Can B transmission ratios be changed?

This may be a dummy question but do other model tractor gears interchange with a B transmission? Say I wanted to change my third gear to a lower ratio giving me more ground speed, would CA or WC gears interchange? Or how about a splitter/ overdrive like a Sherman in Fords? I suppose I could do mods engine wise to increase usable unloaded RPM and it would not be obvious, I plan on increased compression, static balancing, hardened seats and Torrington cam thrust bumper anyhow so I could get away with 2000 RPM maybe? I am also looking at taller tires to gain some ground speed. Just been mulling over possibilities is all.

This was in a C.

I do not want to kill the original look of the tractor, optional accessories like a Sherman would be cool. Rated RPM is 1400 so with my calculations that would give me about 8 MPH. The tractor cruise definition as acceptable speed is 10 MPH cruse speed so I am quite short of that. I did a dual trans on my Power King tractor and made the second trans an overdrive as it came with an optional rear diff that made the thing go about 4 MPH at full throttle. Yes it gets unstable at 35 MPH but I never go that fast with it. We have a few Fords and JDs that will do 20 easy ( one with an over under Sherman) and if the front end is tight with good tires and alignment they drive fine. I am thinking of using the tallest AG tire I can which is the Carlisle HA 45 11/24 and increasing engine RPM will get me to 10 MPH without beating the engine to death. Everything is going to be new and modernized in the engine and drivetrain completely rebuilt with Timkin -2 grade bearings so I should be OK there. The engine will be static balanced and hardened seats installed along with a Torrington roller cam thrust bumper. I am also going with 5/16 Cromolly push rods. The lifter bores I am thinking of installing guides in also to tighten things up and increase valve train stability. The engine has immense wear and the crank was shot so I am starting from scratch with everything anyhow. I am planning on using the tractor mainly for cruises and show unless I can find a 1 bottom 16" trip plow, which are impossible to find. I have a two bottom 14" trip JD but the B will never pull that, the B JD was a much heavier and more HP. The oil pump was also hosed so that will need to be replaced as one of the vane springs broke and ate the end plate up, once I get a more acceptable core then I with rebuild and blue print that along with a slightly higher rate relief spring to increase pressure from 19 PSI to 30. I thought maybe if the carrier, ring and pinnion or gears could be swapped I could take some strain off of the engine but I do not want to destroy the original external appearance of the tractor. The front axle I am having the spindles welded and turned, beam milled and bored true then sintered bronze bushings made to correct the nasty wear on the front end. The pivots I already installed new square head grade 5 bolts and I have bushed every pivot on the tractor including the clutch pedal and governer. So slop will not be an issue just getting run over by a Farmall might be an issue LOL.

Of course that is full governed throttle, I would not want to run for hours at full throttle either. I am not sure how fast I would want to spin the engine for long durations? Bursts of 2500 would not grenaded it I am sure but I guess I will have to look more into what internally I can do to the engine to make it more RPM friendly. I just did my nephews Model A with a Scatt crank and that of course added counter weights to the crank like a modern engine, something not possible with the B engine so I am limited as to what I can do I guess.

DrAllis wrote: If 1400 RPM yields 8 MPH now, 1750 RPM gets you 10 MPH....2200 RPM gets you 12.5 MPH.

Still aint gonna keep you ahead of the Farmall.

I tip my hat to IH. They knew the meaning of road gear.

Nathan (SD) wrote: DrAllis wrote: If 1400 RPM yields 8 MPH now, 1750 RPM gets you 10 MPH....2200 RPM gets you 12.5 MPH. Still aint gonna keep you ahead of the Farmall. I tip my hat to IH. They knew the meaning of road gear.

If high gear is direct drive, there would be no gears to swap anyhow.   Unless you change the ring and pinion or the final drives. But either would change every gear's speed.

irlbeck A-C'S wrote: This was in a C.

Bet they are rare too $ CA- CHING!

Sounds like the easiest route is either a CA transmission or go for the high crop bigger rear tires.

The B and C transmissions in 3rd gear are in over-drive and not 1 to 1. Top shaft input gear has 27 teeth driving a 22 tooth gear on the bottom.

CA-D10-12-14-15 all drive from the top shaft with 49 teeth to a 24 tooth on the bottom shaft in road gear.

"Top shaft input gear has 27 teeth driving a 22 tooth gear on the bottom."

That information, coupled with the exact center distance between shafts could help with new gears for a different ratio. Next thing to check would be if there is room for a larger upper gear.

I'm not sure they would bolt up , but if they would you would eliminate the bull gear reduction .