Driving the Ex-Birkin Blower-4½ Single-Seater Bentley

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Some History and Road Impressions of Russ-Turner’s Famous Brooklands Lap Record Car

“The Bentley was in grand inns, roaring very high round the Byfleet banking, dropping to the Fork in a puff of dust, clipping the verge of the Vickers’ sheds and going on to the Members’ banking each time with that characteristic and disturbing little snake that those who saw the car in action are not likely to forget. From the notorious bump it leapt some 70 feet clear of the Track, into the Railway Straight” — from a description of Birkin’s first lap-record bid in 1930, as described in Chapter XX, page 219 of “The History of Brooklands Motor Course” by W. Boddy (Grenville, 1950).

The Blower-4½ single-seater Bentley with which the late Sir Henry Birkin, Bt. twice broke the Brooklands outer-circuit lap record, was very much in evidence at the time when I was a regular visitor to the Track. Its appearance raised anticipation to high levels, because it was one of the fastest cars racing, effectively taking the place of the legendary aero-engined monsters of an earlier decade. To see the slight figure of the Baronet taking this long, slim, blue (later red) Bentley round the bankings was indeed exciting, his polka-dot scarf streaming out behind his helmet and the big car snaking viciously over the bumps.

From which it can be seen that I was an avid admirer of this combination of man and machine. I used to watch it in most of its races but on one occasion, when the offer of a holiday with friends in the New Forest in a 9/15 Renault fabric saloon proved a counter-attraction, I can still recall how on the Bank Holiday Monday my thoughts were far away and how earnestly I tried without success to obtain an evening paper, to discover whether or not Birkin had again broken the lap-record.

This individual Bentley began as one of the supercharged 4½-litre sports-racing four-seaters which Birkin favoured when he was building the racing team sponsored by the Hon. Dorothy Paget, although W.O. Bentley preferred to stake his faith in the Speed Six. It was later given a two-seater fabric body for the 1929 BRDC 500-Mile Race but retired when the fabric caught alight. It was during the winter of 1929/30 that it was rebuilt as a track car in the form with which we are here concerned. The 10 ft. 10 in. wheelbase chassis had its front brakes removed. It was chassis No. HB 3402 and the engine, which was the very first blower-4½ litre power unit, was No. SM 3901. The car was prepared in the workshops of Henry Birkin and Cooper Ltd. at Welwyn Garden City and a single-seater body was designed for it by Reid Railton and built by A. P. Compton & Co. of Merton. Originally a cowl was fitted to the scuttle to deflect air over the driver’s head but Birkin apparently couldn’t see over it and it was soon replaced by an aero-screen

What could be described as a Thomas-type cowl was fitted over the special, small Aston-Martin-like radiator and front dumb-irons, the hand brake lever and gear lever were outside the cockpit, a headrest was used, and the front axle faired over. The engine was a normal ,Villiers-supercharged overhead-camshaft, sixteen-valve 100 x 140 mm. (4,398 c.c.) one, but the crankshaft was counter-balanced and special very substantial, H-section con.-rods were designed for it by Amherst Villiers. Output was increased to 240 b.h.p. An axle ratio of 2.58 to 1 was installed, and 32 x 6.50 Dunlop tyres were used. This special single-seater Bentley was ready for the opening Brooklands Meeting of 1930. It was entered by Miss Paget and Birkin found himself on scratch in his very first race with the car. The supercharger casing was leaking and had been only partially repaired with Plasticine and there was some clutch slip but nevertheless Birkin finished second, behind Staniland’s Bugatti, the Bentley having lapped at fractionally better than 100 m.p.h. on its standing lap and then at 123.89 m.p.h. That was in the Kent Short Handicap. Unplaced from scratch in the Surrey Short Handicap, Birkin reserved his best run for the Kent Long Handicap. As ever on scratch, he increased his s.s. lap to over 101 m.p.h., put in a flying lap at 126.73 m.p.h. and won at 119.13 m.p.h. from a Bugatti and Dunfee’s Ballot. This earned a re-handicap of “owes 3 sec.” in the Surrey Long Handicap, and Birkin, who was to become very bitter about the Brooklands handicapping, simply withdrew soon after starting.

However, such an excellent performance on its very first appearance promised great things of the Bentley for the Easter races. It was now entered as Bentley I. Inevitably on the scratch mark, and giving the Leyland Thomas an 11 sec. start, there was a stir when Capt. Birkin (as he then was) brought the car out for the very first race, the Bedford Short Handicap, and an even greater wave of enthusiasm when he ran home first, at 117.81 m.p.h., leaving the second man 150 yards behind. The car was really going now. The s.s. lap was completed at over 107 m.p.h., the flying lap at 134.24 m.p.h. As I have said, the Birkin single-seater Bentley was as great an attraction for the Brooklands crowd as the 350 h.p. V12 Sunbeam had been in the early nineteen-twenties and the Napier-Railton was to become some years later. But, in fact, it was not the fastest of the Track cars when it first appeared, this honour belonging to Kaye Don and one of the supercharged 4-litre V12 Sunbeams. At the Easter Meeting of 1930, Birkin hoped to change that. First, he was to race in the Dorset Lightning Short Handicap and was to have started four seconds after Cobb’s old 10½-litre V12 Delage. But once again handicappers Dutton and Ebblewhite put Birkin back to “owes 7 sec.”. He pulled in soon after being flagged away, the journalists proclaiming that the plugs were playing up but I think it more likely that Birkin was thinking of his future handicap and his car. He had every reason to do so, because in an hour and 25 minutes, after a Bentley Handicap had been run off (remember?—Hamilton won the Woolf Barnato Cup) and Birkin had driven Bentley II in a Mountain race, the single-seater was to run in a 3-lap Match Race against Jack Dunfee’s GP Sunbeam. The Sunbeam was in trouble, which gave Birkin a clear track on which to attempt to raise the lap-record. It stood to Don’s credit, at 132.46 m.p.h. But not for much longer! For the Bentley did its first round, from a Pond start, at 133.88 m.p.h. and followed this with three laps, respectively at 134.60, 134.60 and 135.33 m.p.h. The blower singleseater from Welwyn was Brooklands fastest car!

It should have run in the very next event, the Bedford Long Handicap. But the scratch start was changed to one of “owes 20 sec.” and although this time Birkin elected to race, and twice equalled his new lap-record (no fluke there!) the best he could do was to run in fourth, a length behind Dunfee’s aged Ballot. In a busy day, Birkin had one more race but was again heavily re-handicapped and he slowed after ¾-of-a-lap, convenient for driving into the Paddock up the Finishing straight!

The situation now became dramatic. The Bentley had been right off-form at the BARC Club Meeting (or else was trying to repair its handicap) and Birkin was absent at Whitsun. It was then that Kaye Don retook the lap-record, the Sunbeam clocking 137.58 m.p.h., having equalled Birkin’s speed in an earlier race. So interest as to what Birkin would do about this rose to fever pitch. At Easter he had flown to Brooklands, broken the record, then flown back to Le Touquet to have the promised celebration dinner with millionaire Woolf Bamato. At the age of 17 I just lapped it up, and Birkin and the Bentley were my unquestionable heroes!

Thus many eyes were on Birkin and the blue Bentley when it took up scratch position in the Cornwall Senior Short Handicap at the August Bank Holiday Meeting.

Birkin was content to lap at 127.38 m.p.h. and finished third behind Daybell’s 30/98 Vauxhall and Pole’s 17-litre Mercedes, although his opening lap had been a quick one, at over 106 m.p.h. He scratched from the next race and, no doubt as a protest against the handicap, substituted Craig’s 2.3 GP Bugatti, in which he would have won had he not forgotten that it was a slower car, not allowed the same freedom at the Fork as the Bentley, and been disqualified for crossing the wrong safety-line. However, the 25-mile Gold Star Handicap was to give the Bentley its chance. On scratch, giving the next car to him, Purdy’s GP Sunbeam, 58 sec. start, Birkin was expected to regain the lap-record. Unfortunately he found the wind too strong and after going round at 131.76. m.p.h. he pulled in after five laps with the fuel tank leaking. Nor did he start in his next two races, while I do not suppose the “Old Crocks” race which closed the day’s sport appealed to him . . . .

Absent from the Autumn races, the single-seater was run in the BRDC 500-Mile Race. George Duller was appointed as co-driver to Birkin but in practice they experienced a front tyre burst and a wild skid and Duller never seemed to like the blower-4½, which he couldn’t tame by talking to it, as he did a horse. In the race the Bentley proved it was no marathon runner, making a series of pit stops, and finishing 9th and last. Dorothy Paget withdrew her support for Birkin’s team cars that winter but retained the single-seater.

Those who remembered the car in its better days were delighted that it made a re-appearance at the 1931 Whitsun Meeting. Birkin had now come into the title, being nominated by his entrant, Miss Paget, as Capt. Sir Henry Birkin, Bt. Alas, the car was unplaced, its best lap 131.41 m.p.h. In the Gold Star race it was only lapping at around 127 m.p.h., the wind making it, a tricky car at the best of times, difficult to control. Clearly, something had to be done. What Birkin did was to call in G. E. T. Eyston, who recommended one of his Powerplus vane-type superchargers, to replace the former Amherst Villiers Roots-type. This was duly fitted, retaining the 2 in. SU carburetters, and to obviate icing hot water from the radiator was fed to the supercharger casing. On the Saturday before the August Bank Holiday, when Birkin was to make a special attempt on Don’s lap record, it was Capt. Eyston who was seen in the Bentley, trying things out. However, the speed didn’t want to go above about 134 m.p.h. and in the attempt Birkin did five laps, but never bettered 134.97 m.p.h. He did this on two consecutive circuits, so was presumably flat out. He was entered for only one race—handicap contests never appealed to him—and in this, the London Lightning Long Handicap, in which for once he wasn’t on scratch, for Cobb’s Delage gave the Bentley five seconds, Birkin managed a fine opening lap at over 108 and then lapped at 136.45 m.p.h., to finish third.

At the Autumn BARC Meeting Birkin found the position reversed, Cobb leaving four seconds before him, in the Cumberland Senior Long Handicap, his only race in the Bentley, although he won the Mountain Championship in a Maserati and drove a 2.3 Alfa Romeo. The Bentley gave him third place, behind Widengren’s OM and the big Delage. The “500” was again a fiasco, Dr. Benjafield driving the car but the Bentley retiring with a stretched valve stem.

In his book, “Full Throttle”, Birkin said he had managed unofficially to equal Don’s lap-record a few days prior to the previous season’s 500-Mile Race but in trying to better it the next day the Bentley caught fire as it was coming off the Belfast banking and Sir Henry had to stand on the seat and steer as well as he could in a crouching position before coming to rest. What Benjafield thought about such high-speed work before a long race isn’t recorded! This, it seems, decided Birkin to revert to the original Villiers blower.

Birkin was disinclined to give up, the Bentley representing his link with the old Bentley days, and for 1932 the single-seater was repainted red and the cylinders were bored out 0.5 mm., raising the swept volume to 4,442 c.c. Later in the season, an extra oil pump was fitted to the nose of the supercharger, scavenging the sump and delivering the lubricant to the oil tank at the rear of the chassis, as the engine had been converted to dry-sump. Incidentally, as Birkin was so keen on “wearing the green” I wonder why the car was painted in the Italian colours?

Before the lubrication system was altered to convert the engine to dry-sump, the Roots-type Villiers had been further modified. The electron centre casing was replaced with an aluminium centre casing and this together with oversize rotors increased the maximum boost to 12 lb./sq. in. The side-draught SUs were replaced by two enormous horizontal down-draught ones. These 62 mm. carburetters passed a gallon of fuel every 59 sec., whereas previously the flow at full throttle had been a gallon every 73 sec. This gave a consumption of approx. 2 m.p.g. at racing speeds, on a 40/30/30 methanol-benzole-petrol mixture. In conjunction with the new lubrication system a small pack-type oil-cooler was located in the oil-line close to the n/s rear front spring hanger. The downdraught carburetters were used for the successful 1932 lap-record run, and the drysump lubrication was ready for that year’s BE Trophy Race.

The Bentley was going very well indeed by 1932. In practice four days before the Easter Brooklands Meeting Birkin achieved his goal, breaking Don’s record by 0.2 sec., setting the lap-record to 137.96 m.p.h. This lent interest to the subsequent race appearances. Birkin was second in the Norfolk Lightning Short Handicap (in which the Bentley and Cobb’s Delage had started together from scratch) lapping at 134.24 m.p.h. Although slower in the “Long” race, he won from his old rival, the Delage, at 122.08 m.p.h. in spite of a nasty down-banking skid. In his first race Birkin had apparently caught his foot on the spare oil tank, which spoilt his getaway, for normally the s.s. lap was done at nearly 108 m.p.h.

In the BRDC British Empire Trophy Race, run in a series of heats and a final over the outer-circuit, a splendid coming together of the fastest track cars (which surprisingly is ignored in “A Racing History of the Bentley”, although Dunfee’s Speed Six also took part in it), Birkin got to within second place behind Eyston’s 8-litre Panhard Levassor in his heat when a front tyre went to pieces. The pit-stop was a long one but the Bentley eventually finished 4th, at 116.95 m.p.h. Birkin made a bid for victory in the Final but after passing the Panhard and averaging over 124 m.p.h. for 50 miles he came in for water and later retired with a cracked block, ominous white smoke streaming from the exhaust pipe. However, he was OM again at the Whitsun meeting, with a standard-dimension cylinder block meeting Cobb’s Delage again in the Nottingham Senior Short Handicap. The problem was now passing the Delage, which had to go high on the banking to get by the fast small cars. The Bentley finished two feet behind it, in 4th place, after lapping 8½ m.p.h. faster than Cobb once it got into its stride. The task in the Gold Star race was hopeless and Birkin came in.

At the 1932 Guy’s Gala Meeting the Bentley won the Long Handicap under gusty conditions at 124.33 m.p.h. but a tyre tread came off the o/s rear tyre during the Duke of York’s race, striking Birkin on the shoulder, but not before he had equalled his lap-record. At the BARC August Meeting Cobb and Birkin raced together in a 100 sovs. Match Race over three laps. The Bentley accelerated more slowly than its older but much bigger-engined rival and was 3.8 sec. behind after the first lap. It cut this down to 1.4 sec. next time round and at the Fork on the last lap was within 1/5 of a sec. of the Delage. Birkin recalls that “As we came off the Members banking I felt the Bentley, as it were, hang above it (the Dalage) for an instant and then shoot ahead”. He won the duel by 4/5 of a sec., and did that last lap in a strong wind at 137.58 m.p.h. During this hectic race the streamlined head-rest came off the body and flew high in the air. Later that afternoon he was second in the Hereford Lightning Long Handicap 3/5 of a. sec. behind Shuttleworth’s Bugatti, lapping at 136.45 m.p.h., from scratch, of course.

That was the last appearance of this very fast and successful Brooklands car. Birkin was estimated to have done more than 50 laps of Brooklands in it at 135 m.p.h. or more (I can count 11 official BARC race laps at this speed and 30 at over 130 m.p.h.) and had twice broken the lap-record with it, which he equalled on several occasions, when this was becoming a very difficult task. Sir Henry died in 1933 and surprisingly the Bentley was never raced again before the war, and Miss Paget either wouldn’t, or couldn’t, sell it. Sir Henry had said it was an extremely difficult car to drive fast so perhaps there were no takers.

In 1939, however, the late Peter Robertson-Roger blew up the engine of his ex-Birkin Pau 4½-litre at Donington and sought out the blower single-seater as a source of spares. He charmed the car’s titled owner into parting with the car, which was towed away behind John Morley’s Packard and a lorry-load of spares. A two-seater, long-tailed body, made by Chalmers of Redhill, was put on the chassis by Peter and John after the war and when Peter died in 1958 his will left the famous Bentley to John. “Rusty” Russ-Turner bought it and after using it for a while in this form, to his ever-lasting credit he refitted the track radiator, later put the single-seater body back on, and had the original radiator cowl repaired by Caffyns. He had to alter the cockpit somewhat, to accommodate his large frame, but the car looks very decently original and is on its original UU 5871 registration, which Morley had traced to a milk-float in Ireland! It is raced in VSCC, BDC, and other events and used on the road in its old Brooklands guise.

No-one could have been more fitted to acquire and restore the famous single-seater than B. M. Russ-Turner. As a youth I went to Brooklands by train and Austin 7 and he by bicycle and four-push-rod Salmson. We both worshipped the car and its intrepid driver and Rusty in later life owned many special Bentleys. He has spent a vast amount of time and money on restoring the blower-4½ track car and it was a great honour when he invited me to drive it, especially as he had spent the whole of the preceding week replacing yet another cracked block especially for the occasion.

When we arrived at his Sussex cottage in the BMW, there on the lawn was the car I had come down to drive and discuss and the other 4½-litre which now has the two-seater body which was on the single-seater when Rusty bought it and which he hopes soon to Supercharge. As the engine of the blower car needs much warming-up and this had been done, I lost little time in going out in it, paced, or more correctly shown the way, by Russ-Turner’s open Bentley Corniche. Originally Birkin climbed in by placing a foot on a piece of fairing over the brake gear but a step has since been provided. The cockpit would originally have fitted me as it did Tim but now I needed a thin cushion behind my back. The four-spoke steering wheel is very big, so there were some gymnastics to get both legs beneath it. Seated, the long muchlouvred bonnet stretches purposefully ahead and you are confronted by a magnificent array of dials and controls. The big Jaeger rev.-counter has pride of place, reading in steps of 500 r.p.m., from 500 to 6,000. To its right are the water and oil temperature gauges, with a pull-out knob below them which frees the reverse stop on the gear-lever should one need to travel backwards. To the left of the rev.-counter one finds the oil-pressure gauge, reading to 100 lb./sq. in., and the supercharger gauge giving a minus or suction reading on one side of the dial and the pressure scale, 0.3, 6, 9, 12 on the opposite side. Lower down or under this crowded dashboard, which by the way is the original and took a week to rub down, are a horn-push, Ki-gass, a hand throttle, and the glass-bowl oil drip-feed for the rear supercharger bearing. What looks like a direction-indicator control is used to test the dual magnetos. Outboard of this is the air pump for fuel feed, no longer used, as electric pumps were original equipment, and above this there is an ammeter, as a starter is now fitted. The smaller gauges are Smiths.

Having assimilated all this, and found the starter button I was shown the little switch for an electric fan which I was to use if the water temperature got. to 90° C (it has a warning light) and told that of the two brass levers on the steering-wheel boss, one is inoperative and the other is the advance-and-retard which, once pushed up, could be ignored.

The body, although a single-seater, is off-set, so there is quite a lot of space on one’s left. Here there is the electrical panel, with ignition switches, a boxed Smiths speedometer with mileometer, a hand-grip, and spare goggles hanging-up, etc. Behind the red bucket seat the bulkhead is in the original blue paint, with a Brooklands admission label and a carefully preserved Scrutineer’s ticket mounted on it. Even now I have not exhausted the list, because the cockpit floor presents a battery master switch, a brake-adjuster knob, a long plug spanner, and a Firemaster Fury fire-extinguisher. Rusty has made few concessions to road motoring, apart from the obvious items among those mentioned above and the front brake axle, and the brakes are still cable operated. Somewhat over-awed, I pressed out the clutch, which has very little movement and feels solid, pressed the starter button, eased in 1st gear with the outside gear-lever and prepared to go motoring! Being conscious that I was privileged to be driving a one-off, very valuable and quite irreplaceable car, and not wishing to write off both the Bentley and the Corniche in one big shunt, I drove very sedately.

There was no need for this, however, apart from caution, because the brakes work exceptionally well, the equal of today’s hydraulic brakes, so that one is never conscious that there is nearly two tons of motor car to control from speeds which are deceptively fast, and it steers easily and rides very comfortably. That is one aspect of the single-seater. Do not imagine that it is in any way dull! Depress the central accelerator and things happen. The acceleration is exceptionally good, the response far better than that from most big-engined vintage sports cars, even in top gear, in which I satisfied myself that 3,200 r.p.m. comes up very easily indeed, without need to wait for special conditions or occasions, the Bentley running straight as an arrow.

The long polished brake-lever, outboard of the stubby gear-lever, is easy to reach and just about as effective as using the pedal. To lock its ratchet you pull it back and with the other hand reach down and depress a small catch. The gear-change, once it is realised that only a touch of throttle is needed when double-declutching from top into 3rd, the clutch-stop very effective, is quite easy to accomplish, while the upward change from 2nd into 3rd is one of the most satisfying I have experienced—I found I would snatch my way into second at the approach of a traffic roundabout simply for the sheer pleasure of going back into third! The lever then moves just as nicely into top, but the movement is deceptively short.

Looking ahead over the exciting bonnet, I was not really aware of the length of tail behind me; but in traffic it is reassuring to know that it does not overhang the chassis and that a n/s rear-view mirror gives a reasonable view behind. The typical tangy note from the Brooklands exhaust system on the n/s, the other fascinating noises as the needle of the blower gauge swept towards “12”, and the great waves of heat which soon engulfed me, the cockpit Side against which the silencer nestles like an oven, added to the excitement of this memorable drive. No wonder passers by look with clearly-expressed interest at one’s swift passage! Traffic was heavy on the hot August day but the Bentley intended for Brooklands proved entirely manageable. The steering does not kick, so that a hand can be nonchalantly lifted to drop or raise one’s goggles and there is truly nothing much to do other than change gear and get on with it. I had been instructed either to open or shut the throttle and not to trail it as part throttle soots the plugs. So, on these congested roads it was mostly a case of bursts of exhilarating acceleration, accompanied by the roar of the engine and crackle of the exhaust, or slowing under the influence of the brakes with their big, deeply ribbed drums. . . . Towards the end of the run, when a traffic jam brought me to rest, the heat did rise towards 90° and I duly switched-in the fan. Otherwise, no drama. But it was very satisfying and I am indebted to the Bentley’s owner for the experience. I have now tried two of the Brooklands lap-record cars, as the Hon. Patrick Lindsay allowed me to briefly sample the Napier-Railton at Silverstone. . . .

After we had gone to lunch in the Corniche, we chatted about the history and the resuscitation of this historic racing car. It is an enormous tribute to Russ-Turner how much of it is still original. The one-piece body was found in a field and re-painted, deliberately leaving its battle scars on the panels. Incidentally, it bears the original maker’s plate. As I have said, Caffyns saved the original radiator cowl, but the bonnet was beyond repair. The No. 1 engine is still in the car, with the prototype Villiers blower and the original twin 2-in. SUs. Even the aero-screen Birkin looked through is there, although Rusty says sadly that he does not know how much longer the strip of oak on which it is mounted will stay put.

The Bentley is now on 7.00 x. 17 Dunlops and although Russ-Turner has the original very heavy nose-piece of the 2.56-to-1 axle, he now uses a Speed Six axle with a 3.0-to-1 ratio. This gives 30 m.p.h. per 1,000 r.p.m. in top gear. At Brooklands Birkin could rely on a theoretical 139.12 m.p.h. at 4,000 r.p.m. (off the bankings he probably saw 4,200 = 145 m.p.h.). When he races the car Rusty keeps to a maximum of 3,500 r.p.m. and tries not to spin it in the wet (it once came within inches of damaging itself on the Maggots sleepers at Silverstone in an uncontrollable gyration due to a burst o/s rear tyre). To be competitive it would need to be geared 26 m.p.h. per 1,000 but, even so, it can clock around 82 sec. for the Silverstone Club circuit.

Reverting to originality, the radiator is the Welwyn one, but it took a year to retube So is the 45-gallon fuel tank in the tail, but the oil tank behind it had to be fabricated. Incidentally, it was there before the engine was converted to dry-Sump; both tanks have impressive quick-action fillers. The oil tank holds 7 gallons but is filled with 3½ gallons of Castrol GP50. An under-scuttle oil tank used to replenish the sump and feed the blower drip-feeds, of which there were two, for the front and the back bearing, until, on the advice of Amherst Villiers, the front bearing was lubricated by a greaser to cut down oil loss. A new exhaust system had to be made up but the original was there as a pattern, and I need hardly add that every switch is correctly positioned as far as photographs have been able to provide data. The location of the ignition switches, etc., on the n/s cockpit wall looks like a mod. but that is where it was in Birkin’s day. Similarly, the instruments are the originals. Russ-Turner lowered the bonnet line to suit the original radiator cowl and Caffyns did what had to be done to the body and re-wired the car, so that it now has a lighting set, etc. However, the mudguards are quickly detachable; as Rusty demonstrated so that we could photograph the Bentley stripped for action.

Birkin had a special gearbox, with centres different from a standard D-type box and with the very noisy wide-toothed “mangle” gears, said to have been fitted because Birkin liked to push the lever quickly about without much in the way of double-declutching! This was obviously of more use on his road-racing Cars. Today a normal D-type gearbox is used. Some of these chamfered-tooth gear wheels are among Rusty’s exhibits. He also has the pair of 62-mm. d/d SUs and Birkin’s very thin red seat cushion, filled with a bare minimum of strip foam rubber. No wonder he complained of the roughness of Brooklands! Pictures suggest that he must have been about a foot out of the seat in the cramped cockpit at times. . . . This in spite of triple Hartfords and twin B & D shock-absorbers at the rear and triple Hartfords on the front axle—still all fitted.

Some idea of the present capabilities of the Bentley can be gained by Russ-Turner’s speeds over the BDC flying kilometre at Ghent, namely 119.2 m.p.h. in 1968 and 123 m.p.h. in 1970. He runs the car on VIP 100-octane from his own garage, getting about 10 m.p.g. on the road, and five m.p.g. in races.

One of the problems has been cracked cylinder blocks. This was not unknown at Brooklands, where with the 12 lb. boost and a 6.0-to-1 c.r. Birkin was placing a lot of stress on blocks with a thickness of only 5 mm. when properly cored. Russ-Turner thinks a 5½-to-1 cr. is about the maximum with petrol but even so has suffered—and new blocks, only an extra millimetre in thickness, cost some £1,000 to cast, and there is no guarantee!

Having had my drive in the car and looked around it, we fell to chatting about its history. Birkin employed quite a large staff to build the blower-4½ team cars at Welwyn. Clive Gallop was Works Manager, Bertie Browning the Foreman. Bill Rockall was the engine and blower man. Fitters and mechanics included the walker Bert Whitlock, Jock Finlayson, John Logan, E. A. Jennings, Edwards, Lawrence and Jackie, etc. Amherst Villiers designed the Roots-type blower and the counter-balanced crankshaft and heavy H-section con.-rods for the racing engines, of which only three such cranks were built. Very early on it is thought that an oil-cooler was used on the single-seater with the wet-sump engine, placed behind a simple dumb-iron fairing. The Powerplus supercharger used for a while was much lower than the Villiers, which seems to have given rise to the suggestion that the big d/d carburetters were used with it. This appears to be erroneous. They were subsequently part of the reinstated Villiers set up. This put their intakes high up inside the radiator cowl and eventually an air scoop to them was fitted on the n/s of the cowl, but right at the end of the Bentley’s career and it was never raced with it.

The dry-sump was probably devised to counter oil surge on the Brooklands bankings, when it was realised that higher speeds were about to be attempted. The car was often reported to have retired with “lubrication trouble” and this probably implied that it had run all its bearings. To get a better feed and cooler oil the dry-sump system was needed, and to obviate re-designing the engine with an extra scavenge pump this pump was put on the nose of the blower, in spite of the long run of piping involved between it and the oil tank behind the fuel reservoir. None of the experts who have described the car seems to have realised that it eventually had dry-sump lubrication and it was only when Louis Giron was building up one engine out of the wrecked No. 4 and No. 1 power units for Robertson Roger that the special sump cast for the No. 1 engine, with its off-takes for the piping, made this apparent. It weighs 50 lb. or some 14 lb. more than a normal blower-4½ sump. Why a tail oil tank was fitted in the wet-sump days is not clear to me.

The magnificent rebuild was finally completed on April 29th, 1971, and John Morley was invited to the champagne celebrations. No doubt at this party the amusing story was recalled of how, when the new owner was seeking to get the original Reg. No. for the car, the suspicions of Surrey CC were aroused. They were told the expert to contact was— Rusty Russ-Turner, none other! The chassis number is on the o/s front dumb-iron, whereas W.O. had them stamped on the ns dumb-irons. Which is no doubt why the Log Book quoted the Eng. No. as the chassis No. By the way, Tony Fabian had worked on the Bentley when he was at Caffyns and today he is employed by Russ-Turner and is still working on the car.

Incidentally, my drive on the road in this single-seater was really quite appropriate, because Gallop used to drive it thus from Welwyn to Brooklands, pausing, if a plug oiled-up after going through London, on the hill by Putney Cemetery, near the KLG factory. With rear-wheel brakes only, he must have concentrated pretty hard. . .

W.B.