Page 621 - 2017 Racecar Engineering Circle Track Parts and Accessories Catalog

GUN DRILLED THE KERA CONCEPT AND PROPER AXLE SELECTION
SHORT TRACK AXLES Although the left and right axles are different lengths, they are typically the
Oval track axles are manufactured from ultra same diameter, and inherently lies the problem. Due to the fact that the right
high strength alloy steel for outstanding yield and axle is longer, it has a lower spring rate than the left. The result is that left axle
tensile strength. CNC-hobbed splines provide does not “wrap-up” as great as the right and the car has a tendency to steer
precise tolerances and even torque transfer, while right on initial acceleration since the left rear sees the power first.
heat treating, shot peening and REM finishing By simply using a smaller diameter left rear axle with the KERA (“Kleban
increase durability. Axles are gun-drilled .578" to reduce rotating weight. Equal Response Axles”) split diameter concept (also referred to as wrap axle),
torque steer reaction can be equalized under both acceleration and decelera-
Part No. Description Length O.D.
SOTAGY11152850 31-Spline Axle 28.5" 1.115" tion. By referring to the accompanying chart, you can determine the proper axle
SOTAGY11302850 31-Spline Axle 28.5" 1.130" diameter for the right and left side.
SOTAGY11153000 31-Spline Axle 30.0" 1.115" RECOMMENDED AXLE SET-UPS
SOTAGY11303000 31-Spline Axle 30.0" 1.130" Left Right
SOTAGY11453000 31-Spline Axle 30.0" 1.145" Application Axle Dia. Axle Dia.
SOTAGY11153050 31-Spline Axle 30.5" 1.100" IMCA/USMTS Style A-Mods
SOTAGY11003050 31-Spline Axle 30.5" 1.115" (650+ HP) With Gun-Drilled Axles
SOTAGY11303050 31-Spline Axle 30.5" 1.130" Standard KERA 1.130" 1.145"
SOTAGY11453050 31-Spline Axle 30.5" 1.145" Optional “Tuner” 1.115" -
SOTAGY11003150 31-Spline Axle 31.5" 1.100" Optional Heavy Right Side* – 1.165"
SOTAGY11303200 31-Spline Axle 32.0" 1.130" IMCA/USMTS Style B-Mods & Sport-Mods
SOTAGY11453200 31-Spline Axle 32.0" 1.145" (Less Than 600 HP) With Gun-Drilled Axles
SOTAGY11303250 31-Spline Axle 32.5" 1.130" Standard KERA 1.115" 1.130"
SOTAGY11453250 31-Spline Axle 32.5" 1.145" Optional “Tuner”/Heavy Right Side* – 1.145"
SOTAGY11653250 31-Spline Axle 32.5" 1.165" Asphalt Late Models
SOTAGY11303300 31-Spline Axle 33.0" 1.130" (700+ HP) With Gun-Drilled Axles 1.180" 1.145"
Standard KERA
SOTAGY11453300 31-Spline Axle 33.0" 1.145" Optional “Tuner” 1.130" -
SOTAGY11653300 31-Spline Axle 33.0" 1.165" Limited Asphalt Late Models
SOTAGY11803300 31-Spline Axle 33.0" 1.180" (Less Than 700 HP) With Gun-Drilled Axles
SOTAGY11653400 31-Spline Axle 34.0" 1.165" Standard KERA 1.165" 1.130"
SOTAGY11803400 31-Spline Axle 34.0" 1.180" Optional “Tuner” 1.115" -
SOTAGY12003400 31-Spline Axle 34.0" 1.200" Dirt Late Models (700+ HP) With Gun-Drilled Axles
SOTAGY11653500 31-Spline Axle 35.0" 1.165" Standard KERA 1.145" 1.200"
SOTAGY11803500 31-Spline Axle 35.0" 1.180" Optional “Tuner” 1.130" –
SOTAGY12003500 31-Spline Axle 35.0" 1.200" Sportsman & Crate Motor Dirt Late Models
SOTAGY12003600 31-Spline Axle 36.0" 1.200" With Gun-Drilled Axles
SOTAGY12003650 31-Spline Axle 36.5" 1.200" Standard KERA 1.130" 1.180"
SOTAGY12003700 31-Spline Axle 37.0" 1.200" Cars With Less Than 2.50" Of Split
Between L&R Axles (Barry Wright, Pierce, etc.)
WIDE 5 With Gun-Drilled Axles 1.165" 1.200"
Standard KERA
OVAL TRACK DRIVE PLATES Optional “Tuner” 1.145" -
Lightweight, yet durable Wide 5 drive plates are * For “heavy” or rough tracks. Also used to create wide diameter split
manufactured from aircraft quality aluminum and fit- between left and right.
ted with steel splined inserts for improved longevity.
Drive plates are mill scalloped to reduce weight and WIDE 5 OVAL TRACK
include flanged steel sleeve mounting hole bushings DRIVE PLATES FOR
for reduced distortion.
Part No. Description CAMBERED AXLES
SOTADW500 Aluminum Standard 5-Lug Drive Plate Designed for use with cambered axles, billet steel
SOTADW800 Aluminum 8-Lug Drive Plate Wide 5 drive plates are mill scalloped to reduce rotating
weight and feature steel splined inserts for improved wear
resistance. Drive plates are zinc plated for corrosion resistance.
Part No. Description
SOTADW520 Steel Articulating 5-Lug Drive Plate
SOTADW820 Steel Articulating 8-Lug Drive Plate

SuperTrapp’s exhaust outlet is actually a series of precise gaps between diffuser discs. As exhaust travels from the center of the diffuser disc toward the outside,
it moves into a larger area, creating a pressure drop; exhaust gases are drawn out or scavenged. Adding discs increases the size of the outlet, thereby reducing
back pressure, increasing top end power, racing sound level, and leaning out carburetion. By adding or subtracting discs, the power band can be quickly and easily
adjusted.
MODEL 544 DISC ONLY 5" DIFFUSER DISC PACKS
Disc-Only models depend only upon the discs for Add discs to decrease back pressure,
noise reduction and are ideal for limited space. The increase top end performance... and noise
544 models use 5" diffuser discs. level. Remove discs to lower noise level,
Part No. Description with an increase in bottom end power.
SPR544-2503 Fits 2-1/2" Diameter Pipe Part No. Description
SPR544-3003 Fits 3" Diameter Pipe SPR504-6506 6-Pack
SPR544-3503 Fits 3-1/2" Diameter Pipe SPR504-6512 12-Pack
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