Equations of Motion -
Adventure, Risk and Innovation
An excerpt from Chapter 17 - Four-Wheel Drive
Mt. Equinox Hill Climb, May 22, 1950
Mt. Equinox was a vindication of all our expectations for the FWD Miller. We won and set a record. The event was best described in my letter to Don Olen [at the time, director of engineering for the Four Wheel Drive Auto Company], as transcribed in full, which also relates my hope that FWD would finance a more suitable transmission and brakes for road racing. Our success in this hill climb seemed to confirm the potential of four-wheel drive under traction-limiting conditions.
29 May 1950
Mr. Donald B. Olen
Subject: Resumé of Mt. Equinox Hill Climb
Dear Mr. Olen:
Needless to say, it is with considerable pleasure that the following report on our experiences with the FWD at Mt. Equinox is presented. The success in this hill climb would seem to culminate one phase of a mutual endeavor whose objective has been to demonstrate that the FWD Special in its present form, and without appreciable modification for hill climbing, or road racing, is still by virtue of its four-wheel drive superior to the conventional rear-drive cars. While the performance times speak for themselves, I would like to emphasize, in addition, that the basically excellent handling characteristics of the Four Wheel Drive were markedly demonstrated in the present event.
For some time the Sports Car Club of America has been attempting to obtain the use of a hill climb site in the east which would be in many respects comparable to Pikes Peak. All postwar attempts at obtaining the use of the Mt. Washington Toll Road had failed, and attention was focused on the relatively new Equinox Sky Line Drive which ascends Mt. Equinox, located at Manchester, Vermont. This venue turns out to be superior to Mt. Washington, and now is the outstanding speed hill climb site in the east. While the total distance run is about one-half of that at Pikes Peak, the average grade and the maximum grade encountered are approximately 30% greater than that of Pikes Peak. The number of turns per mile, and types of turns, are very similar to Pikes Peak, and the road surface and road width are comparable. In general the ?hill? comprises two peaks, namely Little Equinox, which is 2,720 ft. above the base, and Big Equinox, the summit, which is some 496 ft. in elevation above Little Equinox. There are two pronounced groups of switchbacks and hairpin turns, one of which occurs below the summit of Little Equinox, and the other relatively short of the summit of Big Equinox. The initial portion of the road between the two peaks runs along an exposed ridge and has a pronounced dip in it. From the driver's point of view, the most hazardous point on the course is that section just at the top of Little Equinox and down onto the ridge. The approach to the summit of Little Equinox is steep, but fast, and since the trees stop just short of the summit, there is no way of judging the exact direction of the road as one comes up, over and down onto the exposed ridge.
On the day of the climb, the weather was beautiful and the road surface was dry. No work had been done on the surface since the winter, but with the exception of the section along the ridge, it was quite smooth.
The Event-On the day preceding the hill climb, some time trials were run on a very rough backwoods road circuit of about five miles in circumference. These preliminaries gave a further opportunity for tuning the car.
The Mt. Equinox Climb was organized in the following manner: Three climbs, if desired, were permitted each entrant-the first climb being purely for practice, and was untimed. A standing start at the Toll House was used throughout, the driver being given two warning counts, and then the flag. Timing was accomplished by two-way radio between the Start and Finish. As will be noted in the summary of results, the entrants were divided into the standard SCCA categories and displacement classes. In addition, the Fastest-Time-of-the-Day, irrespective of category and class, was recognized as the record for this ascent.
As will be noted, the FWD competed in the Unrestricted Category, operating without full road equipment as required by the Sports Category. It so happened that the first three finishers in the Unrestricted Category were also all in Class C (which is defined by engine displacement limits, whether the car is supercharged or not).
It was, however, apparent from previous experience that the primary competition was to be expected from Weaver in his Grand Prix type Maserati. This machine is similar in many respects to the car in which Unser currently holds the Pikes Peak record. Table 19-2 compares the FWD and the Maserati.
An examination of the table serves to show that with the exception of drive type, the Maserati has everything in its favor, including a 50% higher power/weight ratio. In addition the car is equipped with a single-seat body with excellent vision of the front wheels so desirable in hill climbing, and has a much more suitable transmission, brakes and suspension, for this type of work. The Maserati was designed for road racing and is newer than the FWD Special. It will be remembered that this Maserati driven by George Weaver won the Seneca Cup Race at Watkins Glen last year, and though dogged with mechanical trouble, is one of the outstanding machines in the Club.
The FWD was selected by draw as the first car to make a timed ascent. Without any previous mark to shoot for, and in an essentially conservative manner, this run was made in 7 min. 24 sec. or an average of nearly 52 mph. This run was normal in all respects, except that with the relatively high tire pressures (25# all around) it was noted that it was possible to spin all four wheels on the softer corners, when operating in low gear. It was, however, felt that the technique used on the hairpin turns was not correct, and that the car had been allowed to drift too far to the outside. A different and more satisfactory technique was tried on the subsequent runs.
After several other cars had completed the climb, including the two Jaguars, Weaver made his ascent, and recorded a time of 7 min. 8 sec. or some 16 sec. faster than the FWD. This was a well-executed run and, as Weaver later described, his main problem was that of minimizing wheel spin, particularly on the hairpin turns. His statement of the rear-drive performance on the loose hairpin turns coincided exactly with our observations of the high-powered rear drives at Pike' Peak, namely that the cars lose momentum and nearly come to a stop as the wheels dig in. In this respect both the Jaguar drivers (Spear and Cunningham) and Weaver stated that it was better to operate in a higher gear (thus losing the high power associated with more rpm) and avoid wheelspin as much as possible. Incidentally, Weaver was operating with 19?20 lbs. rear tire pressure, and hence was probably achieving optimum traction. There was never any question on the Maserati of power limitation, so the increased rolling resistance of the tires at low pressure could not have been influential.
Before making our second run with the FWD, tire pressures were reduced as previously indicated, and a new set of tires installed on the rear wheels. Since this run did not take place till some time after the one described, it was necessary to carefully warm up the engine before proceeding to the starting line.
With the four-wheel drive and the FWD's power there is very little problem in making a clean getaway from a standing start. On this final run it was decided to take full advantage of everything the four-wheel drive has to offer, and the engine was revved up to about 5,000 rpm before letting the clutch pedal out; as the clutch was engaged, the throttle was pushed hard down, and for an instant there was momentary wheel spin after which the machine literally ?took off.? Wilcox, who was standing aft of the machine, described the start as spectacular in the extreme, and further noted that the machine accelerated in a perfectly straight line with no apparent fish-tailing. The rev limit in low gear was reached very shortly and the car was shifted into second before the first turn, through which it continued to accelerate. Because of the lower tire pressures, and also because of the lower pressure in the rear tires in relation to the front, the car did not have as nice a feel as during the first run. Nevertheless, it was perfectly controllable and the traction was improved.
The technique used on the hairpins on this run-an improvement over that of the preceding run-was as follows: The car was brought into the turn well on the outside and then rather sharply cut directly across the inside of the apex of the turn in an almost straight line, and thence to the outside of the road at the exit from the turn. It had the disadvantage of going through the middle of the loose dirt on the inside of the turn, but had the great advantage that there was never any question of sliding off the outside or having to decelerate in the middle of the corner. The impression was gained that the car was either accelerating slightly or maintaining a constant speed on all corners.
One especially bad slide was experienced when the car was brought into the sharp corner preceeding the first set of switchbacks. The approach to the corner had been made much too fast, and heavy braking was resorted to, which with the left rear locking up, threw the car into an incipient spin. A substantial burst of power straightened the machine out. (On a rear drive it would have been necessary to remove power, and hence lose time.)
Anticipating the fast stretch along the ridge, the summit of Little Equinox was approached in high gear at 70-odd miles per hour. Needless to say, the sensation of coming up over this rise and out onto the ridge with nothing but blue sky ahead is one that will not soon be forgotten! Along the ridge the speed was limited entirely by the characteristics of the suspension. This ridge is the roughest section of the course and with the FWD's suspension, the driving problem reduced itself to maintaining the car within the boundaries of the road.
Before reaching the last set of switchbacks and hairpins, a shift to second gear was made, and as on all down-shifts, double clutching was used. On this occasion, the moment the lever was placed in second position a terrific chatter set up and the car did not appear to respond to the throttle. It was apparent that something drastic had happened to the second gear, and that it was probably stripped. The writer had no impression of encountering any difficulty in throwing the lever into second, or any impression that the box was being maltreated; however, it is entirely possible that the fault may lie with the driver. The lever was immediately placed in third gear and an attempt made to accelerate. The lever was then placed in first gear and the remainder of the climb made in this ratio. Fortunately, because of the hairpins and the relatively sort distance beyond them to the top, this was not too adverse a handicap, but it is believed that it must have lost us several seconds. In the final run to the finish line, the engine rpm momentarily hit 6,800, which is a speed of some 65 mph. This calculates to a piston speed of about 5,000 ft./min. which is extremely high for even a short burst. If the engine power curve continued linearly, this rpm would represent a bhp output of some 260.
To complete the story of the climb it should be mentioned that the safety belt had become unfastened just over the summit of Little Equinox and whenever second gear was used (on all climbs) it was necessary to hold the lever in place with one hand, which means that at least one-half of each climb was made with only one hand on the wheel.
Table 19-3 presents the Mt. Equinox Hill Climb results. Handicapped though it may be, the FWD has fairly beaten the rear drives under circumstances where everything was in their favor.
If any further evidence of the superiority of this drive type is needed, a comparison between the FWD's performance at Mt. Equinox with other famous hill climb records is in order. The four climbs which have been prominent in this country at different times are: Pikes Peak, Mt. Washington, Grand Junction, and now Mt. Equinox. A summary of these climbs is given in Table 19-4.
It will be seen that the average achieved on Mt. Equinox is the highest yet attained in a prominent American speed hill climb. It is also interesting to note that the speed is comparable to those obtained in very short speed hill climbs held in Great Britain. The present record for the 0.75-mile Shelsley Walsh, which has only one moderate S-turn and a couple of gentle bends, is approximately 53.0 mph, while at Craigantlet, Raymond Mays's record average is 49.2 mph. While none of these records are strictly comparable, the figures show that the FWD put up an outstanding show by any standards.
Bill Milliken on his FWD Miller winning the first Mt. Equinox Hill Climb in record time, 1950. Far left, Dave Whitcomb. Our time was 6 min., 59.4 sec. (54.2 mph average).