396 pistons

[Willie496]

We are boring a 396 .060 over to a 408 using speed pro's #2242.
Our heads are 781 oval port with stock size street flow valves from manley.
Has anyone experienced pistons making contact with the heads?

The rotating assembly has been balanced.
Thanks,
Willie

[jerry clayton]

Where are they hitting??? You can't use open chamber pistons with closed chamber heads---that might be your conflict

[Willie496]

No these are closed chamber pistons in an open head (781)
I had someone say that even the closed chamber piston could be a problem on the exhaust valve side of the chamber.
I was just checking with other to see if they ever had this happen.
Thanks..

[pat mccarthy]

well you need to check it then you know ,not to sound like a smart a$$ but the close chamber piston 375 hp will smash in to the ex side of the O port heads that are closed chamber the 781 are open but the chamber still may need a small amout of a trim on the EX side of the head it needs to be check

[Willie496]

No problem thanks.
Willie.