Kevin Sinclair

Building a 350 to go in an 84 Z28, are there advantages/disadvantages of flat vs dished pistons?

Thanks.
Kevin

Orr89RocZ

iTrader: (20)

Other than compression, flat tops may induce more turbulence as it approaches tdc during the compression stroke. This basically is like a big quench pad, this helps mix the air fuel and get a quicker faster burn. May be more desirable for power production/ efficiency vs a dish but not sure what difference it may be.

GeneralDisorder

iTrader: (1)

Basically they improve the quench if you have appropriately shaped chambers (such as Vortec style) with a large flat area that the piston can squeeze against. This better atomizes the fuel and generally helps prevent detonation. If you have bathtub chambers then there's not nearly as much benefit. Also all the force of the combustion is directed straight down vs some of the forces near the edge of the piston being directed at oblique angles with a dish. This is somewhat less efficient. Dished pistons are generally considered either smog equipment or for forced induction applications where a reduced compression ratio can't easily be accomplished by other means.

GD

Kevin Sinclair

Thanks for the replies. That helps..