In light of recent events, I must say that I am not trying to make the world
conform to my point of view but nonetheless , the following sentence was
posted today - 7/16/04 - and I have to disagree with it, and will explain
why after the sentence.
".......Combustion chamber shape (open vs. closed) has almost nothing to do
with
compression ratio....."
When you squeeze a volume of a gas ( meaning air not fuel ) into a space
that is smaller than it was before, it gets compressed to a higher pressure.
A given volume of air that exists in an open chamber cylinder head and then
compressed into a closed chamber head has to yield a higher compression .
If you look at the reverse, and take a dished piston and replace it with a
flat top piston or piston with a dome, does not the compression ratio
increase? You have decreased the space that a given volume of air has to be
squeezed into. If you went from a 86 cc cylinder head volume to a 74cc
volume, you have done the same thing.
If this is not the case, then the Mopar Performance B/RB Engine book is
incorrect, as well as most other engine build up and modification books as
well. I will defer to the mechanical engineers on this, as I may have not
used the correct terminology on what I am trying to say. Maybe combustion
chamber shape is not as good of a term as volume in this case ......can we
get a ruling, or did I misread this one entirely?
Mikey
62 Crown Coupe
( with larger chambered heads to drop the compression a bit and avoid pre
ignition and detonation on regular gas - or not? )
Back to the Home of the Forward Look Network