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Competition Marine Designs, Inc.
Ph: (386)330-2420
andybrownprops
@gmail.com


Features
Bushed Drum Housing

Double bushed 7075-T6 Connecting rod

Dynamically balanced Drum Valve

Large cooling capacity for Sport hydro's & Vee's

3 Transfers with Piston Ports

The MAC21 has the same bolt pattern as Novarossi, CMB and Picco

Heavy duty crankshaft bearings
Specifications
Bore: 16.17mm
Stroke: 16.98mm
Rod Length: 31mm
Displacement: 3.49cc
Carburator: 9.0mm
Std. Plug head
Turbo head
- Optional
RPM: 28,000 - 36,000
Horse Power: 2.2 - 2.9
Current Records
IMPBA 21Hydro 1/3 mi. Oval - 18.86 sec., 63.62 mph.

NAMBA Sport 21 Hydro 1 mi. racing record - 88.79 sec.

IMPBA 21 Mono 1/3 mi. Oval - 26.49 sec. 45.29 mph.

IMPBA US-1 Champion

NAMBA National Champion

Recommondations
Use Brown 21 parabolic pipe set at 8.0" (cylinder center to weld).

Use with MAC 14mm ( large O.D.) header.

Head clearance - .008"

Nitro - 60%
Parts & Price List
CLICK HERE to open our price list for the MAC 21 engine, and components.

To view our price list, you must have Adobe Acrobat PDF Reader installed on your computer system. If you do not have it installed, CLICK HERE to download it for FREE.

Mac 21 | Mac 45 | Mac 67 | Mac 84

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