Welcome to Great Plains Aircraft Supply Co!

Welcome to Great Plains Aircraft Supply Co., Inc.!

Shopping Cart

Type 1 - 1/2 VW Conversion Parts and Plans!

"Carr Twin" 1/2 VW Plans
The introduction of the "Carr Twin", as a "sawed in half VW engine", was designed by Dave Carr and was featured in the January, 1975, issue of "Sport Aviation" magazine. The "Carr Twin" was awarded the John Livingston Award for outstanding contribution to low cost flyings, as well as, the Stan Dzik Memorial Award for outstanding design contribution.

Carr Half Case above
Carr Full Case to right

The "Carr Twin" Plans offer plans for both the cut case and full case versions.


Parts are low cost and available throughout the world.

Lightweight: The crankcase is made of magnesium, 1/3 lighter than aluminum with excellent heat transfer qualities. The heads are aluminum. An 87 pound, 35hp engine is hard to beat!

Air-cooled: With both cylinders exposed to direct air stream.

Crankshaft RPM corrects for direct mounting of propellor (no need to gear down or belt drive.)

A four-stroke engine with generous bearing diameter means long life, extra reliability, and low fuel consumption.

Can be used in tractor or pusher properllor configuration.

A fun project for the mechanical craftsman!

The "Carr Twin" 1/2 VW Plans include:

Two Crankcase options: Cut case, welded or bolted together - most compact version. Full Crankcase - The quickest to build version, because no machine work is necessary on the case. Engine can be mounted directly on firewall (no motor frame required), (no oil cooler required) and the crankcase can be returned to it's 4-cylinder configuration if more horsepower is needed.

contain 13 detailed drawings, with written instructions.

Carr Twin 1/2 VW Plans . . . $30.00
Plus postage.

Engine Specifications for the Carr Twin
2-Cylinder opposed Twin 4-Cylce O.H.V.
Stroke 78mm 82mm
Bore 92mm 92mm
Displacement 1037cc 1138cc
Weight 87 lbs. * 87 lbs. *
Horsepower 35hp @ 3400 rpm 38hp @ 3400 rpm

* Full case weighs approx. 5 additional pounds.

92mm Piston & Cylinders
Stroker Connecting Rods

U-Build Exhaust Manifold Kit
Includes two exhaust welding flanges, two each 90 degree mandrel bent tubes and two each 180 degree mandrel bent tubes. Tubes are 8" long and 1 1/2" diameter.
U-build Exhaust Manifold Kit . . $39.95
Model 11 Carburetor for the 1/2 VW.
This is an updraft carburetor with mounting flange and mixture control.
Has idle air bleed screw also.
Model 11 Carb . . . $379.80
U-Build Intake Manifold Kit
Includes two flanges, four each 90 degree pieces of 8" long, 1 1/2" O.D. tubing and one 180 degree U-bend.
U-build Intake Manifold Kit . . . $44.95

To place an order: Call us at 1-402-493-6507
Inquiries can also be directed to: info@greatplainsas.com

Great Plains Aircraft Supply Co.