Can I keep the stock dished pistons?

[MikeKC130J]

The 351w I’m building has stock dished pistons. Do I need to get flat top pistons? I’m planning on upgrading to some kind of power package from edelbrock, and going with the pro flo4.

 

[SteveL]

Depends on what heads and compression you want.

 

[MikeKC130J]

Depends on what heads and compression you want.

Looking for 9.5-1
I haven’t figured out if the Edelbrock Power Package will run with an EFi system. Have to wait until Tuesday to talk to tec support

 

[Broncobowsher]

I don't think you will get the desired compression with the disged.

 

[jckkys]

The combustion chamber and piston top were designed to work together. They produce the desired compression ratio and quench area while providing valve clearance. No dish may defeat some or all of these needed features. Sealed Power or other piston manufacturers would make what's needed if given the heads chosen and final compression ratio recommended by the cam maker. I would let them decide.

 

[blubuckaroo]

The combustion chamber and piston top were designed to work together. They produce the desired compression ratio and quench area while providing valve clearance. No dish may defeat some or all of these needed features. Sealed Power or other piston manufacturers would make what's needed if given the heads chosen and final compression ratio recommended by the cam maker. I would let them decide.

This is right.
The piston dish isn't just for lowering the compression.
Sometimes the dish in the piston is designed as part of the combustion chamber, and is needed for proper quench.
Higher compression pistons are made with the wrist pins at greater distance from the piston top.

 

[MikeKC130J]

Called edelbrock today and they recommended 60259 cylinder head
2182 camshaft. With the Pro-Flo 4 system. They said the power package was too aggressive for the bronco and makes its power mid range and top end. So have me the alternate part numbers. I better call them back and ask about dished pistons or not.