Finally got a running 65 C10

[DoubleDingo]

I don't understand this logic? They were used in cars like Impalas with highway gears that were probably heavier than short, 2wd C10's. How would it be any different than taking off in 1st with the stock 3 speed, or 2nd (1st after granny gear) in the 420?

There were also different ratios used in the Saginaw 4-speed. They can be identified by the number of grooves on the input shaft.

With the sm420 you're using 2nd gear as 1st for 99.99% of all takeoffs.

The Saginaw 4 speeds, and 3 speeds do have desirable 1st gear options, but I have never seen any other than the zero groove 2.84 1st gear. That 1st gear ratio, even with 4.57 rear end ratio is a pain upon take off sometimes.

Every vehicle that came with the 3 speed or 4 speed from the factory, all had engine torque, tire size and axle ratio accounted for.

With minimal to almost zero Saginaw 1 groove(2.54), 2 groove(3.11) or 3 groove(3.50) 3-4 speed 1st gear transmissions out there, that leaves the 0 groove with 2.85 1st gear transmission, and it's not nearly as good as the sm420 with its 3.60 2nd gear used as 1st gear.

 

[bucket]

With the sm420 you're using 2nd gear as 1st for 99.99% of all takeoffs.

The Saginaw 4 speeds, and 3 speeds do have desirable 1st gear options, but I have never seen any other than the zero groove 2.84 1st gear. That 1st gear ratio, even with 4.57 rear end ratio is a pain upon take off sometimes.

Every vehicle that came with the 3 speed or 4 speed from the factory, all had engine torque, tire size and axle ratio accounted for.

With minimal to almost zero Saginaw 1 groove(2.54), 2 groove(3.11) or 3 groove(3.50) 3-4 speed 1st gear transmissions out there, that leaves the 0 groove with 2.85 1st gear transmission, and it's not nearly as good as the sm420 with its 3.60 2nd gear used as 1st gear.

I didn't realize that 2nd gear was that steep. However, that is a large rpm drop between gears, compared to a traditional 4 speed. A traditional car type 4 speed can also be shifted in a much more spirited manor.

 

[DoubleDingo]

I didn't realize that 2nd gear was that steep. However, that is a large rpm drop between gears, compared to a traditional 4 speed. A traditional car type 4 speed can also be shifted in a much more spirited manor.

I guess I never knew any better, as I shifted my sm420 just fine in many different types conditions and scenarios, that I never knew the difference between the Saginaw 4 speed in the 56, or the sm420 in Mean Green. I was much younger and dumber back then, and also drove a wide array of vehicles with varying granny-geared 4 speeds, automatics, column shift, etc. If I could do it all over again give me a 350/sm420/3.54

 

[idahovette]

All I gotta say Shane @DoubleDingo is you gotta be a MAGICIAN if you can shift a 420 like you can an M20 or a Saginaw!!!!!!!