More 56 questions

[Edward M.]

OK, I finally located the Chevrolet Bulletin dated April 6, 1956 that announced RPO 469 as the optional two four barrel engine, and made the single four barrel engine the base motor.

I have come across something else that is puzzling. The Automobile Manufacturers Association Consolidated Specification Questionaire, Issued 1-6-56, Revised 7-9-56 has the following information:

Drive Unit - Convential Transmission
Transmission Ratios:
1st gear: 2.94:1 @
2nd gear: 1.68:1 @
3rd gear: Direct @
Reverse: 2.94:1 @

@ Optional transmission: First 2.2, Second 1.31, third direct drive, reverse 2.2

Does anyone know anything about this optional transimssion? I never realized this info was there before.

[Scott S.]

Re: More 56 questions

Ed, All 1956 Corvettes came with he Close ratio 2.20 first gear. Most will do 65 mph in second.
Scott

[Gary C.]

Re: More 56 questions

Ed, please refer to the "1955-62 Corvette Three Speed Transmission Spelled Performance" Restorer article by Paul Henricksen & Stan Edmunds. The gear ratios you've listed are the Corvette close-ratio gears. There were no optional gears for 56-7 Corvettes, just the close-ratio gears according to Paul & Stan. Gary....

[Mike M.]

Re: More 56 questions

2.94:1 is almost certainly the standard or base pass car first gear ratio. don't believe these wide ration 3 speeds saw any c-1 vette application, just most pass cars. my 57 250HP 210 sedan's original 3 speed is a close ratio tranny but its an exception for pass cars in the shoebox era.mike

[Edward M.]

Re: More 56 questions

Do we know this ALL 56 Corvettes had this 2.20 ratio transmission, even the single four barrel cars? I am still wondering about the AMA document.

[John H.]

Re: More 56 questions

Ed -

Colvin's CBTN agrees - it calls out the close-ratio gearing for '55-'60 Saginaw 3-speeds (2.20, 1.31, 1.00, R2.20).

[Edward M.]

Re: More 56 questions

OK, I'm convinced. Thanks.