Re: Cylinder Heads

On Sun, 17 Feb 2008 08:19:15 -0500, Cliff <Clhuprich@xxxxxxx>
wrote:

On Fri, 15 Feb 2008 19:48:24 -0500 (EST), Black Dragon <bd@xxxxxxxxxxxxxx>
wrote:

We're looking at CCing the chambers for equal compression, nothing more.

Why? What's *wrong* with their design?
Engineers put lots of time & effort into that.
I'd expect that *almost* anything you could do would make maters worse.
The "almost" does not include a few things that require lots of skilled
time-consuming hand labor that machines do not yet do well.
=====================
Successful engineering is successful compromise.

"Power" is only one consideration among many in engine
design/development . Emissions, producibility, and
longivity/durability are a few of the many other design criteria.

The engine developer is simply rearranging the designers
priorities, generally trading a gain in one area for a reduction
in another.

By porting the heads, "power" is increased (and indeed most
likely is increased only in a selected rpm range) but the other
characteristics such as emissions and durability (and
smooth-smooth-smooth idle) are reduced. Other modifications may
also be required such as a high lift -- extended duration cam.
It is entirely possible that a ported head intended for high rpm
operation would produced less, not more power with a stock cam
shaft and intake manifold at normal street RPM.


Unka' George [George McDuffee]
-------------------------------------------
He that will not apply new remedies,
must expect new evils:
for Time is the greatest innovator: and
if Time, of course, alter things to the worse,
and wisdom and counsel shall not alter them to the better,
what shall be the end?

Francis Bacon (1561-1626), English philosopher, essayist, statesman.
Essays, "Of Innovations" (1597-1625).
.

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