OPENED UP - The bottom of the B.R.M. V12 engine was opened for
the first time for inspection after McLaren had over-revved in practice.
The water pipe in the lower channel under the monocoque is the one that
was damaged by a kerb and eventually put McLaren out of the race.
Practice was on Friday and Saturday afternoons for four hours each day.
The times from the previous year, which were the target for this year,
were Surtees' fastest race lap of 1 min. 9.67 sec. (191.270 k.p.h.) and
Brabham's practice lap of 1 min. 8.42 sec. (194.843 k.p.h.).
At this time of the year in upper New York State the weather can be warm
summer or distinctly winter, and this year practice started under the
winter heading. A front stationary over the whole area closed airports
with low cloud, mist and rain. This caused some of the last-minute
arrivals from Europe to get stranded in New York City for the night and
make long, roundabout journeys to the Glen. At 2 p.m. as practice started
the weather was still bad and visibility ranged from a quarter of a mile
to 20 yards as the low cloud swirled over and poured off the hill on
which the circuit is situated and into the valley and over Lake Seneca.
McLaren and Amon were the first out and they felt their way round very
slowly. Ligier, Bonnier, Siffert, Clark and Surtees all went out in the
first hour and for some time Bonnier was quickest as he roared through
the swirling mist, but Surtees completed the first hour with a time of 1
min. 22 sec. During the second hour the rain stopped but the mist
persisted and both Brabhams and the Gurney stayed well away. Ickx came
out with the older Cooper, while the other with the 36-plug engine was
found to have a bad water leak at the front of the engine just behind the
bulkhead. This entailed half removing the engine to get at the leak and
kept the car away from practice. B.R.M.s also kept away while the weather
was at its worst and came out as conditions improved during the third
hour.
Brabham appeared as conditions improved but on his first lap a valve
broke and damaged the engine, so the car was wheeled away to have the
spare, an " old banger," fitted until the engine in transit from London
arrived in the early hours of race day. Rindt, unable to drive his own
car, put his number on Ickx's car and did a few laps' practice, getting
down to just under 1 min. 10 sec. before a rod broke, giving the Cooper
mechanics another 22-hour engine change. Clark was trying both his own
car and the one Solana was to use. In the latter he first got under 1
min. 10 sec. as it felt better on the drying track than his own car.
However, before the day was finished Clark was the only driver to get
down into the 1 min. 6 sec. bracket and Hill was the only driver to get
down into the 1 min. 7 sec. bracket, proving once again the performance
of the Lotus-Cosworth. Siffert stopped with suspected transmission
troubles but these proved to be only an unbalanced wheel. Solana didn't
get a drive on the first day, as is becoming the custom for the third
Lotus driver. The Honda, which finished up with a time of 1 min. 8.65
sec., was misfiring badly and came on to 12 cylinders only for short
bursts. When the Japanese mechanics got the car back to the technical
centre they stripped the complicated fuel injection system, cleaned it
and rerouted some of the pipes.
Saturday was fine with a few threatening clouds which never materialised.
All except Lotus and Matra were out when practice started at mid-day.
B.R.M. had some ultra wide wheels to take a Goodyear GT tyre with little
tread on the 12 in. of width that came in contact with the road. These
particular tyres are being used on the winning McLarens in the Group 7
racing and have 2-in. spacers in the mould to get the extra width. This
causes two small shoulders round the centre of the tyre which need
scrubbing off before the best adhesion is obtained. After several laps
Stewart changed the fronts back to conventional tyres, then he changed
the rears, and decided he preferred the handling of the normal tyres.
LISTENERS - As air from a compression bottle is put into the
cylinders of the B.R.M. V12 engine with the valves closed, the McLaren
mechanics listen for leaks at the inlet and exhaust ports after the
engine had been over-revved
Rindt had out the 36-plug Cooper but was not very happy as the brakes
were playing up and he did not like this at all, so after some time
bleeding and adjusting he handed the new car over to Ickx and went out in
the older car, which he threw around with his usual verve. Gurney was not
very happy with his engine and when he was on the back straight the whole
of the engine tightened up when the scavenge pump broke. McLaren was not
having a very happy day as the new limited slip differential was playing
up. On one part of the circuit there are a series of bumps which make the
rear wheels lift and as they do the differential momentarily freewheels,
which, with the engine near peak revs, could be disastrous. After
spending a lot of time in the garage McLaren rushed out in the last few
minutes of practice and was unable to lift off quickly enough to get the
revs down when it bounced without being cured. Although nothing came
through the side of the engine, 12,000+ revs did not do it any good.
Clark led the burst of speed in the last half of practice by going out
and getting a time of 1 min. 06.07 sec., the first lap at over 125 m.p.h.
and one full second faster than his nearest rival. Then with tanks full
he put in a time for himself of 1 min. 6.9 sec. Solana was allowed out in
the third Lotus now that Clark would not need it, and to every-ones
surprise, including his own, he got down to 1 min. 7.88 sec., seventh
fastest overall in only nine laps of practice, which either says a lot
for his improvement since last year or that the Lotus is an easier car to
drive than it looks. Brabham, Amon and Gurney, before his engine broke,
all got under 1 min. 7 sec. Then Hill went out for his final few laps and
thoroughly shook everyone by getting down to Clark's time, then getting a
bit faster and finally clipping a half-second off the best time to give
himself pole position and the 1,000 dollar prize with a time of 1 min.
05.48 sec. (203.501 k.p.h.).
This concluded practice and four teams were working hard at their engines
Gurney and McLaren to see what damage had been done; Brabham removing the
old engine and hoping the other would arrive in time; Surtees had a
metering unit break in the last run and this could have been the trouble
all along, so the mechanics were to attempt to take off the metering unit
from the spare engine and fit it.