Prop Extension Part Number
_____x_____- ______E - ______P ______- SAE______ - ______ - _______
(1) (2) (3) (4)
(2) Diameter of prop side of extension (5", 6", or 7")
(3) Engine bolt - 8mm, 3/8, 7/16, or 1/2
(4) Prop bolt - 8mm, 3/8, 7/16, or 1/2
(5) thr or non (threaded or non-threaded lugs installed in extension
(6) SAE 1 (4.375 BC, 3/8" bolt), SAE 2 (4.750 BC, 3/8" bolt), SAE 5 (4.750 BC, 7/16" bolt) or SAE 6 (4.750 BC, 1/2" bolt)
(8) Prop - specify wood, composite, metal, ground adjustable or constant speed metal
Example: 4x7 - 7/16E - 3/8P thr - S2 - Lyc O320 - wood
ENGINES: Prices and the above part number apply only to extensions for the following engines: Continental O200, Lycoming O235, O320, O360, O540. Certain applications may entail a customizing charge.
HIGH HP ENGINES (150 AND UP): 7" diameter prop side is strongly recommended for O320 engines running wood props. It is required for O360 engines (or larger) running wood props. The 7" diameter has been in use with wood props for at least 30 years, as a response to loss of bolt torque at higher horsepowers, i.e. 150 hp and above. Benefits of the larger diameter include an increase in grip area between the faces by over 30%, and much better distribution of the torque over the face of the wood prop, thus preventing damage and distortion to the face of the wood prop, which then results in better blade tracking. These are serious advantages. The weight differential between 6" and 7" diameter extension is 5 ounces.
LYC O320: Note that your engine bolt is either 3/8 or 7/16. You must check the inside of the lug in your crankshaft flange, and specify 3/8E or 7/16E in the part number. See note above, regarding High hp.
LYC O235: Note that your engine's bolt circle diameter may be either SAE-1 (4.375") or SAE-2 (4.75"). You must check your engine, and specify S1 or S2 in the part number above.
CONT - O200: For 0-200, you may choose 5.5" diameter on the engine side of prop extension; add $14 to price of extension.
CONT - O200D: An adapter is available to change the bolt circle from 4" to 4.375". It has 3/8" drive lugs, allowing the use of an O-200 prop. $347
CONT - O240: The longest extension available for this engine is the 6" length. The shortest available is the 12-hole 2" length. The price is $80 more than the standard corresponding extension. For exact price and availability, please call to discuss the prop side of the extension. Other lengths may be available, depending on the application.
PROPS: The above part number applies only to props which mate to the following engines: Continental O200, Lycoming O235, O320, O360, O540. Certain applications may entail a customizing charge.
CONSTANT SPEED PROP: If prop is a constant speed, please measure depth of counterbore at all 6 bolt hole positions; add $63 to price of extension.
NON-STANDARD ENGINES AND/OR NON-STANDARD PROPS: Please call for price and availability.
VISA, MASTERCARD and Personal checks are gladly accepted.