Mark Sherman wrote:
>
> Dave Houser wrote:
> >
> > Mark,
> > Anyone have any
> > positive experiences regarding heat shields on T-series cars? Vapor
> > lock on hot days or heavy traffic still a minor problem.
> >
> > Regards,
> > Dave Houser
>
> Dave:
> I too would be interested in hearing of positive experiences with heat
>shields. My TD
> has a Marshall blower on it and can run extremely hotttt in July. I've seen
>plans for
> heat shields for stock 2-carb setups but it would take some creativity (and
>time) to
> adapt it to the 1-carb blower installation.
>
> Mark Sherman
In the course of my restoring T-Series motorcars, I always suggest to
customers that they have me install a heat shield for their T-Series
motors. I have had several customers complain they have vapour lock
problems. It is not always a minor irritation, however. It can be
potentially dangerous. One customer had stopped to re-fuel, and, having
done so, pulled out onto a busy road just to have the engine stop at a
most inconvenient time. Fortunately, he was not hit by the oncoming
traffic.
With the usual 2 carb set up of the XPAG type engines, there is
everylikelihood that petrol will be quickly boiled off from the carbs.
due to their position adjacent to the exhaust manifold, (the problem
being exascerbated by a hot day), and this will usually happen over
about a five to fifteen minute period, while the engine is idling or
stopped. The addition of a heat shield, made of aluminium and lined
with, dare I say it, ASBESTOS, has in all cases that I know of,
completely cured the problem.
I run a supercharged (Shorrock) TD, albeit without a heat shield. So
far, I have not had any problem with petrol evaporation, as the single
carb is mounted on the blower's extension manifold, and is further away
from the exhaust manifold than the standard set- up.
However, in order to increase the efficiency of the blower, I am
considering fabricating an additional air intake manifold to try to
enable the blower to ingest cooler air directly from outside the car,
rather than that which is being inhaled from inside the engine
compartment. Superchargers, by their very nature, increase the
temperature of the mixture being fed to the motor, and there by have a
somewhat negative effect, although, of course, the advantages far
outweigh the disadvantages.
Geoff Love, The English Connection
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