Crosley Engine Family Tree - CoBra Years

Crosley CoBra - 1945 to 1949

CoBra - COpper BRAzed

Developed for the government, but I'm sure Powel Crosley already had the end of the war in mind when he started developing what would become the "The Mighty Tin".

The transition from stationary engine to car engine in 1946 was not without trouble. The military engine only had to run a set number of hours then it was discarded. Running continuously it doesn't take long to put the number hours that could take years in normal car use. Valve trains had to be reworked for variable speed, coatings on the cylinder walls had to be improved to take more temperature cycles and more abusive and cheaper antifreeze substitutes.

The CoBra was under continues development and was a good 60,000+ mile engine (if properly maintained) when it was abandoned for cast iron. CoBra engines fall into two groups. The early engines had straight cut tower shaft gears and a painted block (switch to spiral cut gear came before galvinized block). The later had a spiral cut tower gear and a galvanized coated block.

Many CoBra engines not only survived but a growing number are being restored and run as display engines or in cars.


The block weighs 14.8 lbs. The engine Powel Crosley is holding weighed 58 lbs. Complete with all accessories including flywheel it still only weights133 lbs.

The early CoBra engines had straight cut gears on the tower shaft/cam. Later engines went to the spiral cut gears to quiet down the valve train a little. Because of the thin sheet metal construction the noise level of a tin engine is still high, almost sounding like a diesel.

Early CoBra (wrong color)


The installed Mooney-Crosley, the propeller is driven off the flywheel end of the crank, so it is mounted facing back.  It was modified by the Crosley factory for the application.  The first 12 aircrafts were delivered in 1948 powered by CoBra but were later recalled and upgraded to Lycoming 65 hp engines because of a crankshaft problem and anticipated problems. More Mooney details can be gotten from Mooney History, Production, and Specification

One of the surviving engine is on display at the Kansas Aero Museum at McConnell AFB in Wichita.

The distributor has eight leads coming out.  The rotor has two fingers that point 180 degrees from each other so that when the coil fires, two of the leads get the voltage.  One wire goes to the right side and the other to the left side.  Two spark plugs in each cylinder. Light weight welded up exhaust manifold is used. Propeller driven by 3 belts.

CoBra Engine Serial Numbers

6/46 to 12/46

CC46-100 to CC46-5586

1/47 to 9/24/47

CE7-5587 to CE7-21999

9/24/47 to 12/47

22000 to 28803

1/48 to 1/49

28804 to 62725

The engine number is to the rear of the distributor on the crankcase.

Many/most CoBra engine have been converted to cast iron blocks, checking the engine serial number is a good way to see if your engine started life as a CoBra.  You may also find an "R" on the serial number boss, it appears this was a stamp put on by the factory if they rebuilt the engine either as another tin block or converting to cast iron. You can see by the numbers there was over 62,000 CoBra engines made.  Best guess on true Crosley embossed cast iron engines is about 45,000.

Mystery CoBra

Here is a CoBra that has two serial numbers.  The R indicates a probable factory rebuild but why the new serial number.

Mooney   Peak


Peek Wildcat Boat motors were built in at least 1949. 80 hp out of 88 CI in the Sr. engine, the regular Peek Wildcat had a stroker crank and boosted the Crosley 44 CI engine to 48 CI for the 48 class in boat racing. Available in both cast iron and tin versions. Note the picture above shows a mirrored CoBra block.  Also heard rumors of a straight 8 Peek. Peek 45 Ad

Jack Van Deman wrote: My father Jack Van Deman, and Grandfather J. N. Van Deman had the first and second Peek Wildcat 88.  My grandfather had purchased a 9 ft. inboard named "Shorty" powered by a tin block Crosley from Peek in 47 or 48.  Peek raced it against 135 Cu In Hydros.  My family then went on to get the 48 cubic in hydro class established with the APBA. Peek contacted my grandfather and told him he could build a 91 cu in hydro that he would guarantee would set a record.  The boat designed by Peek and the engine a twin block Crosley run through a gearbox with a single output shaft was first run in Salten Sea and ran over the mile straight away record one way.  It was delivered to my grandfather in St. Petersburg, FL in Feb 1949.  The boat went on to win the race for the 91 class and won three consecutive Nationals and was never defeated when it finished both heats of racing.  My father set a world record with the boat in 1951 of 59.960 MPH.

Shorty with 45ci Peek Engine

The end of the Mighty Tin - The parts manual lists Engine # 62725 as the last Tin Block.

A factory letter was sent to all Crosley dealers on Feb. 3, 1949. It stated that starting on January 24, 1949, all cars would incorporated the new Crosley CIBA (Cast Iron Block) Engine. "All cars shipped since January 24 have had a sticker applied to the inside of the windshield. When it is removed, the external appearance of the car is, of course, the same as that of any other car. It will take several weeks before we make a public announcement of this change, but we are passing this information on to you in advance and in confidence for your own information and protection."

CIBA Years

Correction or additions are welcome.
Taylor Years CoBra Years
CIBA Years
Post Crosley Big Block Years

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