you are using piston TDC there should be almost no difference in VTP clearance because of wrist pin offset.

I believe it slows the piston down more at top of cylinder helping capture more usefule cylinder pressure. There are many different functional aspects of using offset Piston pins.

Stan


PS Above I am talking about if you degree the cam. If someone just installs the cam dot to dot (crank rod journal TDC?) There will be more of a change in VTP clearance from the offset over centered pin.


Stan

I believe it slows the piston down more at top of cylinder helping capture more usefule cylinder pressure. There are many different functional aspects of using offset Piston pins. Maybe this is a competition eliminator question since anything goes just as like STOCK Eliminator Piston pin offsets.