Most engine builders go to great lengths to "index" the intake and exhaust
manifolds so they line up perfectly. This would help the gases flow more
smoothly in and out of the engine. However, this brings up another
interesting point about using the Holbay setup; has anyone been able to find
the correct Holbay intake/exhaust gasket? I am planning to use a stock
alpine gasket but it does not line up. The problem is compounded by the
intake runner dowels that locate the gasket. This makes the middle two
intake port gasket holes much larger than the Holbay intake.
tom hill
-----Original Message-----
From: owner-alpines@autox.team.net
[mailto:owner-alpines@autox.team.net]On Behalf Of Carl Wade
Sent: Wednesday, May 14, 2003 11:06 PM
To: Alpine list members
Subject: SV: Holbay question
In my experience (marine engines) a step such as this would result in fuel
puddling at low speed, then a "rich bog" or something similar when the
operator accelerates.
One of the operations in increasing the performance of an outboard motor
is always to clean up any rough areas or "steps". This makes the flow of
intake/exhaust gases easier.
Think of it as the engine has to do less work just keeping itself running,
and
more of its output can be used for useful output, as opposed to the
"overhead" of keeping itself running.
I have seen this applied to such seemingly silly things as disconnecting
the
alternator output leads on large "pure stock" class outboard race engines.
The rules require the parts to be in place, but if the wires are broken or
disconnected, no rule violation. The alternator is then not using engine
output power for charging the battery. Obviously this is only used for the
standard 5-mile (3 lap) closed course heats, as opposed to the marathons.
This has got to translate into a miniscule amount of boat speed, but I've
been told that all those little details add up.
Carl Wade
Williamson, New York State, USA (near Lake Ontario)
B395000858 LRX
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