[AT] Greg E, Gene D or anybody - VAC HP bump-up question.

[Ken Knierim]

Farmer,
I can't find my copy of "Full Steam Ahead" but I recall a note in there
about how Clausen (the fella running Case at the time) forced the engineers
to turn the RPM down on the VA series because its power overlapped the S
series (might have been the Continental engine from the V's; it's been
awhile since I read it). He wanted to sell the bigger tractors since there
was more profit in them. Apparently the same mentality kept the engineers
from making the VA series with a 6-speed configuration when the price was
under a couple bucks to add the gears. I believe they used Clark
transmissions (or at least parts) for the gearboxes. More revs, more gears
and the VA would have been a lot more tractor.

I would guess the governor is the only difference. I haven't heard anyone
mention a different camshaft for this little engine unless you go to the
aftermarket. It's probably capable; it's not like this is a really long
stroked engine like its bigger brothers. Gotta get air through it so more
revs are about the only easy way (if PTO speed isn't an issue).

Ken in AZ


On Wed, Jan 13, 2010 at 7:47 AM, Indiana Robinson
<robinson46176 at gmail.com>wrote:

> Are the VAC and VAI engine the same except for the governor setting?
> Did Case bump up the RPM on the VAI for more HP (tractor makers have
> been doing that about forever) or did they think that the VAI would
> be driven more car or truck like rather than running full throttle out
> in a field all day for days on end? Maybe they wanted more ground
> speed?
> The info I have is:
> All agricultural tractors
>                                      No load speed 1600 RPM
>                                      Full load speed 1425 RPM
> VAI Tractor (Industrial)
>                                      No load speed 1925 RPM
>                                      Full load speed 1800 RPM
>               *1425 RPM for proper PTO speed
> Did Case ever use the VAC engine in anything else like a later tractor
> at the higher RPM (like maybe the 300 etc.)?
> My Deere 4020 has a throttle made so that you have a stop at regular
> full speed for normal work and then you pull out on the knob and pull
> it down farther for tough spots or for road use. I think the top speed
> is something like 2500 RPM and the regular setting about 2200 RPM.
> For years I had a tiny cable on my Farmall CUB so that when mowing I
> could pull gently on the cable just as I approached a big clump of
> really tough stuff and get a jump on the rather slow to react
> governor. Once out of the tough patch I would let it drop back to the
> regular full speed. I'm not using it to mow with right now but I
> finally changed the throttle/governor settings so that I had a paint
> mark on about the third notch back and I mowed there 95% of the time
> but could shove it forward 3 notches just in the tough spots (I just
> copied the idea from the 4020).
> I just looked out of curiosity and the Continental on my Ferguson
> TO-20 calls for a no load maximum RPM of 2200 and a loaded RPM of
> 2000.
> Going back over many years the tractor makers have always made a big
> deal about not increasing governor speed settings then a few years
> later when they wanted a little boost the only change they would
> sometimes make was a 200 RPM boost in the high speed setting.
>
> --
> Have you hugged your horses today?
>
> Francis Robinson
> aka "farmer"
> Central Indiana USA
> robinson46176 at gmail.com
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