The Two-Five Challengers

Road & Track - January 1972

The melodramatic finish of the 2.5 Challenge Series, rife as it was w/body contact, desperation driving, surprise winners, lightning raids by technical inspectors & 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 3 best examples of the leading makes perform, & why; how they're built, & why, & how they finished during the season. (The reason they finished as they did is so involved w/the last race & 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 w/a track test of the winning Mustang, the class of the big car class, so to speak, & thus the car to write about. For '71 there was a new small car class w/a unique set of rules, resulting in 3 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 & group procedure & dissect all 3 examples. Especially since the 3 top teams were willing to cooperate. They, too, were curious as to how their cars performed against the clocks & tape measures, & they enjoyed seeing how their rivals measured up as well. Fine people, incidentally, & 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 & displacement. Engine modifications are very nearly unlimited, while everybody gets to use front spoilers & flared fenders & all cars are limited to a rim width of 7".

The minimum weight varies w/engine & type. A car w/DOHC must weigh 1.2 lb. per cc. A SOHC engine w/crossflow manifolding carries 1.15 lb/cc, SOHC w/o crossflow gets 1.1, pushrod crossflow have 1.05 & 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 w/the Alfa Romeo camp, altho in practice the Wetson Racing team is a median; well financed but w/less than full factory support.

The team sponsor is Herb Wetson, owner of a restaurant chain. Wetson likes racing & 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 3 cars, for drivers Horst Kwech (also serving as team manager), Bert Everett & Harry Theodoracopulos, & a full complement of mechanics. The constructor of title is Kwech's company AUSCA, Inc., in Libertyville (IL).

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 & 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 & 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 & does very well. That's real racing, & 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 (& Datsun), the team BMWs are constructed by a firm owned by the team manager, in this case E.F. Engineering, Culver City (CA), & Stu Haggard. Gregory is a good driver, team leader Don Pike is a very good driver. Haggard is a skilled & practiced builder/manager & Sarah Gregory is a lady, one of the few women in racing who manage to be charming & 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 & company surely needs no introduction. BRE is the Datsun factory team, winning championships while designing & producing performance & competition parts, for the team & retail sale. Datsun takes part in competition in Japan & is venturing into European rallying w/the 24OZ, but the U.S. is Datsun's major export market & 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 & most experienced crew & the most money. The factory share is well into 6 figures. And worth it. BRE performs at an incredible level of craftsmanship & showmanship. Drivers John Morton & 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 & teams from doing likewise.

Construction

The Racing Alfa begins w/2 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, & the weight distribution is 48% front, 52% rear, to reduce the understeer.

All body panels are steel & 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 3 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 & few tracks today are really rough. Tuning for a given circuit or for driver preference is done by swapping anti-roll bars altho in extreme cases the springs are changed as well.

The brakes are ventilated discs, front & rear, replacing the production solid discs. The OE servo remains. Wheels are magnesium Minitites, the 15" diameter of the production car wheels being retained for the bigger footprint.

The engine figuratively designs & assembles itself. The Alfa DOHC is a classic, been around for years while engineers & racers practiced w/it. The Wetson engines are simply straight forward racing engines, i.e. carefully radical camshafts, giant Webers, ports & combustion chambers reworked, all the internals lovingly matched & balanced. As the rules predicted, the Alfa engine is the most powerful in the series, & produces the most power per cc.

General note: The Alfa tested uses a 1750cc 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 & smaller engines mean less weight & faster cornering. Each builder thus has to decide whether more power & top speed is more or less important than lighter weight & faster cornering. Neither AUSCA nor BRE are sure they're right.

Gregory Racing had the choice more or less forced on them. All 3 team cars use the 2000cc engine & they don't have the power they need even then.

The SOHC engine meant adding weight. There's a 99 lb skid plate under the fuel tank at the rear & 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 & 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 w/a full tank, & 52/48 empty, the slight forward weight bias being best for the handling conditions sought. Haggard uses relatively soft springs, & tunes the chassis via camber angles. Unreal. There are shims & bushings to vary the rear wheel angles, & the tower for the front struts is slotted laterally. The mounting bolts can be loosened & the strut moved back & forth tipping the wheel in or out. The entire suspension is thus variable.

The BMW engine has been a problem. When mods were permitted, Gregory bought engines from a race engine builder in the homeland. They were illegal under U.S. rules, & didn't produce adequate hp even then. (The team members quip that DIN stands for "Deutschland Invented Number.") Since then, the team has built its own engines. At 1st, there was power & no reliability. They went back to the beginning & have been working w/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 w/a non-boost system is worth the extra physical exertion.

The Datsun strips down from production weight. The hood, front fenders, trunk lid & fender flares are fiberglass, & the rear & side windows are Plexiglas. But the surprise is that the roll cage is much simpler (& 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 & 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 w/a selection of anti-roll bars. Moving the struts & 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 & money can do. The factory supplies all the parts Brock can use & the BRE shop is jammed w/test gear. Brock's engine men have done a superlative job. Normal changes along the lines of monster Solexes & such, but the changes have improved both power & 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 & cured the weak points.

Testing

Everybody wins something. The Alfa comes out ahead in the power & acceleration department. Even w/the weight per cc limit, the Alfa DOHC delivers the most hp per weight of the 3 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, btw, so we'd be sure each car was giving its best ... the Alfa w/R&T observer aboard & 5th wheel behind out-dragged the Datsun w/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 & 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 & hold it until the car stopped dead. The Alfa did nearly as well, but the reading varied & 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 w/out fade & the distance was only a few feet shorter than the Alfa's.

The Datsun had the best cornering power & handling. This is perforce a subjective judgment. The testing was done after the RIR race & before the season closed at Laguna Seca. One day was all we could ask the teams to donate, & the skidpad section of the normal test would have required another day. But from watching the cars race, from checking qualifying times & 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 RIR. 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, & it's strong at a lower rpm than the others, as well. Push down & buzz off. The steering is heavy at low speeds, due to the drag of the racing tires but lightens w/velocity. Driving the Alfa at relatively high speeds, tho, 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 & to apply some--not all--of that power. But not too much, because that will break the heavy end loose, & 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 & the other Wetson drivers do so well is a tribute to their skill. The BMW is much easier to drive, & the lower power hasn't that much to do w/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 & the softest ride & what seems to be the highest degree of body roll under equal cornering speeds. The attitude thru 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 & the correct line w/power, & full power could be fed to the wheels on exit w/out 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 & 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 w/out drama. A piece of cake.

The Datsun has temperament. No low end power at all, a double-disc clutch that catches & stalls the car unless lifted w/exactly the right motion & timing, an exhaust note that tells the world of smaller pistons going up & down at a great rate. The Datsun is stiffly sprung & its characteristics follow the weight location just as happens on the other cars. Neutral, but ready to leap either direction. This provides Morton w/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 & Pike motors thru in the BMW, Morton hurls the Datsun from lock to lock w/visible changes in attitude. It nips around smartly & feels as if it would as soon nip around on the straight as well, especially over bumps & 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 1st you should know how the series & 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 '71 series began, the BRE Datsuns weren't completed. The Alfas, led by the Wetson team, took an early lead w/the Gregory BMWs close behind them & ahead of the various completely private Alfas. Alfa won 2 straight, Datsun arrived & won 2 straight, Alfa won again, Datsun won 2 straight again. Alfa finished 1st & 2nd at Watkins Glen when Morton ran out of gas, Morton won Riverside going away, & the Seattle finale was canceled. Cries of anguish, because if Datsun could win that last race, & when both makes counted their best 8 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 & Nels Miller & 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 & Kwech drove like, well, like 2 top drivers trying to win a national title for team & factory. Kwech had the edge on the straighter sections, Morton caught & passed him on the twisty bits. They swapped back & 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 6" 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 & 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 & 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 w/tech inspectors pulled onto the track & threw its books over the winning Alfa. They removed the Alfa's fuel tank & measured it. Too big. Much too big. The metal framework was oversize & the foam-filled bladder was free to expand & hold more than the 15 gal. permitted by the rules. The stewards put 16 gal. in then, emptied the bladder & filled it again the next morning. With 17 gal. Kwech was DQ'd. Morton was the winner. Datsun got 9 points & 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 DQ'd. 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 w/it. The only less obvious fraud would be the installation of a Chevy V8.

Against this, how could an intelligent team-& 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 6 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 1st words for a choice of 2 final paragraphs:

Despite the weight handicap imposed by an extra 2 gallons of fuel, the Alfa Romeo won ...