The last Group B Audi in North American Rally | Fr...

Intimidation Issue

What Frank Sprongl loves most about his Group B Audi is its means to intimidate. “First there may be the popularity for dominance within the rally world,” says Sprongl. “It appears like an aggressive machine which means critical busi­ness. And it seems like one thing fierce is coming down the street­the 5 cylinders give it a particular, refined tone. There is no mjstak­ing it is an Audi.”

However it’s the flames blasting out of the exhaust pipe that places each­one on notice-and it occurs at any time when Sprongl shifts or deceler­ates. Going from full throttle to partial throttle restricts the quantity of air going into the combustion chamber, leading to an extra of gas. The unburned gas is pumped into the recent exhaust manifold, the place it ignites and blows out via the turbo and tailpipe like a fire-breath­ing dragon. “The flames are cool,” says Sprongl, “particularly when racing at evening. The flash lights up the woods.”

Sprongl provides th.a! you simply cannot beat the reliability of the automobile. “It is constructed like a military tank. The structural rigidity and mechanical com­ponents are very good. It is laborious to interrupt this automobile.”

The Dream Automotive

Now 33 years previous, Sprongl began rallying at 18. The next yr, he bought a chance to see a Group B Audi A2 up shut, and his life was by no means the identical. With his brother Dan, he purchased an Audi Coupe Quattro road automobile and transformed it for ral­mendacity at their efficiency store, 4 Star Motorsports, positioned in Georgetown, Ontario, one of many largest rally retailers in North America.

The automobile gained many cham­pionships from 1990 via 1992 earlier than they determined to improve to the last word rally machine: a full Group B Audi. The S2 shell was pre­pared at 4 Star Motorsports, the engine was a Lehmann unique, and the drivetrain, transmission and suspension have been Audi Sport. The automobile debuted on the finish of 1993 and immediately dominated the rally scene.

“The distinction between the Coupe Quattro and the A2 Lehmann engine was evening and day,”say Sprongl. “There was a mind-boggling distinction in acceleration and high pace. It accelerated sooner than I might shift. The primary time I drove the automobile. my knees have been shaking and I could not get out of the seat. It was such an adrenaline rush. Now I am used to the sheer acceleration and braking means; I might use extra horsepower.”

Tremendous Lehmann Engine

“This engine was 115 p.c developed,” says Sprongl, including that it has a lot energy and torque it digs trenches off the beginning line and slams his head again towards the seat. “The ten-valve is a phenomenal engine: all of the bugs have been labored out. It requires minimal service:· Upkeep consists of altering the oil after every rally, checking the plugs and rotor cap each three rallies, altering the turbo twice a yr, and checking the timing belt annually.

Lehmann not solely designed and constructed the A2 engine, however he nonetheless performs all main repairs for the workforce. “We by no means have to fret concerning the engine,” says Sprongl. “We ship it to Liechtenstein when there’s an issue, and once we get it again, we merely bolt it in and hook it up. We solely need to examine the oil. water and turbo stress. The engine arrived sealed; we do not know precisely what he did, however we’re certain it would run completely.” Earlier than Lehmann sends an engine to a buyer, he checks it on the dyno.

Lehmann’s six-person store is understood for ex­appearing element work, from mapping the ECU com­puter, to working with particular factories throughout Europe to customized fabricate elements comparable to pistons. connecting rods, cam shafts and crank shafts. “It is costly, however I am certain these pans are the most effective on the planet,” mentioned Heinz Lehmann, including that not a single engine half is identical as within the manufacturing road automobile model.

Uncommon Engine Components

A number of the elements for this uncommon competitors engine have develop into very tough to get, such because the aluminum engine block.”I at all times inform the Sprongls that in the event that they crash the engine, we will have a giant downside,” says Lehmann.

In response to Lehmann, there have been a mini­mum of 200 A2 engines constructed to qualify for race homologation, and to this point his store has rebuilt about 160 of them. Museums and personal collectors personal most of those; solely a fe11 are actually entered in competitions.

The engine administration system is fundamental. controlling airflow, ·temperature and timing. It’s preset at Lehmann’s store and dyno examined with the engine. The rev limiter can also be preset at 8200 rpm and isn’t adjustable.

The engine is cooled by the big quantity of oil within the dry sump lubrication system with an unlimited oil cooler within the rear spoiler, and by a high-efficiency inventory radiator. The air for the engine is cooled by a turbo intercooler that’s 5 occasions bigger than the inventory unit. The engine exhaust system options mandrel-bent, three-inch pipe for prime circulate.

The Energy Benefit

The sheer energy of the engine is an actual benefit in rally, based on Sprongl. “In the event you enter a nook too scorching, you may downshift and get away with going via at full throttle; in a decrease horsepower automobile, you’d slide off the street. Or, if you happen to’re unsure what a nook does and take a low-risk method by braking, you need to use the ability of the automobile to blast out of the nook and make up the time you misplaced.”

Sprongl says the automobile by no means strains on steep pitches, and he would not need to shift down. “It has no barrier in acceleration; if you happen to hit the rev limiter and have room on the street, you may go up one other gear.” 1-1-o_wever, he added that if you happen to’re not cautious, accelerating within the improper spot can put you into the weeds.

‘Torque is definitely extra essential than horsepower in rallying,” says Sprongl, “particularly at low rpm. I haven’t got to be in the precise gear out of a nook; the torque pulls me out and helps acceleration. The automobile by no means bogs down in sand, mud or snow.”

The Audi Sport competitors gearbox is an important ingredient within the energy equation. It has a brief gear ratio with a high pace of 120 mph. The shut gear ratios means Sprongl loses only a few rpm throughout shifting. With the hydraulic-activated clutch triggered by a button on the shifter, he elimi­nates the foot motion delay and saves beneficial time with each gear change. “It shifts as quick as I can pull the shifter,” he explains. The light-weight, cross-drilled flywheel permits the engine to rev up extra rapidly; it con­nects to a single-plate competitors clutch.

Designed for Abuse

The automobile’s suspension is constructed for battle, based on Sprongl. “I can go over something at any pace; I do not again off over the tough stuff. We ignore the cautions within the route ebook to a sure extent. We’ve got no prob­lem hitting jumps flat out. It permits us to make up time on opponents the place they need to again off.”

The bulletproof suspension is product of metal, together with strut, spring and shock housings, though a separate light-weight aluminum sus­pension is used for hillclimbs. Further-strength tubular management arms maintain the struts in place. Spherical rod ends are used all through to elimi­nate flex within the elements; there are solely 14 rubber bushings and mounts within the automobile. “With the stable mounts you are feeling the engine vibrations, however the sooner you go, the smoother the journey,” says Sprongl.

Not a lot of the suspension is adjustable on the Quattro. The spring charge is modified just for winter rallies to be extra forgiving. Totally-threaded struts allow elevating or reducing the automobile by a number of inches for street condi­tions. Adjustable sliders on the management arms enable camber changes. Sprongl selects spring charges and shock valving from the Audi Spon prod­uct line.

Free Dealing with

Sprongl likes the automobile to deal with free, and units the toe, camber and journey top accordingly. “I need to be certain that if I come over a crest and the street unexpectedly modifications path, I can simply rotate the again finish of the automobile round.”

He defined that when he first bought the automobile, the rear wing pushed down the again and picked up the entrance finish when accelerating, which made the automobile understeer. He added the entrance spoiler for front-end down power that neutralizes the automobile’s dealing with.

The automobile encompasses a competitors energy steering pump straight pushed off the camshaft, an Audi Sport steering rack, and a smaller steering wheel to quicken steering. A collapsible steering column was added for security.

The brake system consists of twin grasp cylinders, four-pot alumi­num alloy calipers and 280mm vented discs. The brake bias is alter­ready entrance to again solely on the brake pedal meeting, not contained in the automobile like many rally automobiles. “I need to focus on driving and avoiding errors, not taking part in with the brake bias.” says Sprongl. Energy and traction are transmitted via Yokohama tires.

Inflexible Bodv Design

The shell was designed for little physique flex, with a triangulated roll cage welded to the physique at 30 to 40 factors. The roll cage ties to the entrance and rear suspension, rear di fferen­tial mounts, and the entrance and rear strut tow­ers. “A stiff automobile handles higher, with extra con­trol, stability and stability,” Sprongl explains.

To resist the street abuse, steel rein­forcement was added to crucial mounting factors for the suspension and engine; the trans­mission tunnel was doubled, and customized brackets have been made to bolt the engine, trans­mission and rear differential on to the chassis, versus sitting on a subframe.

To guard towards the rock bathe below the automobile, Kevlar shielding covers the rear dif­ferential, a part of the rear drive shafts, and the outer CY boots and joints. Excessive-density plas­tic protects the half shafts, decrease management arms and flooring; a steel plate professional­tects the rear brake discs and calipers; a 10mm Kevlar skid plate protects the engine and transmis­sion.

The shell is totally seam welded and lightened wherever potential. Com­posite panels are used for the hood, rear hatch, entrance fenders and entrance bumper. Home windows are Lexan apart from the windshield.

Dependable Programs

Fast-release half shafts present simple repairs between rally phases; the half shafts, in addition to the prop shafts and axles, are all Audi Cornp.

The gas system consists of a 22-gallon tank plus two gas filters, pumps and pickups. “It is a gasoline pig,” says Sprongl, including that gas financial system is all relative to turbo increase. He usually will get about 5 miles per gallon throughout a race, and 15 to 18 mpg transiting on the freeway.

{The electrical} system features a inventory battery, competitors alternator, and a single belt working the alternator. Simple-access plane circuit breakers and relays have been put in to keep away from altering fuses on evening phases. A detachable pod with six auxiliary lights illumi­nates the tree-lined programs at evening,

The sprint has been simplified with crucial gauges solely: tachometer, increase, oil tempera­ture, water temperature, oil stress, amp/volts and gas gauge. Racing seats and security gear spherical out the inside.

Upgrading Efficiency

To enhance his growing old Quattro, Sprongl would love a six-speed sequential competitors gearbox for faster shifting with an adjustable middle differential. “Some high automobiles have viscous couplings in an energetic middle differential which permits use of the hand brake in hairpin corners,” explains Sprongl. “The Audi has no middle differential. If I locked the rear wheels, the engine would stall due to the direct output.”

Different upgrades on Sprongl’s want checklist embody an anti-lag system to eradicate turbo lag and lack of increase stress when shifting, present suspension know-how with two- to a few­method adjustable dampening, traction management, extra environment friendly brakes, and an up to date shell.

“After all, the last word could be an Audi 20-valve motor with 750 horsepower, full anti-lag and the six-speed sequential gearbox with energetic differentials, however that will re­quire a number of hundred thousand {dollars},” explains Sprongl. “The motor alone is over $ I 00,000.” However in all motorsports, sponsorship cash dictates upgrades. Group sponsors in 2000 included Yokohama, Bosch, Peltor Intercoms and Loctite.

“I really like the status, the reliability, the uncooked energy and the ruggedness of the Quattro,” says Sprongl, “however to some extent, really feel like I am working a automobile out of the Flintstone period. Nothing can compete in acceleration and straight-aways, however I lose time within the bumps and tight, twisty sections. Suspension and dealing with know-how has advanced dramatically, and fast dealing with is the important thing to success on fast-changing rally roads. In addition, the brand new rally motors are designed differently-the setup between horsepower and torque is completely different. with excessive torque at decrease rpm to drag you out of the corners.”

For the reason that Group B Quattro is changing into extra outdated tech­nology-wise, the workforce has de­cided that 2000 would be the final yr of full competitors for the well-known fire-breathing automobile. It’s the closing chapter within the Group B period. “Nothing will evaluate to the Audi Quattro, it would simply be completely different,” says Sprongl. He plans to make use of it for particular occasions and for the Mt. Washington Hillclimb. “The brute energy is ideal for that race,” the course record-holder mentioned with a smile.