Super 661 New HD Muncie Case

New case upgrade for all Muncie M20, M21 and M22 4 speed transmissions

Main Product Image

Sealed Bearing, countershaft, thrust washers, mounting hardware, gaskets all included.

Feature 1
Front Case Sealing

Full size 307 sealed bearing and countershaft stabilzer button

Feature 2
Streamlined Design

Zero Leak Gold fill and drain plugs, number stamping pad. Smooth engineering.

Feature 3
Bronze Thrust Washers

Replaceable bronze thrust washers included.

Feature 4
Vent and Oil Pump Ports 

Optional oil pump return and case vent ports. Dual dowel locations for side cover.  

Feature 5
Rear Case Vent Pass thru 

Balanced case half venting when using our alloy or iron midplates.  

Feature 6
V-Process Casting

Superior surface finish, tighter tolerances, excellent dimensional accuracy. 

Feature 7
1/2 NPT Oil Return Port 

Return port positioned correctly over maindrive section.

Feature 8
Optional Billet Sidecover

Uses dual dowel pins for superior cover location with the S-661 case.

Feature 9
Oversize Mounting Ears

Spot faced surfaces allow for superior clamping with new supplied hardware.

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