Durable Tri-max Bolt-in Hrb For Small Diameter Racing Clutches Gadget [uMLGZn09]

Don’t see your configuration?

Call us at 714-630-2764 or email: [email protected]

Bolts to the bellhousing.

PTT's Tri-MAX Hydraulic Release Bearing (HRB) is the most reliable, lightest, and strongest bolt-in HRB on the racecar market. Tri-MAX is designed to work with all small diameter multi-disc racing clutches and will fit Muncie, Jerico, Roltek, T-10, T-101, Saginaw & other transmissions. Tri-MAX has a full 3/4" of release travel, (the longest travel in its class) and has superbly engineered hydraulics to ensure positive, 100% clutch engagement. PTT's custom-designed, low drag, 1.6" radius face bearing is standard equipment. The smaller diameter contact reduces clutch pedal effort, while also lowering the thrust on the back of the crank! Tri-MAX works best with 5/8" or 3/4" master cylinders.

Tri-MAX is CNC manufactured to aircraft industry tolerances from high strength aluminum. All moving parts are premium hardcoat anodized for long, trouble-free life.  All Tri-MAX bearings are pressure tested to twice normal operating pressure before leaving the factory. You can bolt a Tri-MAX in with confidence knowing that it will work as advertised right out of the box. The velvety smooth clutch actuation you get from a Tri-MAX must be felt to be believed. Tri-MAX is the reason you want to run a hydraulic release bearing.

1. MAX-imum strength! Manufactured from high-strength extruded aluminum. Guaranteed for life never to break due to structural failure!
2. MAX-imum lightness! Tri-MAX weighs less than 1 pound! That's 20% to 50% less than other manufacturers' bolt-in HRB's
3. MAX-imum reliability! Built to withstand more than 3 times normal operating pressure.
4. Tri-MAX has 3/4" of bearing travel.
5. Simple bolt-in installation. No shims to adjust or complicated measuring.
6. Precision aligned for less clutch wear
7. Low-drag hydraulics guarantee complete clutch engagement
8. Includes PTT's exclusive 1.6" diameter radius faced angular contact ball bearing
9. Works best with 5/8” or 3/4” master cylinders. (the smaller master cylinder gives you lower pedal effort & better clutch control)

When will my order ship?

Click here for Hydraulic Release Bearing Catalog.

RT73271-d

RT73271

Tri-MAX Hydraulic Release Bearing Slave Cylinder

• Bolt-in Hydraulic Release Bearing (HRB) for small diameter racing clutches
• Fits a 3 disc clutch with a Chevy flywheel & flexplate
• Uses PTT’s proprietary 1.6” (40.6mm) diameter, radius face bearing
• Shortest possible height is: 70” (68.6mm) OAL, using a 1.65”  (42mm) tall Piston
• Uses interchangeable, different length pistons (ordered separately) for height adjustability
• Has a 1.39” (35.3mm) through hole, for trans snout clearance
• Bolts into bellhousing. Bellhousing must be drilled for Tri-MAX pattern.
• With an external bleeder kit
• No hydraulic supply line is included

 

RT7327224-d

RT7327224

Tri-MAX Hydraulic Release Bearing Slave Cylinder

• Bolt-in Hydraulic Release Bearing (HRB) for small diameter racing clutches
• Fits a 3 disc clutch with a Chevy flywheel & flexplate
• Uses PTT’s proprietary 1.6” (40.6mm) diameter, radius face bearing
• Shortest possible height is: 70” (68.6mm) OAL, using a 1.65”  (42mm) tall Piston
• Uses interchangeable, different length pistons (ordered separately) for height adjustability
• Has a 1.39” (35.3mm) through hole, for trans snout clearance
• Bolts into bellhousing. Bellhousing must be drilled for Tri-MAX pattern.
• With an external bleeder kit
• With a 24” (610mm) long hydraulic supply line

 

RT7327234-d

RT7327234

Tri-MAX Hydraulic Release Bearing Slave Cylinder

• Bolt-in Hydraulic Release Bearing (HRB) for small diameter racing clutches
• Fits a 3 disc clutch with a Chevy flywheel & flexplate
• Uses PTT’s proprietary 1.6” (40.6mm) diameter, radius face bearing
• Shortest possible height is: 70” (68.6mm) OAL, using a 1.65”  (42mm) tall Piston
• Uses interchangeable, different length pistons (ordered separately) for height adjustability
• Has a 1.39” (35.3mm) through hole, for trans snout clearance
• Bolts into bellhousing. Bellhousing must be drilled for Tri-MAX pattern.
• With an external bleeder kit
• With a 34” (865mm) long hydraulic supply line

 

RT73281-d

RT73281

Tri-MAX Hydraulic Release Bearing Slave Cylinder

• Bolt-in Hydraulic Release Bearing (HRB) for small diameter racing clutches
• Fits a 3 disc clutch with a Chevy flywheel & reverse mount ring gear
• Uses PTT’s proprietary 1.6” (40.6mm) diameter, radius face bearing
• Shortest possible height is: 85” (72.4mm) OAL, using a 1.80”  (45.7mm) tall Piston
• Uses interchangeable, different length pistons (ordered separately) for height adjustability
• Has a 1.39” (35.3mm) through hole, for trans snout clearance
• Bolts into bellhousing. Bellhousing must be drilled for Tri-MAX pattern.
• With an external bleeder kit
• No hydraulic supply line is included

 

RT7328224-d

RT7328224

Tri-MAX Hydraulic Release Bearing Slave Cylinder

• Bolt-in Hydraulic Release Bearing (HRB) for small diameter racing clutches
• Fits a 3 disc clutch with a Chevy flywheel & reverse mount ring gear
• Uses PTT’s proprietary 1.6” (40.6mm) diameter, radius face bearing
• Shortest possible height is: 85” (72.4mm) OAL, using a 1.80”  (45.7mm) tall Piston
• Uses interchangeable, different length pistons (ordered separately) for height adjustability
• Has a 1.39” (35.3mm) through hole, for trans snout clearance
• Bolts into bellhousing. Bellhousing must be drilled for Tri-MAX pattern.
• With an external bleeder kit
• With a 24” (610mm) long hydraulic supply line

 

RT7328234-d

RT7328234

Tri-MAX Hydraulic Release Bearing Slave Cylinder

• Bolt-in Hydraulic Release Bearing (HRB) for small diameter racing clutches
• Fits a 3 disc clutch with a Chevy flywheel & reverse mount ring gear
• Uses PTT’s proprietary 1.6” (40.6mm) diameter, radius face bearing
• Shortest possible height is: 85” (72.4mm) OAL, using a 1.80”  (45.7mm) tall Piston
• Uses interchangeable, different length pistons (ordered separately) for height adjustability
• Has a 1.39” (35.3mm) through hole, for trans snout clearance
• Bolts into bellhousing. Bellhousing must be drilled for Tri-MAX pattern.
• With an external bleeder kit
• With a 34” (865mm) long hydraulic supply line

 

RT73301-d

RT73301

Tri-MAX Hydraulic Release Bearing Slave Cylinder

• Bolt-in Hydraulic Release Bearing (HRB) for small diameter racing clutches
• Fits a 3 disc clutch with a Chevy flywheel, reverse mount ring gear, & 1/4” thick motor plate
• Uses PTT’s proprietary 1.6” (40.6mm) diameter, radius face bearing
• Shortest possible height is: 0” (76.2mm) OAL, using a 1.95”  (49.5mm) tall Piston
• Uses interchangeable, different length pistons (ordered separately) for height adjustability
• Has a 1.39” (35.3mm) through hole, for trans snout clearance
• Bolts into bellhousing. Bellhousing must be drilled for Tri-MAX pattern.
• With an external bleeder kit
• No hydraulic supply line is included

 

RT7330224-d

RT7330224

Tri-MAX Hydraulic Release Bearing Slave Cylinder

• Bolt-in Hydraulic Release Bearing (HRB) for small diameter racing clutches
• Fits a 3 disc clutch with a Chevy flywheel, reverse mount ring gear, & 1/4” thick motor plate
• Uses PTT’s proprietary 1.6” (40.6mm) diameter, radius face bearing
• Shortest possible height is: 0” (76.2mm) OAL, using a 1.95”  (49.5mm) tall Piston
• Uses interchangeable, different length pistons (ordered separately) for height adjustability
• Has a 1.39” (35.3mm) through hole, for trans snout clearance
• Bolts into bellhousing. Bellhousing must be drilled for Tri-MAX pattern.
• With an external bleeder kit
• With a 24” (610mm) long hydraulic supply line

 

RT7330234-d

RT7330234

Tri-MAX Hydraulic Release Bearing Slave Cylinder

• Bolt-in Hydraulic Release Bearing (HRB) for small diameter racing clutches
• Fits a 3 disc clutch with a Chevy flywheel, reverse mount ring gear, & 1/4” thick motor plate
• Uses PTT’s proprietary 1.6” (40.6mm) diameter, radius face bearing
• Shortest possible height is: 0” (76.2mm) OAL, using a 1.95”  (49.5mm) tall Piston
• Uses interchangeable, different length pistons (ordered separately) for height adjustability
• Has a 1.39” (35.3mm) through hole, for trans snout clearance
• Bolts into bellhousing. Bellhousing must be drilled for Tri-MAX pattern.
• With an external bleeder kit
• With a 34” (865mm) long hydraulic supply line

 

RT73311-d

RT73311

Tri-MAX Hydraulic Release Bearing Slave Cylinder

• Bolt-in Hydraulic Release Bearing (HRB) for small diameter racing clutches
• Fits a 2 disc clutch with a Chevy flywheel & reverse mount ring gear
• Uses PTT’s proprietary 1.6” (40.6mm) diameter, radius face bearing
• Shortest possible height is: 15” (80.0mm) OAL, using a 2.10”  (53.3mm) tall Piston
• Uses interchangeable, different length pistons (ordered separately) for height adjustability
• Has a 1.39” (35.3mm) through hole, for trans snout clearance
• Bolts into bellhousing. Bellhousing must be drilled for Tri-MAX pattern.
• With an external bleeder kit
• No hydraulic supply line is included

 

RT7331224-d

RT7331224

Tri-MAX Hydraulic Release Bearing Slave Cylinder

• Bolt-in Hydraulic Release Bearing (HRB) for small diameter racing clutches
• Fits a 2 disc clutch with a Chevy flywheel & reverse mount ring gear
• Uses PTT’s proprietary 1.6” (40.6mm) diameter, radius face bearing
• Shortest possible height is: 15” (80.0mm) OAL, using a 2.10”  (53.3mm) tall Piston
• Uses interchangeable, different length pistons (ordered separately) for height adjustability
• Has a 1.39” (35.3mm) through hole, for trans snout clearance
• Bolts into bellhousing. Bellhousing must be drilled for Tri-MAX pattern.
• With an external bleeder kit
• With a 24” (610mm) long hydraulic supply line

 

RT7331234-d

RT7331234

Tri-MAX Hydraulic Release Bearing Slave Cylinder

• Bolt-in Hydraulic Release Bearing (HRB) for small diameter racing clutches
• Fits a 2 disc clutch with a Chevy flywheel & reverse mount ring gear
• Uses PTT’s proprietary 1.6” (40.6mm) diameter, radius face bearing
• Shortest possible height is: 15” (80.0mm) OAL, using a 2.10”  (53.3mm) tall Piston
• Uses interchangeable, different length pistons (ordered separately) for height adjustability
• Has a 1.39” (35.3mm) through hole, for trans snout clearance
• Bolts into bellhousing. Bellhousing must be drilled for Tri-MAX pattern.
• With an external bleeder kit
• With a 34” (865mm) long hydraulic supply line

 

RT73331-d

RT73331

Tri-MAX Hydraulic Release Bearing Slave Cylinder

• Bolt-in Hydraulic Release Bearing (HRB) for small diameter racing clutches
• Fits a 2 disc clutch with a Chevy flywheel, reverse mount ring gear, & 1/4” thick motor plate
• Uses PTT’s proprietary 1.6” (40.6mm) diameter, radius face bearing
• Shortest possible height is: 30” (83.8mm) OAL, using a 2.25”  (57.1mm) tall Piston
• Uses interchangeable, different length pistons (ordered separately) for height adjustability
• Has a 1.39” (35.3mm) through hole, for trans snout clearance
• Bolts into bellhousing. Bellhousing must be drilled for Tri-MAX pattern.
• With an external bleeder kit
• No hydraulic supply line is included

 

RT7333224-d

RT7333224

Tri-MAX Hydraulic Release Bearing Slave Cylinder

• Bolt-in Hydraulic Release Bearing (HRB) for small diameter racing clutches
• Fits a 2 disc clutch with a Chevy flywheel, reverse mount ring gear, & 1/4” thick motor plate
• Uses PTT’s proprietary 1.6” (40.6mm) diameter, radius face bearing
• Shortest possible height is: 30” (83.8mm) OAL, using a 2.25”  (57.1mm) tall Piston
• Uses interchangeable, different length pistons (ordered separately) for height adjustability
• Has a 1.39” (35.3mm) through hole, for trans snout clearance
• Bolts into bellhousing. Bellhousing must be drilled for Tri-MAX pattern.
• With an external bleeder kit
• With a 24” (610mm) long hydraulic supply line

 

RT7333234-d

RT7333234

Tri-MAX Hydraulic Release Bearing Slave Cylinder

• Bolt-in Hydraulic Release Bearing (HRB) for small diameter racing clutches
• Fits a 2 disc clutch with a Chevy flywheel, reverse mount ring gear, & 1/4” thick motor plate
• Uses PTT’s proprietary 1.6” (40.6mm) diameter, radius face bearing
• Shortest possible height is: 30” (83.8mm) OAL, using a 2.25”  (57.1mm) tall Piston
• Uses interchangeable, different length pistons (ordered separately) for height adjustability
• Has a 1.39” (35.3mm) through hole, for trans snout clearance
• Bolts into bellhousing. Bellhousing must be drilled for Tri-MAX pattern.
• With an external bleeder kit
• With a 34” (865mm) long hydraulic supply line

 

RT73341-d

RT73341

Tri-MAX Hydraulic Release Bearing Slave Cylinder

• Bolt-in Hydraulic Release Bearing (HRB) for small diameter racing clutches
• Fits a 1 disc clutch with a Chevy flywheel & reverse mount ring gear
• Uses PTT’s proprietary 1.6” (40.6mm) diameter, radius face bearing
• Shortest possible height is: 45” (87.6mm) OAL, using a 2.40”  (60.9mm) tall Piston
• Uses interchangeable, different length pistons (ordered separately) for height adjustability
• Has a 1.39” (35.3mm) through hole, for trans snout clearance
• Bolts into bellhousing. Bellhousing must be drilled for Tri-MAX pattern.
• With an external bleeder kit
• No hydraulic supply line is included

 

RT7334224-d

RT7334224

Tri-MAX Hydraulic Release Bearing Slave Cylinder

• Bolt-in Hydraulic Release Bearing (HRB) for small diameter racing clutches
• Fits a 1 disc clutch with a Chevy flywheel & reverse mount ring gear
• Uses PTT’s proprietary 1.6” (40.6mm) diameter, radius face bearing
• Shortest possible height is: 45” (87.6mm) OAL, using a 2.40”  (60.9mm) tall Piston
• Uses interchangeable, different length pistons (ordered separately) for height adjustability
• Has a 1.39” (35.3mm) through hole, for trans snout clearance
• Bolts into bellhousing. Bellhousing must be drilled for Tri-MAX pattern.
• With an external bleeder kit
• With a 24” (610mm) long hydraulic supply line

 

RT7324234-d

RT7334234

Tri-MAX Hydraulic Release Bearing Slave Cylinder

• Bolt-in Hydraulic Release Bearing (HRB) for small diameter racing clutches
• Fits a 1 disc clutch with a Chevy flywheel & reverse mount ring gear
• Uses PTT’s proprietary 1.6” (40.6mm) diameter, radius face bearing
• Shortest possible height is: 45” (87.6mm) OAL, using a 2.40”  (60.9mm) tall Piston
• Uses interchangeable, different length pistons (ordered separately) for height adjustability
• Has a 1.39” (35.3mm) through hole, for trans snout clearance
• Bolts into bellhousing. Bellhousing must be drilled for Tri-MAX pattern.
• With an external bleeder kit
• With a 34” (865mm) long hydraulic supply line

 

RT73361-d

RT73361

Tri-MAX Hydraulic Release Bearing Slave Cylinder

• Bolt-in Hydraulic Release Bearing (HRB) for small diameter racing clutches
• Fits a 1 disc clutch with a Chevy flywheel, reverse mount ring gear, & 1/4” thick motor plate
• Uses PTT’s proprietary 1.6” (40.6mm) diameter, radius face bearing
• Shortest possible height is: 60” (91.4mm) OAL, using a 2.55”  (64.8mm) tall Piston
• Uses interchangeable, different length pistons (ordered separately) for height adjustability
• Has a 1.39” (35.3mm) through hole, for trans snout clearance
• Bolts into bellhousing. Bellhousing must be drilled for Tri-MAX pattern.
• With an external bleeder kit
• No hydraulic supply line is included

 

RT7336224-d

RT7336224

Tri-MAX Hydraulic Release Bearing Slave Cylinder

• Bolt-in Hydraulic Release Bearing (HRB) for small diameter racing clutches
• Fits a 1 disc clutch with a Chevy flywheel, reverse mount ring gear, & 1/4” thick motor plate
• Uses PTT’s proprietary 1.6” (40.6mm) diameter, radius face bearing
• Shortest possible height is: 60” (91.4mm) OAL, using a 2.55”  (64.8mm) tall Piston
• Uses interchangeable, different length pistons (ordered separately) for height adjustability
• Has a 1.39” (35.3mm) through hole, for trans snout clearance
• Bolts into bellhousing. Bellhousing must be drilled for Tri-MAX pattern.
• With an external bleeder kit
• With a 24” (610mm) long hydraulic supply line

 

RT7336234-d

RT7336234

Tri-MAX Hydraulic Release Bearing Slave Cylinder

• Bolt-in Hydraulic Release Bearing (HRB) for small diameter racing clutches
• Fits a 1 disc clutch with a Chevy flywheel, reverse mount ring gear, & 1/4” thick motor plate
• Uses PTT’s proprietary 1.6” (40.6mm) diameter, radius face bearing
• Shortest possible height is: 60” (91.4mm) OAL, using a 2.55”  (64.8mm) tall Piston
• Uses interchangeable, different length pistons (ordered separately) for height adjustability
• Has a 1.39” (35.3mm) through hole, for trans snout clearance
• Bolts into bellhousing. Bellhousing must be drilled for Tri-MAX pattern.
• With an external bleeder kit
• With a 34” (865mm) long hydraulic supply line

 

RT73371-d

RT73371

Tri-MAX Hydraulic Release Bearing Slave Cylinder

• Bolt-in Hydraulic Release Bearing (HRB) for small diameter racing clutches
• Fits a 1 disc clutch with a Chevy flywheel, reverse mount ring gear, & 3/8” thick motor plate
• Uses PTT’s proprietary 1.6” (40.6mm) diameter, radius face bearing
• Shortest possible height is: 75” (95.3mm) OAL, using a 2.70”  (68.6mm) tall Piston
• Uses interchangeable, different length pistons (ordered separately) for height adjustability
• Has a 1.39” (35.3mm) through hole, for trans snout clearance
• Bolts into bellhousing. Bellhousing must be drilled for Tri-MAX pattern.
• With an external bleeder kit
• No hydraulic supply line is included

 

 

RT7337224-d

RT7337224

Tri-MAX Hydraulic Release Bearing Slave Cylinder

• Bolt-in Hydraulic Release Bearing (HRB) for small diameter racing clutches
• Fits a 1 disc clutch with a Chevy flywheel, reverse mount ring gear, & 3/8” thick motor plate
• Uses PTT’s proprietary 1.6” (40.6mm) diameter, radius face bearing
• Shortest possible height is: 75” (95.3mm) OAL, using a 2.70”  (68.6mm) tall Piston
• Uses interchangeable, different length pistons (ordered separately) for height adjustability
• Has a 1.39” (35.3mm) through hole, for trans snout clearance
• Bolts into bellhousing. Bellhousing must be drilled for Tri-MAX pattern.
• With an external bleeder kit
• With a 24” (610mm) long hydraulic supply line

 

RT7337234-d

RT7337234

Tri-MAX Hydraulic Release Bearing Slave Cylinder

• Bolt-in Hydraulic Release Bearing (HRB) for small diameter racing clutches
• Fits a 1 disc clutch with a Chevy flywheel, reverse mount ring gear, & 3/8” thick motor plate
• Uses PTT’s proprietary 1.6” (40.6mm) diameter, radius face bearing
• Shortest possible height is: 75” (95.3mm) OAL, using a 2.70”  (68.6mm) tall Piston
• Uses interchangeable, different length pistons (ordered separately) for height adjustability
• Has a 1.39” (35.3mm) through hole, for trans snout clearance
• Bolts into bellhousing. Bellhousing must be drilled for Tri-MAX pattern.
• With an external bleeder kit
• With a 34” (865mm) long hydraulic supply line

 

RT73116-d

RT73116

Tri-MAX Hydraulic Release Bearing Slave Cylinder

Replacement Piston & Bearing

• Piston & Bearing Only, 1.65” (41.9mm) overall length
• Uses PTT’s proprietary 1.6” (40.6mm) diameter, radius face bearing
• Has a 1.39” (35.3mm) through hole, for trans snout clearance

 

RT73118-d

RT73118

Tri-MAX Hydraulic Release Bearing Slave Cylinder

Replacement Piston & Bearing

• Piston & Bearing Only, 1.80” (45.7mm) overall length
• Uses PTT’s proprietary 1.6” (40.6mm) diameter, radius face bearing
• Has a 1.39” (35.3mm) through hole, for trans snout clearance

 

RT73119-d

RT73119

Tri-MAX Hydraulic Release Bearing Slave Cylinder

Replacement Piston & Bearing

• Piston & Bearing Only, 1.95” (49.5mm) overall length
• Uses PTT’s proprietary 1.6” (40.6mm) diameter, radius face bearing
• Has a 1.39” (35.3mm) through hole, for trans snout clearance

 

RT73121-d

RT73121

Tri-MAX Hydraulic Release Bearing Slave Cylinder

Replacement Piston & Bearing

• Piston & Bearing Only, 2.10” (53.3mm) overall length
• Uses PTT’s proprietary 1.6” (40.6mm) diameter, radius face bearing
• Has a 1.39” (35.3mm) through hole, for trans snout clearance

 

RT73122-d

RT73122

Tri-MAX Hydraulic Release Bearing Slave Cylinder

Replacement Piston & Bearing

• Piston & Bearing Only, 2.25” (57.1mm) overall length
• Uses PTT’s proprietary 1.6” (40.6mm) diameter, radius face bearing
• Has a 1.39” (35.3mm) through hole, for trans snout clearance

 

RT73124-d

RT73124

Tri-MAX Hydraulic Release Bearing Slave Cylinder

Replacement Piston & Bearing

• Piston & Bearing Only, 2.40” (60.9mm) overall length
• Uses PTT’s proprietary 1.6” (40.6mm) diameter, radius face bearing
• Has a 1.39” (35.3mm) through hole, for trans snout clearance

 

RT73125-d

RT73125

Tri-MAX Hydraulic Release Bearing Slave Cylinder

Replacement Piston & Bearing

• Piston & Bearing Only, 2.55” (64.7mm) overall length
• Uses PTT’s proprietary 1.6” (40.6mm) diameter, radius face bearing
• Has a 1.39” (35.3mm) through hole, for trans snout clearance

 

RT73127-d

RT73127

Tri-MAX Hydraulic Release Bearing Slave Cylinder

Replacement Piston & Bearing

• Piston & Bearing Only, 2.70” (68.6mm) overall length
• Uses PTT’s proprietary 1.6” (40.6mm) diameter, radius face bearing
• Has a 1.39” (35.3mm) through hole, for trans snout clearance

 

RH7112-d

RH7112

Tri-MAX Hydraulic Release Bearing Slave Cylinder

Replacement Bleeder Kit

• This kit includes one -3 Union, and one -3 S.S. Braided Line, 8” long
• The bleeder screw originally With the Tri-MAX is re-used

 

RT7313-d

RT7313

Tri-MAX Hydraulic Release Bearing Slave Cylinder

 Rebuild Kit

• Includes all parts needed to rebuild your Tri-MAX
• All O-Rings
• One Wiper Seal
• Two -3 Unions

 

RM001-d

RM001

Hydraulic Release Bearing Slave Cylinder

Replacement Bearing

• Bearing Only
• PTT’s proprietary 1.6” (40.6mm) contact diameter, radius face bearing
• I.D.: 1.575” (40mm) 
• Height: 725” (18.4 mm)
• O.D.: 2.530” (64.2 mm)
• Smallest contact diameter which will still release PTT clutches
• Offers reduced clutch pedal effort, through maximum leverage
• For use with 4.5”, 5.5”, & 7-1/4” racing clutches