A closed deck block design has a solid surface surrounding the tops of the
cylinder bores, something like a table-top with holes. In an open deck
design, the cylinders look more like free-standing tubes.
In the Chevy heads, the closed chamber design had much smaller combustion
chambers, leading to valve shrouding (and power loss). The open chamber
heads opened the combustion chamber up around the valves (the piston top was
enlarged to compensate for compression loss).
HTH,
-jerry
----- Original Message -----
From: "Jesus Villarreal" <jesvilla@gte.net>
To: "Bill Hamburgen 650-617-3329 FAX -3374" <billh@pa.dec.com>
Cc: <ba-autox@autox.team.net>
Sent: Thursday, May 03, 2001 12:24 PM
Subject: Re: "closed deck" vs. "open deck"?
> Bill Hamburgen 650-617-3329 FAX -3374 wrote:
> >
> > I've read about "closed desk" and "open deck" motors but can't find
> > a definition of what this means. Any takers? Thanks,
> >
> > /Bill
>
> How about "open chamber/closed chamber". This applies to the chevy big
> block combuston chamber on the heads. Early(65-68) 396-427 cu. in.
> motors were closed chamber design, later hi performance 427-454's were
> open chamber design.
>
> Jesus
|