Outdrives and Accessories - Bravo Extension Boxes

U-Joint Extension Box Drive Shaft
Starting From:
$706.50

This Part has options, please click the button below to order.

U-Joint Extension Box Drive Shaft

421-DS + Option(s)

U-Joint Extension Box Drive Shaft


IMCO Standard Height Extension Box Only
Your Price:
$1,799.99

Standard Height Extension Box Only

421-TEB

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.

IMCO Standard Height Extension Box Only

Standard Height Extension Box with Torsional Drive Line Neutral
Your Price:
$2,849.99

Standard Height Extension Box with Torsional Drive Line Neutral

421-TEBK

IMCO Standard Height Extension Box with Torsional Drive Line Neutral

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.

Kit includes Stand off Box, Torsional Drive Line and Neutral Mount Bracket. Steering Arms sold separately.


Extension Box with Torsional Drive Line and 3" Raised Inner Transom Assembly
Your Price:
$2,849.97

Extension Box with Torsional Drive Line and 3" Raised Inner Transom Assembly

421-TEBK1

IMCO 3" Higher Extension Box with Torsional Drive Line and 3" Raised Inner Transom Assembly

    Kit includes:
  • Stand off Box
  • Torsional Drive Line
  • 3" Raised Bracket

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.

Note: Steering Arms sold separately.


Ram Bracket Left
Your Price:
$459.99

Ram Bracket Left

421-WP-8-L

Ram Bracket Left


Ram Bracket Right
Your Price:
$459.99

Ram Bracket Right

421-WP-8-R

Ram Bracket Right


Offshore Race Upgrade Kit for Mayfair Extension Boxes
Your Price:
$1,999.99

Offshore Race Upgrade Kit for Mayfair Extension Boxes

137-9634

Offshore Race Upgrade Kit for Mayfair Extension Boxes

The upgrade kit is recommended only for all out race applications with high horsepower engines.

This kit will come with:

  • a billet bearing carrier
  • a power take off for the crankshaft
  • a splined flange to connect the Bravo drive and driveshaft assembly together.

NOTE: This is not recommended for pleasure boats.


Splined Coupler
Your Price:
$459.99

Splined Coupler

137-9647

Splined Coupler