Bilstein Gas Pressure Shock Absorbers ThyssenKrupp .

Bilstein Gas Pressure Shock AbsorbersThyssenKrupp Bilstein of America

Oval Track Motorsports ShocksModelApplicationDescriptionPageAK SeriesPure stock, Enduro,Street Stock (stock mount),Mini-Stock36mm/46mm diameter sealedsteel body stock mountshocks and struts8-9SG SeriesStock Cars, IMCA/UMPModifieds, Midgets,Mini-Sprints, Modified Litesand Dwarf Cars36mm diameter sealedsteel body, convertsto coilover applications10SZ SeriesSL SeriesSLS SeriesModifieds,Late Models andStock Cars/Hobby Stocks46mm diameter sealed steelbody, converts to coiloverapplications, off the shelfvalvings11 - 13SN SeriesSNS SeriesModifieds, Late Modelsand Sprint Cars46mm diameter steel body,aluminum billet cap withschrader valve, linear ordigressive piston, rebuildable14ASB SeriesSprint Cars, Midgets,Mini-Sprints, TQ Midgets,Micro-Midgets andFormula CarsUltra lightweight 36mm aluminum 15body, sealed non-coilover designor rebuildable threaded bodymodels availableASN SeriesModifieds, Late Modelsand Sprint Cars46mm diameter threadedaluminum body with schradervalve and circlip rod guide, linearor digressive piston, rebuildable,optional adjustable shaft16BGT SeriesLate Models, Super LateModels, Sprint Cars,Dirt Late Models andBig Block Modifieds46mm diameter threadedaluminum body with 60mmnitrogen compartment, 14mmpiston shaft, rebuildable17Big TrackSeriesRebuildable shocksfor NASCAR classesB46-60BG8 – 46mm aluminumbody with 60mm gas chamber,linear, digressive or RBT piston,screw in rod guide18B46-GN3 – 46mm aluminumbody, linear, digressive or RBTpiston, screw in rod guide,optional adjustable shaft

Table of ContentsPage 4 . . . . . . . . . . .Monotube vs. Twin-Tube ShocksPage 5 . . . . . . . . . . .Why Race On Bilstein Shock Absorbers, Q & APage 6 . . . . . . . . . . .Bilstein Pistons and ValvesPage 7 . . . . . . . . . . .Tools and AccessoriesPage 8-9 . . . . . . . . .AK Series, Mounting Types and Specs / AK PackagesPage 10 . . . . . . . . . .SG SeriesPage 11 . . . . . . . . . .SZ SeriesPage 12 . . . . . . . . . .SL SeriesPage 13 . . . . . . . . . .SLS Series NEWPage 14 . . . . . . . . . .SN & SNS SeriesPage 15 . . . . . . . . . .ASB SeriesPage 16 . . . . . . . . . .ASN SeriesPage 17 . . . . . . . . . .BGT SeriesPage 18 . . . . . . . . . .Big Track SeriesPage 19 . . . . . . . . . .Adjustable Shafts and Compression CanisterPage 20 . . . . . . . . . .Dwarf Car Set-UpsPage 21 . . . . . . . . . .Micro Midget and Modified Midget Set-UpsPage 22 . . . . . . . . . .Midget and Mini Sprint Set-UpsPage 23 . . . . . . . . . .Sprint Car Set-UpsPage 24 . . . . . . . . . .Stock Car / Hobby Stock Set-UpsPage 25 . . . . . . . . . .I.M.C.A. Type Modified Dirt Set-UpsPage 26 . . . . . . . . . .Dirt Modified Set-UpsPage 27 . . . . . . . . . .Super Dirt Late Model Set-UpsPage 28 . . . . . . . . . .I.M.C.A. Type Modified Asphalt Set-UpsPage 29 . . . . . . . . . .Asphalt Modified Set-UpsPage 30 . . . . . . . . . .Late Model Stock / Super Late Model Asphalt Set-UpsPage 31 . . . . . . . . . .How To Shock Tune Your Chassis, Trouble Shooting The Car At The TrackFor Complete Information Contact:Aftermarket & Motorsports – EastAftermarket & Motorsports – WestMooresville, NCPoway, CAPhone: 1-877-666-7662Phone: 1-800-537-1085bilsteinUS.com3

Monotube vs. Twin-TubeThere are two basic types of shock absorber used in today’s short track racing: the conventionaltwin-tube reservoir shock and the monotube gas pressure shock pioneered by Bilstein.NITROGEN GAS AREA – Puts shockoil under pressure to totally preventcavitation (foaming) and shock fade.DIVIDING PISTON WITH O-RING –Separates gas and oil and is moveableto accommodate rod movement intothe tube. Bilstein shocks are notgas/oil emulsion shocks.MONOTUBE SHOCK BODY – Insidewall has finished tolerances of anengine cylinder. Outer surface iscadmium or nickel plated fordurability. Single tube designdissipates heat more effectively thantwin-tube.AIR SPACE – When the shock ismounted upside down (to reduceunsprung weight), air space residesover base valves making eventualshock fade a certainty.BASE VALVES – Allow oil to exit theinner tube when displaced by theshaft on the compression stroke andto re-enter on rebound stroke.GAS BAG – A plastic bag, containinggas under very low pressure, is saidto “absorb” cavitation. This design isalmost totally ineffective in preventingshock fade.UPPER PRESSURE CHAMBERWORKING PISTON – Consists ofpatented deflective disc valve stack forprecise performance. Bilstein discsare spring steel which outperformstainless steel and produce longer life.Piston uses powder metal technology.OIL CHAMBER – Special oil ispressurized by the gas area onto thedividing piston to preventcavitation (foaming) for consistent,fade-free performance.PISTON ROD – Case-hardened andhighly polished steel strong enough tolift 20 tons.ROD GUIDE and SEALS – Highpressure Viton inner rod guide sealsensure a perfect fit for consistent,fade-free damping and long lifeperformance.Most short track racers still run on the older style, twin-tubeshocks. But if you watch closely, you’ll find more of yourcompetitors switching to the up-to-date, monotube gaspressure shock absorbers. Although there are other brands ofmonotube gas shocks making an appearance in America’s pitareas, Bilstein technology is so far ahead and so different, thattheir performance cannot be equaled.Bilstein’s larger piston area produces instantaneous response tothe slightest suspension movements. Dead spots in a Bilsteinare an impossibility.Deflective disc valving in Bilstein shocks eliminate the need forcheck valves and tiny coil springs that cause inconsistencies inshock valving. All Bilstein shocks of the same part numberproduce, with little variation, the same damping forces. In other4INSIDE TUBE – Damping forces aregenerated in the smalldiameter tube.PISTON and VALVING – The smalldiameter piston develops dampingforces with check valves operated bylittle coil springs.LOWER PRESSURE CHAMBEROUTER TUBE – This is a reservoir tostore oil displaced by the shaft on thecompression stroke.OIL RESERVOIR – By storing oil inthe outside tube, heat dissipation isslowed more than the monotubeshock design, even if the outer tube isaluminum.words, when you bolt on a Bilstein, you know what shockvalving is on your car.Shock absorber performance fades away when the oil in theshock cavitates (foams). Conventional twin-tube shocks, thatare called “gas charged,” contain a small plastic bag holding aminuscule amount of gas under a small amount of pressure.This design, while low in cost to manufacture, is ineffective onthe track.Under extreme G-forces, on rough tracks and in high heatconditions, “gas charged” twin-tube shocks do not resistcavitation as effectively as monotube gas pressure shockabsorbers. This is the reason that all NASCAR, Indy Car,Formula One and Off-Road racers long ago discarded twin-tubeshocks in favor of monotube gas pressure technology!

Why Race On Bilstein Shock Absorbers?1. Because the valvings are consistent, yourset-ups will be more precise.3. Bilstein shocks don’t fade. Your chassis will handleas good at the end of the race as it did at the start.2. Bilstein’s larger piston and deflective discvalving develop control force when youneed it, at the slightest movementof the suspension. You’ll getweight transfer when youneed it, better controlunder braking and yourtires will stay on the trackthrough the rough spots.4. Bilstein shocks are rugged. They last for years andare rebuildable and revalvable.5. When the advantages of Bilstein gaspressure shocks are tallied up, you willhave spent less money on shock absorbersand collected more money at the paywindow.Bilstein’s unique deflective disc valving system allows forexact valving of both compression and rebound movements.ANSWERING THE RACERS’ QUESTIONSThe following are some commonly asked questions andtheir corresponding answers concerning Bilsteinmonotube gas pressure shock absorbers:Q. Why is the shaft on a Bilstein shock always extended?A. As monotube gas shocks, Bilstein shocks are under gaspressure to deliver the most responsive valving forultimate control. This pressure, called the gas reactiveforce, and Bilstein’s perfect internal seals force the shaftto be extended.Q. Is the car more difficult to scale with Bilstein shocks?A. Bilstein shocks have no effect on the results as youweigh the four corners. The gas reactive force inBilstein shocks may raise your car’s ride heightslightly. Simply adjust the chassis downward to thedesired ride height.Q. Does Bilstein offer specific applications for thevarious dirt and asphalt racing series?A. As the set-up charts in this catalog indicate, Bilsteinhas shocks specifically valved for both dirt and asphaltsurfaces of various track lengths.Q. Are Bilstein shocks difficult to understand and use?A. After reviewing the various set-ups in this catalog,you’ll be ready to select the proper shocks for yourspecific race car. Bilstein valving is precise. Onceyou purchase your Bilstein shocks, you can be certainthey will perform at peak efficiency throughouttheir long life.Q. I can buy twin-tube shocks for less money thanBilstein shocks. Why should I spend the extra money?A. As we point out in this catalog, Bilstein shocks arefabricated from the highest quality components for longlife performance. Typically, Bilstein shocks are onlyslightly more expensive than twin-tube brands. Sincethey will far outlast conventional shocks, Bilstein shockscost much less over the long run. Bilstein shocks are theleast expensive way to lower your lap times.Q. The companies that sell only twin-tube (low pressuregas) shocks say their design outperforms monotube(high pressure gas) shocks. How can I know the truth?A. Take a trip to a local discount department store thatsells replacement shocks for cars and trucks that driveon the street. You’ll find shocks priced from about 8.99 to 29.99. All of the shocks on display will betwin-tube shocks. Their price reflects the fact that twintube technology is relatively unsophisticated and verylow cost to produce. At a new car dealership you’ll findthat low cost base line cars and trucks are factoryequipped with twin-tube shocks that add very little tothe cost of the vehicle. Factory installed Bilstein shockscan also be found on Mercedes-Benz, Ferrari, Porsche,Toyota TRD, Roush and many other high performancevehicles around the world. Finally, take a stroll throughthe pit area at a NASCAR Cup, Busch, Craftsman Truck,CART, IRL or Formula One race and you’ll find not atwin-tube shock in sight! The top racing engineers inthe world always use monotube gas shocks! By searchingout the facts, you will know the truth.and the truth willmake you faster!5