> In Neb. tests, every gear is tried until "maximum pull" is attained . .
There are multiple facets to the standard Nebraska tests, not all of them
test maximum pull. And, as I said before, maximum pull is _not_ maximum
horsepower.
The test _you_ quoted (note the underscores are standard lingo for
emphasis), said "loaded to rated horsepower".
> I'll explain the test procedure: the 25% miraculous gain in test G dbhp
> was achieved by the allowance of unlimited cast iron and/or liquid
> tire-fill
> weight. . . in some cases, tractor are loaded with ballast weights
> approaching the weight of the tractor itself; not practical for daily use
> and really tough on the tractor.
>
> Randall figures I made that up!
No, I didn't "figure you made that up", but note that Nebraska law states
"Additional ballast may be added to the tractor as specified by the
manufacturer." and "No modifications that would void the warranty are
allowed." It's up to the manufacturer's representative how much weight (if
any) is actually added. I wasn't there, I don't know how much they added,
and the tests results you quoted didn't specify either. If you have more
actual facts, feel free to share them with us.
However, I found a site that says for test #575 in 1956 they added 700
pounds. Certainly not "approaching the weight of the tractor itself".
> Sorry you haven't grasped this but adding weight added 25% to the drawbar
> horspower in this particular test G. Drawbar horsepower IS the numerical
> expression, the measurement of tractive effort with travel speed a factor.
It's tractive effort TIMES speed. Double the speed, get half the tractive
effort, the drawbar horsepower is unchanged. Kinda like the relation
between engine horsepower and torque, they are related, but not the same
thing, and peak power does not occur at peak torque. Adding weight does not
add horsepower, otherwise you'd be seeing weights on race cars <g>
My car delivers a fairly honest 100 "drawbar" horsepower at 90 mph, but
there's no way it could deliver 1600 lbs of pull (if for no other reason
than it has less than 1000 lbs over the drive wheels).
> It is clearly stated in the test:
> It delivered 8.75 hp in first with weights, that's it's maximum with
> weights.
> It delivered 6.75 hp in second without weights, that's it's
> maximum without
> weights.
Nope. Even accepting your assertion that the first test was for maximum
pull, not rated horsepower as stated, maximum pull is not the same thing as
maximum horsepower. The second test was also for maximum pull.
> The "Google" search engine found 1780 references to "Nebraska tractor
> Tests". Check it out if you'd like to learn more of the official United
> States standardized tractor tests.
Excuse me, the Nebraska tests are the official ... Nebraska tests. Got
nothing to do with official United States tests ...
Randall
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