190XT Tach With groundspeed
Printed From: Unofficial Allis
Category: Allis Chalmers
Forum Name: Farm Equipment
Forum Description: everything about Allis-Chalmers farm equipment
URL: https://www.allischalmers.com/forum/forum_posts.asp?TID=209564
Printed Date: 02 Jan 2026 at 2:05pm
Software Version: Web Wiz Forums 11.10 - http://www.webwizforums.com
Topic: 190XT Tach With groundspeed
Posted By: MadCow
Subject: 190XT Tach With groundspeed
Date Posted: 01 Jan 2026 at 7:14pm
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I really like having all the lines on the tachometer with ground speed based on gear. The D21 and D19 tachometers spin the same direction as the 190, and have these marks. Any idea which would have the closest gear ratios? I don't have a parts/service for either D series to compare transmission specs. 190xt Gear main counter ratio 1st 36T 13T 0.36 2nd 31T 18T 0.58 3rd 27T 23T 0.85 4th 19T 35T 1.84 Differential 9 to 35 or 3.88 Final drive 13 to 93 or 7.15 I can't figure out the ppower director but I think: Gear drive driven ratio Low 27 30 1.11 High 19 26 1.37 'gear' total ratio 1 11.09 2 13.68 3 17.86 4 22.04 5 26.17 6 32.30 7 56.66 8 69.93 Hmmm. Math isn't adding up. I'm missing something somewhere. But this can start a conversation. |
Replies:
Posted By: rw
Date Posted: 01 Jan 2026 at 7:32pm
| I use an old radar planter monitor that has ground speed spray, also the light bar I use has MPH. Both are old technology now, not real expensive, tire size and slippage are moot. The old Tachs with mph are cool and get you close. I find the more modern tools more accurate for mph especially spraying. |
Posted By: Les Kerf
Date Posted: 01 Jan 2026 at 7:42pm
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rw wrote:Posted By: MadCow
Date Posted: 01 Jan 2026 at 8:07pm
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It's not the novelty than precision, really, for me. I think old simple mechanical tech is better than electronics, and I like the sleak look. It might be futile, because I might get a spray controller and radar anyway... But dang I like the look of the full tachs, and the simplicity. |