Okay, so I've been pricing out marine engines. I've read a lot about how full dished pistons suck.
Just to be clear, the GM F/D piston (especially in the Marine SBC) creates a place for the flame front to hide during combustion.
This can and will cause "detonation" under the right conditions.
But it seems all new GM marine engines come standard with them.
In the Marine build, yes!
As I've said many times..... the GM engineers would like to use the proper pistons in this SBC Marine version. However, the bean counters won!
With the GM F/D pistons, one part number fits all 8 bores.
The guys installing the pistons/rods combo can be drinking a cocktail or smoking pot while doing so.
The guys installing the pistons/rods into the cylinder block can also be drinking a cocktail or smoking pot while doing so.
How can I find a marine engine with d dished pistons?
If you mean a factory GM:
......with a D dished piston, you'd need to purchase a GM SBC in a Pre-Vortec higher performance engine, perhaps Corvette or Camero or similar.
......with a LCQ piston, you'd need to purchase a GM SBC in the Vortec version, and again in the higher performance engine, perhaps Corvette or Camero or similar.
However, the static compression ratio in either build will be too high for Marine use.
I wanted new, but is there a reputable rebuilder that uses the d dished?
You can find reputable engine builders that can do a proper Marine build for you.
Keep in mind that:
..... the D dished piston would be used underneath the Pre-Vortec cylinder heads.
..... the LCQ (low compression quench) style piston would be used underneath the Vortec cylinder heads.
The dish volume (of which will be selected) with either piston will determine your S C/R.
If you go with valve reliefs that match the valve diameters, you will need 4 part numbers.
The guys installing these pistons cannot be drinking or smoking pot!
The target will be a quench dimension of approx .038" for a 5.7L build, and approx .045" for a 6.2L or 6.3L build. (higher for HP Street use)
The Marine quench dimension will be less than that of the HP Auto build!
NOTE: the only things that require special attention will be:
... the piston's dish volume as per bore/stroke and combustion chamber volume.
... the piston orientation in each bore.
... the piston deck height.
....the compressed head gasket thickness.
Nothing else to the build needs to be changed.
Depending on the piston material (cast aluminum, hypereutectic or forged) the added cost should not exceed several hundred dollars.