Steering Servo: How much torque is enough?
 

Hey fellas!
So I saw this video the other day where a guy has this jig set up with a scale and an amp meter and he tests several servos to see if they meet the advertised specs. One of the servos he tested pulled 559.5 oz-in at 5.7 volts but it drew 7.28 amps! It got me thinking though how much is too much, 559 seems like way overkill. And most ESCs only have a 2amp or so BEC built in. So I guess what I was thinking is how much torque do you really need for the various applications? Maybe some of you with more knowledge and experience than me could chime in with your opinions. For example how much torque for a 4wd short course truck or a touring car or a rock crawler. I think it would be nice just to get the information out on a thread so down the road if someone tries doing a Google search (like I did before posting this thread) they will be able to have a good reference. Cause servos are expensive. Thanks guys.

Here's the video of anybody wanted to watch it. It's pretty interesting

In order from most to least torque
rock crawling = the more the better at least 250 oz/in, speed doesn't matter than much as long as its below 0.20 sec
1/8 buggy/truggy = eh try to stay above 220 oz/in on steering, 150 on throttle, speed try to keep it under 0.15 sec
1/10 short course 4wd = 200+, under 0.15
1/10 buggy 4wd and sc 2wd and 1/10 stadium and 1/8 and 1/10 nitro onroad= 150+, under 0.10
1/10 buggy 2wd = 100+, under 0.10
1/10 tc onroad = 100+, fast as possible ex: 0.055

I probably left some categories out, just approx and personal judgement, in general for racing, the faster the better.
The servos that I think are good options
1258tg for any 1/10 offroad class $70 166 ozin, 0.08 sec
1257tg if you want a faster servo for 2wd buggy basically different gearing of the 1258
Team powers dcs/sgs for andy 1/10 class offroad or onroad. This is my favorite servo with 220 ish oz in of torque, its shorty so it saves space and fits in onroad and its 0.055 sec speed is op. Its a little price at somewhere around $120ish
In general savox is a safe bet on a budget, team powers is great, protek and mks not much experience but heard good things, traxxas is bad, any plastic gear is bad unless your on a really tight budget.

Perfect this is exactly what I was looking for. Thanks man. Also I second the comment on Traxxas servos. They don't center for crap and always seem weaker in one direction.

Does dynamic torque make that much of a difference when it comes to servos? I can't imagine it would effect the rating all that much but I'm probably wrong. You would know more about it than me.

Those are made by AGG and the same as the A80BHSW in case anyone is interested.

Yep. One thing to note is Send It claims to have a 120 day warranty while AGF is 1 year.

If you need 458 oz of torque for your throttle I would suggest trying a drop or two of oil on the throttle assembly :smile:

For crawling its nice to have the extra torque. But for any racing, something is definitely up. Maybe spilled entire ca bottle onto the steering rack?:weird: