THE MELODRAMATIC FINISH of the 2.5 Challenge series, rife as it was with body contact, desperation driving, surprise winners, lightning raids by technical inspectors and a new set of equally surprised winners, does more than delight the emotionally uninvolved.
The finish also lends itself perfectly to our purposes; describing how the three best examples of the leading makes perform, and why; how they're built, and why, and how they finished during the season. (The reason they finished as they did is so involved with the last race and its stunning conclusion that we aren't going to tell you why. Just the facts, to be given at the proper time.)
This 3-car trick comparison test was in the planning, stages, actually, before the season ended. Last year we observed the Trans-Am series' end with a track test of the winning Mustang, the class of the big car class, so to speak, and thus the car to write about. For 1971 there was a new small car class with a unique set of rules, resulting in three makes of sedan, similar in concept yet unique in detail, contending for the title. Ergo, the way to top last year's test was to combine track and group procedure and dissect all three examples. Especially since the three top teams were willing to cooperate. They, too, were curious as to how their cars performed against the clocks and tape measures, and they enjoyed seeing how their rivals measured up as well. Fine people, incidentally, and we, herewith tender our thanks.
The Rules
The 2.5 CHALLENGE series may be the best thing SCCA ever did. The prime factor is the rules, best described as a handicap. The cars must use an engine of homologated type and displacement. Engine modifications are very nearly unlimited, while everybody gets to use front spoilers and flared fenders and all cars are limited to a rim width of 7 in.
The minimum weight varies with engine and type. A car with double overhead camshafts must weigh 1.2 lb. per cc. A sohc engine with crossflow manifolding carries 1.15 lb/cc, sohc with one-side manifolds gets 1.1, pushrod crossbows have 1.05 and plain pushrod engines are one for one. The SCCA reasoned (correctly) that given equal freedom to tune, the dohc engines will have more power than sohc engines, which will outpower pushrod engines, etc. The goal, therefore, was to limit all makes by equalizing power to weight. There remains the freedom of Superior design: If Maker A provides a superior pushrod engine, that make will defeat Maker B, whose unit is a so-so- dohc. And the best car won't always be the most expensive car.
The Teams
THE LEADING teams are themselves a study in SCCA professional racing. Using alphabetical order as the only fair way to arrange the list, we begin with the Alfa Romeo camp, although in practice the Wetson Racing team is a median; well financed but with less than full factory. support.
The team sponsor is Herb Wetson, owner of a restaurant chain. Wetson likes racing and while the cars bear his name, there's no hint of commercialism, no invitations to buy hamburgers, nor even any mention that Wetson has hamburgers to sell. There are three cars, for drivers Horst Kwech (also serving as team manager), Bert Everett and Harry Theodoracopulos, and a full complement of mechanics. The constructor of title is Kwech's company AUSCA, Inc., in Libertyville, Ill.
The parent factory provides mostly good wishes. Alfa Romeo is deeply involved in competition, so deeply that Alfa has its own racing subsidiary, Auto Delta, builder of the factory's cars for the world manufacturer's title. The in-house big league operation means that little money gets out of the plant. Alfa has a modest support program for club racers and AUSCA gets some cash, more parts, all the technical advice there is, shop space while on tour, but it's not a factory-backed team.
The BMW effort lacks even the factories good wishes. Gregory Racing is in entirely private effort: owners Gerry and Sarah Gregory didn't plan it that but that's how it's been so far.
The factory doesn't know. The U.S. representatives of BMW don't want to know. The team approached BMW here, but was told the manufacturer already, races in Europe and does very well. That's real racing, and U.S. racing, isn't, runs the official view, so the U.S. fans must be content to know that in the homeland, BMW wins. The officials have never, evidently, watched the BMW owners' clubs attending 2.5 races en masse. And keeping their upper lips still.
Like Alfa (and Datsun) the team BMWs are constructed by a firm owned by the team manager, in this case E.F. Engineering, Culver City, Calif., and Stu Haggard. Gregory is a good driver, team leader Don Pike is a very good driver. Haggard is a skilled and practiced builder/manager and Sarah Gregory is a lady, one of the few women in racing who manage to be charming and knowledgeable at the same time. But Gregory Racing doesn't have the money or facilities that the other teams have, so BMW hasn't done as well as its rivals.
Pete Brock, for instance, BRE team and company surely needs no introduction. BRE is the Datsun factory team, winning championships while designing and producing performance and competition parts, for the team and retail sale. Datsun takes part in competition in Japan and is venturing into European rallying with the 24OZ, but the U.S. is Datsun's major export market and the 2.5 series is Datsun's major racing effort. As a bonus, Yutaka Katayama, president of Datsun U.S., is a racing enthusiast. He was a fan before Datsun went racing. Going to the races to watch his make win is Katayama's idea of a perfect day. BRE has the biggest shop, the most equipment, the largest and most experienced crew and the most money. The factory share is well into six figures. And worth it. BRE performs at an incredible level of craftsmanship and showmanship. Drivers John Morton and Mike Downs both won national SCCA titles while working their way up. Those tempted to boot about money conquering all are reminded that there's nothing to prevent other factories and teams from doing likewise.
Construction
The Racing Alfa begins with two handicaps. One is inherent; considered as a racing car, the GTV develops extreme understeer. The other is imposed; the dohc engine forces the Alfa to carry more weight per cc than its rivals. Kwech has used the latter to compensate for the former.
The Alfa must be built up, that is, weight must be added to the car after it's equipped for racing. The Alfa carries its ballast in the back, and the weight distribution is 48% front, 52% rear, to reduce the understeer.
All body panels are steel and the roll cage is a complicated space frame, serving to stiffen the unit body as well as protect the driver. The rules allow suspension modification in detail but not type. The Alfa alone of the three makes described here has a live rear axle but it doesn't seem to be a problem. Kwech has the patterns of travel well under control and few tracks today are really rough. Tuning for a given circuit or for driver preference is done by swapping anti-roll bars although in extreme cases the springs are changed as well.
The brakes are ventilated discs, front and rear, replacing the production solid discs. The stock servo remains. Wheels are magnesium Minitites, the 15-in. diameter of the production car wheels being retained for the bigger footprint.
The engine figuratively designs and assembles itself. The Alfa dohc is a classic, been around for years while engineers and racers practiced with it. The Wetson engines are simply straightforward racing engines, i.e. carefully radical camshafts, giant Webers, ports and combustion chambers reworked, all the internals lovingly matched and balanced. As the rules predicted, the Alfa engine is the most powerful in the series, and produces the most power per cc.
General note: The Alfa tested uses a 1750-cc engine. The other cars on the team are 1600s. The BRE Datsun tested is a 1600. The other BRE car is an 1800. For all cars, larger engines mean more power and smaller engines mean less weight and faster cornering. Each builder thus has to decide whether more power and top speed is more or less important than lighter weight and faster cornering. Neither AUSCA nor BRE are sure they're right.
Gregory Racing had the choice more or less forced on them. All three team cars use the 2000-cc engine and they don't have the power they need even then.
The sohc engine meant adding weight. There's a 99-lb skid plate tinder the fuel tank at the rear and a 50-lb skid plate under the engine in front. More ballast goes at the right center of the car, to equal the driver's weight and balance the car longitudinally. There are brackets for still more ballast beneath the driver's seat, to provide for adjustments for the various scales used at various tracks.
The BMW roll cage is as elaborate as the Alfa's, again to stiffen the unit body.
The BMW is balanced 51% front, 49% rear with a full tank, and 52/48 empty, the slight forward weight bias being best for the handling conditions sought. Haggard uses relatively soft springs, and tunes the chassis via camber angles. Unreal. There are shims and bushings to vary the rear wheel angles, and the tower for the front struts is slotted laterally. The Mounting bolts can be loosened and the strut moved back and forth. tipping the wheel in or out. The entire suspension is thus variable.
The BMW engine has been a problem. When modifications were permitted, Gregory bought engines from a race engine builder in the homeland. They were illegal under U.S. rules, and didn't produce adequate power even then. (The team members quip that DIN stands for "Deutschland Invented Number.") Since then, the team has built its own engines. At first, there was power and no reliability. They went back to the beginning and have been working with the internals, to make the engine last. This year the team's engines have lasted, but they simply don't have competitive power.
Brakes are normal Trans-Am: big disc, in this case the bigger discs from the BMW 2800. The power assist is removed, Haggard's view being that the extra control possible with a non-boost system is worth the extra physical exertion.
The Datsun strips down from production weight. The hood, front fenders, trunk lid and fender flares are fiberglass, and the rear and back windows are Plexiglas. But the surprise is that the roll cage is much simpler (and lighter) than the cages in the rival cars. The Datsun cage is not designed to stiffen the body. Even with weight removed, the body is stiff enough for racing. The Japanese are not famous for, uh, over-engineering or for suspension work. Katayama says that Japanese motoring is slow, which is why the production cars are sometimes lacking in handling when compared to German and Italian products, but he adds that Japanese roads are rough. The designers therefore give much consideration to chassis stiffness. Take that, myth of flimsy Japanese products.
The Datsun is neatly balanced 50/50. The 510's strut towers are slotted like the BMW’s, but Brock says routine suspension tuning is done with a selection of anti-roll bars. Moving the struts and varying the camber is done only when a course is rough enough to make front bump steer a problem.
The engine is a display of what time and money. can do. The factory supplies all the parts Brock can use and the BRE shop is jammed with test gear. Brock's engine men have done a superlative job. Normal changes along the lines of monster Solexes and such, but the changes have improved both power and strength. So the Datsun develops more power than expected because it's wound tighter than the others. It can be wound tighter because the development has revealed and cured the weak points.
Testing
Everybody wins something. The Alfa comes out ahead in the power and acceleration department. Even with the weight per cc limit, the Alfa dohc delivers the most power per weight of the three cars. It will out-accelerate them handily. The curves are close, surprisingly so, but during the testing-the team drivers did the driving for the figures, by the way, so we'd be sure each car was giving its best-the Alfa with R&T observer aboard and fifth wheel behind out-dragged the Datsun with Morton running solo.
The BMW wins the braking. Kwech told us it would, said that all year he's watched the more powerful cars pull away out of turns and been able to catch up again because the BMW would out-brake them. The BMW could pull one "g" as soon as Kwech's foot hit the pedal and hold it until the car stopped dead. The Alfa did nearly as well, but the reading varied and the distance from 80-0 was longer for the lighter Alfa. The Datsun wouldn't pull as high a "g" reading, there was some fade during a test that several passenger cars can pass without fade and the distance was only a few feet shorter than the Alfa's.
The Datsun had the best cornering power and handling. This is perforce a subjective judgment. The testing was done after the Riverside race and before the season closed at Laguna Seca. One day was all we could ask the teams to donate, and the skidpad section of the normal test would have required another day. But from watching the cars race, from checking qualifying times and from knowing that the Datsun is as quick as the others while not having the acceleration or braking, we know the Datsun has an edge around turns.
Driving
Besides, we drove them around Riverside. We will not wax too lyrical over the joys of driving such machines, as you would
turn green if you knew that actually driving these cars was even more fun than you imagine it was.The Alfa was a challenge as well. The engine is enormously strong, as the figures show, and it's strong at a lower rpm than the others, as well. Push down and buzz off. The steering is heavy at low speeds, due to the drag of the racing tires but lightens with velocity.Driving the Alfa at relatively high speeds, though, is like juggling a hammer. At the entrance to a corner, the front end plows, the weight shift not having cured the car's normal understeer. The corrective technique is to use a lot of positive steering lock and to apply some--not all—of that power. But not too much, because that will break the heavy end loose, and when the tail starts to come, it comes fast. When you are correcting one imbalance, then, you know that the techniques you use are those that will lead to another imbalance. Tricky business. That Kwech and the other Wetson drivers do so well is a tribute to their skill.The BMW is much easier to drive, and the lower power hasn't that much to do with it. Limiting power to insure reliability has kept the power in the middle of the rpm range, so the engine needn't be catered to. The brakes are noticeably heavier than those on the other cars, but again, once convinced that they will work astonishing well, the new driver can use them effectively.
The Gregory cars have the lowest spring rates and the softest ride and what seems to be the highest degree of body roll under equal cornering speeds.The attitude through curves is one of very mild understeer, enough to call for normal steering lock on entrance, but no more than that. The BMW could be held in a neutral attitude and the correct line with power, and full power could be fed to the wheels on exit without fear of wheelspin. Some of this is due to the relative lack of power to spin the wheels, true, but it's also due to the soft suspension. And to the irs. The turn 7 exit has a patch of pavement broken and patched to the consistency of cobblestones. The Alfa hopped on its live rear axle, the Datsun skittered on its stiffly sprung irs, but the BMW just glided over the section without drama. A piece of cake.
The Datsun has temperament. No low end power at all, a double-disc clutch that catches and stalls the car unless lifted with exactly the right motion and timing, an exhaust note that tells the world of smaller pistons going up and down at a great rate. The Datsun is stiffly sprung and its characteristics follow the weight location just as happens on the other cars. Neutral, but ready to leap either direction. This provides Morton with instant response, which must be good, but there's an equal demand for a driver who can use the response. At speed, the Datsun looks the most spectacular. While Kwech fights his Alfa and Pike motors through in the BMW, Morton hurls the Datsun from lock to lock with visible changes in attitude. It nips around smartly and feels as if it would as soon nip around on the straight as well, especially over bumps and ridges. If this sounds difficult, it may be a false impression. Possibly the Datsun only works when driven hard.
The Season
All this testing, etc., will be tied together shortly, but first you should know how the series and the group test got into the problem you'll learn about just before the conclusion. Care to read that again? Not too clear, but neither is the conclusion.
Anyway. When the 1971 series began, the BRE Datsuns weren't completed. The Alfas, led by the Wetson team, took an early lead with the Gregory BMWs close behind them and ahead of the various completely private Alfas. Alfa won two straight, Datsun arrived and won two straight, Alfa won again, Datsun won two straight again. Alfa finished first and second at Watkins Glen when Morton ran out of gas, Morton won Riverside going away, and the Seattle finale was canceled. Cries of anguish, because if Datsun could win that last race, and when both makes counted their best eight races, the score would be tied. The SCCA felt obligated to provide as many races as scheduled. So it was arranged to have the last race at Laguna Seca, on the Saturday prior to the Can-Am.
The 2.5 closer must have been the best Saturday racing ever. Morton/Datsun had the pole, followed by Kwech/ Alfa, Downs/Datsun, Lee Midgely/Alfa and Nels Miller and Pike, both in BMWs.
Laguna Seca turned out to be the equalizer the SCCA had in mind when the rules were drawn up. And we couldn't have chosen a better site to illustrate the findings of the test. Morton and Kwech drove like, well, like two top drivers trying to win a national title for team and factory. Kwech had the edge on the straighter sections, Morton caught and passed him on the twisty bits. They swapped back and forth, they rubbed fenders, when Morton slid sideways Kwech pushed him into a full circle. Not on purpose, it was just that the cars were six inches apart when Morton lost it. A beautiful race.The flaw: There were expectations that the cars would need fuel. But lo, Morton came in for gas and Kwech kept right on going. He built up the lead of the day, a full 10 seconds. As he crossed the finish line victorious, the Alfa engine sputtered and died.
Brock by this time had rushed up to John Timanus, the SCCA technical director. I protest, said Brock. Don't bother, said Timanus, the stewards of the meeting are ahead of you.
Kwech's car had barely stopped rolling when a wrecker festooned with tech inspectors pulled onto the track and threw its books over the winning Alfa.They removed the Alfa's fuel tank and measured it. Too big. Much too big. The metal framework was oversize and the foam-filled bladder was free to expand and hold more than the 15 gal. permitted by the rules. The stewards put 16 gal. in then, emptied the bladder and filled it again the next morning. With 17 gal. Kwech was disqualified. Morton was the winner. Datsun got nine points and won the series.
Conclusion
Oh, *##%**+!!, as they say in the funny papers. In the normal group test, the drivers rate all the cars on the aspects that matter in road cars, performance, brakes, comfort, styling, etc. This would make no sense in a track test, because what matters in racing is winning. So it was decided after the test but before the final race that the group test winner would be whichever make won the title.And now look. The official winner was beaten. The unofficial winner was disqualified. Either way, the result is dissatisfying.
Kwech said after the race that he bought the fuel cell in good faith. One can't even draw a conclusion there. On the one hand, an outsize fuel tank is so easy to detect that it's hard to imagine a competent team trying to get away with it. The only less obvious fraud would be the installation of a Chevy V-8.
Against this, how could an intelligent team-and the Wetson team is certainly intelligent-not discover extra fuel capacity? These cars are filled via hand-held 3-gal. cans. How often could they put six such cans into the tank before wondering about it?
We will therefore take advantage of a literary device. Pick your own ending, bestowing the awards as you wish. Here are the first words for a choice of two final paragraphs:
Despite the weight handicap imposed by an extra two gallons of fuel, the Alfa Romeo won....
Once the evil plans of its rival were exposed, Datsun won....
If your choice is determined by your personal preference, well, so be it. If it wasn't for emotional involvement, none of this would have happened anyway.