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This thread is a continuation from another that started going off-topic, hence the reason why I am continuing it here. If you missed it, here's the link to what's been said so far:
http://www.turbododge.com/forums/showthread.php?p=680656#post680656
Basically, this is a discussion of the reciprocating geometries of an engine and how it factors into HP production.
Bore to stroke ratio.... rod ratio.... piston acceleration... piston surface feet per minute (how far it actually travels up and down the bore per rpm) mean piston speed (kinda the same thing). This all greatly affects HP production. Our engines peak at well under 6k rpms, and some 16v 2.2's will peak under 6,500rpms. As we all know the 16v heads flow a great deal more than the lowly 8valver's, yet peak HP moves up the scale only a tad. This has alot to do with what this subject is all about. Geometries... not really about using lighter pistons and rods to achieve a higher peak HP.
Think to yourself about how much harder it is for the piston on *our* 2.5's vs. 2.2's to accelerate and decellerate in the same timeframe due to a less than desireable rod ratio. Add in a long stroke and the piston has to run a faster SFM (surface feet per minute) for each stroke.
Hope this thread turns into a good discussion!
http://www.turbododge.com/forums/showthread.php?p=680656#post680656
Basically, this is a discussion of the reciprocating geometries of an engine and how it factors into HP production.
Bore to stroke ratio.... rod ratio.... piston acceleration... piston surface feet per minute (how far it actually travels up and down the bore per rpm) mean piston speed (kinda the same thing). This all greatly affects HP production. Our engines peak at well under 6k rpms, and some 16v 2.2's will peak under 6,500rpms. As we all know the 16v heads flow a great deal more than the lowly 8valver's, yet peak HP moves up the scale only a tad. This has alot to do with what this subject is all about. Geometries... not really about using lighter pistons and rods to achieve a higher peak HP.
Think to yourself about how much harder it is for the piston on *our* 2.5's vs. 2.2's to accelerate and decellerate in the same timeframe due to a less than desireable rod ratio. Add in a long stroke and the piston has to run a faster SFM (surface feet per minute) for each stroke.
Hope this thread turns into a good discussion!