I have been watching this thread and think that one of my experiences
might be of interest. I purchased a new TR-4 in Oct. 1963. One of my
friends was an oil additive salesman for Monsanto. He described the
break in procedure they used for their test engines to me and I decided
to follow it. I went out on the expressway in Pittsburg, for 100 miles
I accelerated at 3/4 throttle from 35 miles per hour to 45 mph, I then
coasted at trailing throttle back to 35 mph, and repeated the process
again and again. For the next 100 miles I repeated the process from 45
to 55, then for the third 100 miles I repeated the process from 55 to
65. For the next 200 miles I stuck with the 55 to 65 mph interval to
avoid tickets and went to full throttle acceleration. This took four
evenings, but I didn't mind I was anxious to get the car ready for some
throttle bashing. I then had the oil changed at the dealer, he used
Wolfs Head, I always used Ouaker State High Detergent Multi grade after
that. I was never hard on the car, but I was always ready to
participate in an impromptue drag with the ocassional American car
driver that thought i was driving a roller skate.
The engine is still running strong, and does not burn oil after 35
years. The only new internal parts are a timing chain, woodruff key,
and chain tensioner which I replaced, at the suggestion of Cox and
Buckles, when I put the engine in my TR-3A in 1986.
Soon after the break in I was making a continuous high speed, 65 mph,
run up to the North side of town when I noticed that my 80-85 psi oil
pressure dropping to 20-30 psi. When I would slow to about 40 the
pressure would gradually increase. I stopped to check the oil and
noticed oil foam on the dip stick. I drove slower and took the car to
the TR dealer (A&L Motors) the next day. They told me that the oil was
foaming at the high pressures being developed by the oil pump, and that
they would have to shim the pump for a lower pressure. I okayed the
work, under warranty, and I never had another problem. The engine still
produces oil pressures of 60 psi at speed and 40 psi at idle. I have
never seen the 80-85 psi reading again.
As an aside us American hot rodders obtain high volume oil pumps vice
high pressure oil pumps when we are building a hot engine.
Understanding the relationship between volume and pressure, volume is
the most important for long bearing life.
Cheers, Don J. Howard
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