Stroker, One thing about my own thinking. I can know a lot about one thing, but not a lot about everything. That gets us in a lot of trouble in our evaluating, etc.
What I have noted in limited involvement concerning the piston acting as a spring, was notable in thin wall engines. In that case, the skirt tails had again, a determined point of legnth for especially cold start. OEM style. This goes away back. As a piston transfers from cold to operating values, a piston transfers heat into mass, then out to min. mass, dissapating. The metal bridge limits that growth, the slots halt the expansion,around the pin bore on into the band. If it failed to accomplish this, sezure would occurr. @, a spring in tension. ---- On into the racing venue, early attempts in providing flexable forgings to satisfy those requirments were failiars. The cloverleaf did not fill the need, as it dissapated more heat into the band delivering diameter in the process. Relieving those high mass corners created additional issues in the piston, being forced into 'beyond tensile values' and they fractured. @ spring. It's an evolving process. In this day with thick wall blocks, artifically or meatalurgically, it has allowed the piston to evolve as we see it. Metals are probbably where they are because of the cold war being over. Yet, I still see with the pistons getting increasingly ridged, that spring effect dissappearing, all caused by metalurgy. Stregnth vs. stregnth. It must fit the application. Thin,thick,flexable,ridged. My oppinion. John Haskell
Aire Research Engr.
