137-9631 Single Bravo / Dual Ram Sterndrive Extension Box Kit The Mayfair standoff box kit is the most advanced, easy to install, state of the art system on the market today. The torsional drive shaft helps cushion the shock to the outdrive when shifting in and out of gear. Mayfairs’ torsional driveshaft and the Mercruiser high performance coupler are designed to absorb shock to the Bravo outdrive. All Mayfair extension boxes are manufactured from356 T-6 cast aluminum, CNC machined for accuracy, and then hard anodized for supreme corrosion resistance. This kit includes: - Extension Standoff Boxes
- Backing Plates
- Rear Engine Mount Pads
- Extended Bravo Drive Lines
- Extension Box Mounting Hardware
- Dual Cylinder Mayfair Add-On Hydraulic Steering Kit
NOTE: When running a standoff box, you must use a twin ram full power steering system.
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137-9630 Single Bravo Sterndrive Extension Box Kit The Mayfair standoff box kit is the most advanced, easy to install, state of the art system on the market today. The torsional drive shaft helps cushion the shock to the outdrive when shifting in and out of gear. Mayfairs’ torsional driveshaft and the Mercruiser high performance coupler are designed to absorb shock to the Bravo outdrive. All Mayfair extension boxes are manufactured from 356 T-6 cast aluminum, CNC machined for accuracy, and then hard anodized for supreme corrosion resistance. This kit includes: - Extension Standoff Box
- Backing Plate
- Rear Engine Mount Pads
- Extended Bravo Drive Line
- Extension Box Mounting Hardware
NOTE: When running a standoff box, you must use a twin ram full power steering system. This Kit does NOT include Steering.
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This Part has options, please click the button below to order.
421-DS + Option(s) U-Joint Extension Box Drive Shaft
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137-9633 Dual (Twin) Bravo / Dual Ram Sterndrive Extension Box Kit The Mayfair standoff box kit is the most advanced, easy to install, state of the art system on the market today. The torsional drive shaft helps cushion the shock to the outdrive when shifting in and out of gear. Mayfairs’ torsional driveshaft and the Mercruiser high performance coupler are designed to absorb shock to the Bravo outdrive. All Mayfair extension boxes are manufactured from 356 T-6 cast aluminum, CNC machined for accuracy, and then hard anodized for supreme corrosion resistance. This kit includes: - Extension Standoff Boxes
- Backing Plates
- Rear Engine Mount Pads
- Extended Bravo Drive Linse
- Extension Box Mounting Hardware
- Dual Cylinder Mayfair Add-On Hydraulic Steering Kit
NOTE: When running a standoff box, you must use a twin ram full power steering system.
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137-9632 Dual Engine (Twin) Bravo Sterndrive Extension Box Kit The Mayfair standoff box kit is the most advanced, easy to install, state of the art system on the market today. The torsional drive shaft helps cushion the shock to the outdrive when shifting in and out of gear. Mayfairs’ torsional driveshaft and the Mercruiser high performance coupler are designed to absorb shock to the Bravo outdrive. All Mayfair extension boxes are manufactured from356 T-6 cast aluminum, CNC machined for accuracy, and then hard anodized for supreme corrosion resistance. This kit includes: - Extension Standoff Box
- Backing Plate
- Rear Engine Mount Pads
- Extended Bravo Drive Line
- Extension Box Mounting Hardware
NOTE: When running a standoff box, you must use a twin ram full power steering system. This kit does NOT include Steering.
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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
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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.
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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.
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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.
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