Outdrives and Accessories - Bravo Extension Boxes

This is a direct replacement for the flanged shaft (Mercury OEM's #939064, 93906A2, 8M0192274) inside the bell housing for a driveline setup with a Bravo drive. They are made from 4340 chromoly and actually weigh 0.2lbs heavier than the stock ones even though they are exactly the same dimensions. Made in the USA. 

Extension Box Kit 13.5° Transom Angle x 12.000” Straight Back, Black

IMCO Standard Height Extension Box Only

This is the most advanced, easy to install, state of the art standard box on the market today. The torsional drive shaft helps cushion the shock to the outdrive when shifting in and out of gear, and on and off throttle operations. Inferior designed competitor's boxes use a drive shaft that is solid mounted to the flywheel, doing away with your coupler. Their units literally hammer the internal components in your drive, which rapidly accelerates failure.

IMCO's torsional driveshaft and the stock MerCruiser rubber coupler are designed to absorb shock resulting from extreme high performance applications and rough water conditions.

356 T-6 cast aluminum transom motor mount brackets available for both neutral and 3"lift extension boxes.

Lightweight super strong cast 356 T-6 aluminum extension boxes, available in 12" neutral set-back or 12" set-back with 3" lift.

356 T-6 aluminum side mount steering brackets allows ample mounting clearance for optimum K-Plane placement - clears most exhaust ports, swim brackets, etc. - keeps rams on pivot center line.

EXTENSION BOX KITS "AVAILABLE IN A 3.000" LIFT"

Extension Box Kit 13.5° Transom Angle x 12.000” Straight Back, Silver

IMCO Standard Height Extension Box Only

This is the most advanced, easy to install, state of the art standard box on the market today. The torsional drive shaft helps cushion the shock to the outdrive when shifting in and out of gear, and on and off throttle operations. Inferior designed competitor's boxes use a drive shaft that is solid mounted to the flywheel, doing away with your coupler. Their units literally hammer the internal components in your drive, which rapidly accelerates failure.

IMCO's torsional driveshaft and the stock MerCruiser rubber coupler are designed to absorb shock resulting from extreme high performance applications and rough water conditions.

356 T-6 cast aluminum transom motor mount brackets available for both neutral and 3"lift extension boxes.

Lightweight super strong cast 356 T-6 aluminum extension boxes, available in 12" neutral set-back or 12" set-back with 3" lift.

356 T-6 aluminum side mount steering brackets allows ample mounting clearance for optimum K-Plane placement - clears most exhaust ports, swim brackets, etc. - keeps rams on pivot center line.

EXTENSION BOX KITS "AVAILABLE IN A 3.000" LIFT"

Dual External Hydraulic Steering For Bravo One Stern Drives

IMCO's external hydraulic steering for the MerCruiser Bravo One has been designed, engineered and tested to eliminate side-to-side drive unit "play", a major contributor to high speed chine walking IMCO's power steering system is ultra heavy-duty throughout. The  IMCO steering systems are easily installed and priced more affordably than other less efficient alternatives. Includes an extension box kit.

Note: These kits contain non-assembled rubber hoses and brass fittings See steering component section for stainless steel braided line options.

For parts list, and to buy replacement parts click here

Dual External Hydraulic Steering For 2 Bravo One Stern Drives

IMCO's external hydraulic steering for the MerCruiser Bravo One has been designed, engineered and tested to eliminate side-to-side drive unit "play", a major contributor to high speed chine walking IMCO's power steering system is ultra heavy-duty throughout. The  IMCO steering systems are easily installed and priced more affordably than other less efficient alternatives. Includes an extension box kit.

Note: These kits contain non-assembled rubber hoses and brass fittings See steering component section for stainless steel braided line options.

Kit includes Tie bar up to 18" at no extra cost. Tie Bars longer than 18" will have additional price per inch. Please type the exact length of the tie bar you need (example: 34.5") and then select the price option from the drop drown (from previous example, choose 35" for a 34.5" tie bar) 

For parts list, and to buy replacement parts click here

Dual External Hydraulic Steering For 2 Bravo One Stern Drives

IMCO's external hydraulic steering for the MerCruiser Bravo One has been designed, engineered and tested to eliminate side-to-side drive unit "play", a major contributor to high speed chine walking IMCO's power steering system is ultra heavy-duty throughout. The  IMCO steering systems are easily installed and priced more affordably than other less efficient alternatives. Includes an extension box kit.

Note: These kits contain non-assembled rubber hoses and brass fittings See steering component section for stainless steel braided line options.

Kit includes Tie bar up to 18" at no extra cost. Tie Bars longer than 18" will have additional price per inch. Please type the exact length of the tie bar you need (example: 34.5") and then select the price option from the drop drown (from previous example, choose 35" for a 34.5" tie bar) 

For parts list, and to buy replacement parts click here

Extension Box Side Mount Bracket Black

Extension Box Side Mount Bracket Silver

MayFair 4340 chromoly heat treated Slip-on u-joint extension shaft for all Bravo drives with stand off boxes. This extension shaft slips over your stock Bravo spline output shaft , no need to remove your stock mercury spline output shaft for a quick and easy installation.

Extension Box Drive Shaft 1.062” Bearing Cap Dia

Extension Box Drive Shaft 1.077” Bearing Cap Dia

Extension Box Drive Shaft 1.217” Bearing Cap Dia

Extension Box Drive Shaft 1.328” Bearing Cap Dia

Extension Box Drive Shaft Alignment Tool 1.370” x 39.000” OAL