Dear Vintage Race List,
I have a technical question I hope some of you on the list can help me with.
I am racing a 1964 MGB with CSRG in northern Calivornia. Even with a new
crank and bearings in my 3-main engine, I am getting serious blow by and
enough pressure in the crankcase that I lost nearly a quart of oil out the
rear main after the last race weekend. This leakage took place mostly in
the
paddock area after my race. This engine leaks little under normal
conditions
and the rings are tight. When I drove it on the street (last year) it never
used oil. I am also noticing that others in my group with MGBs (even the
5-main engines that have a rear main oil seal) pump out a good quanitity of
oil after a race.
I think the cure for this condition is what A. Graham Bell describes in his
book" Four-stroke Performance Tuning as a evacuator breather system. I
bought the device and it is simply a piece of 1/2" black plumbing pipe cut
on
a angle with a one way valve on the end. The theory is that you weld this
pipe into your header and connect it to the valve cover. The flow of
exhaust
gas over the angled pipe creates a vacuume of about -5lbs and exhausts blow
by pressure in the sump into the header.
My questions are:
1. The 1/2" black pipe looks like it would work fine in the headers of a V-8
engine, but in the dmall diameter pipe of my header, it looks like it might
be
more of an obstruction to exhaust flow. Any thought on this issue?
2. The regulations for the group I race with call for "two separate catch
tanks, each one quart capacity required for the engine and for the coolant
system. They must be securely mounted and easily accessible for checking
and
emptying". I was thinking of using a metal one quart can (brake fluid can)
which I would weld in a metal pipe that could attach to the crankcase
evacuatior and have the hoses I now have from the tappet cover and rocker
cover attach to the top of the metal can thus providing a vacuum on the
sump.
I would also need a breather on the rocker cover to let air in. Would CSRG
accepth this setup? I realize that this is a question for local members.
I would appreciate any dialog on this from anyone "who has been there and
done
that".
Regards,
Rod Schweiger
'64 MGB Sebring Replica #119
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