Thanks to all that responded to this issue. I found the online examination
of under the hood temperatures and on top of the hood pressures to be
informative and somewhat surprising. I thought it would be hotter on top of
the
engine. Any of you who live in the winter zones know that the engine image
appears
on the frost of the hood first.
Reference for hood opening study again is _
http://www.oman4x4.com/hoodvents.htm#theory_
(http://www.oman4x4.com/hoodvents.htm#theory) .
His choice of louvers is probably not vintage legal, (although I do like
the idea that you can seal off the louvers). The shape of the louvers chosen
raised additional question in my mind about the most effective size opening,
shape of the opening, and positioning (these seem to be on an angle on the
hood), He really did not study that louver design and its not clear that the
choice had anything to do with GM engineering of the louvers for effectiveness.
Most of the louvers that I have seen on vintage race cars are narrow,
closely spaced, and varying in the angle of the sheet metal bend (although
mostly facing mostly backward rather than upward). What remains in my memory
of
fluid flow dynamics suggests that one would want larger openings than the
narrow slots than I have seen on many vintage cars and one would assume that
the
air flow should be directed as vertically as possible, but most of sheet
metal openings (if my memory is correct) are mostly directed backwards. In
addition, at speed there would likely be some turbulent air flow through the
louvers that I would think be best managed by spacing and upward air flow away
from
the flow from the next louver.
What am I missing here?
Cary
|