1LikesInferno MP9 thread
10-10-2016, 02:30 PM - Wikipost
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03-04-2015, 07:28 PM
That's pretty much how I've always understood torque steer to occur. But the original post mentioning torque steer was in reply to my comment about my car getting crossed up when slowing from high speeds. How can torque steer even occur when decelerating, as there isn't any torque being applied to the wheels when braking. Is it possible for torque steer to occur while braking?
I use the ABS function on my radio, also with a delay set so it doesn't kick in instantly. And as mentioned above, brakes are not an on/off switch, just like throttle is progressive and one doesn't need to pull the trigger to WOT every time they accelerate, same goes for braking.
An interesting discussion though.
I use the ABS function on my radio, also with a delay set so it doesn't kick in instantly. And as mentioned above, brakes are not an on/off switch, just like throttle is progressive and one doesn't need to pull the trigger to WOT every time they accelerate, same goes for braking.
An interesting discussion though.
From this http://en.wikipedia.org/wiki/Torque_steering
Asymmetric driveshaft angles due to any combination of
Unequal driveshaft length or diameter
Torque steering effect simulated using MSC Adams.
Transient movement of the engine
Tolerances in engine mounts
Body roll
Single wheel bump
Different driveshaft torques left to right (due to wheel bearing or differential problems)
Suspension geometry tolerances
Unequal traction forces due to road surface (µ-Split) in combination with kingpin offset
03-04-2015, 09:38 PM
Tech Initiate
The torque steer was just an idea. But from this discussion it seems the car crossing up under high speed hard breaking isn't torque steer. I thought about it and it seems that what is causing the car to cross up under breaking is the outside wheels wanting to spin backwards and the inside wheels spinning forward. Which I think is caused from the difs unloading.
03-05-2015, 01:20 AM
Tech Master
iTrader: (16)
The torque steer was just an idea. But from this discussion it seems the car crossing up under high speed hard breaking isn't torque steer. I thought about it and it seems that what is causing the car to cross up under breaking is the outside wheels wanting to spin backwards and the inside wheels spinning forward. Which I think is caused from the difs unloading.
I've never really understood what the phrase "diff unloads/unloading" means. Hear and read about it everywhere but what part or component of the diff is actually being unloaded? Does it refer to having the torque from the engine removed and the diff being in a freewheeling situation? What is the consequence of a diff unloading and is there anything can be done to reduce or stop this from occurring somehow? Is there anything you can suggest to alleviate this issue? When it happens, the car always gets crossed up to the right and having to countersteer to the left with the radio - does this give any indication for what to do because it always happens the same way? I kinda thought it might be coz of the extra and offset weight of the engine and fuel tank maybe? But then I've never seen it happen to Tebo or King and at the WC which King won in Pattaya, that track had huge speeds along front straightaway and quite a slow corner at the end. And, when I think about it, never happens to them on any track which I've watched their races online but, quite obviously, I sure can't drive anything like them. Maybe it is because the wheels are locking up just a little and I should back off the EPA slightly or perhaps just always use the ABS function on my radio?
Any input is appreciated. Cheers.
03-05-2015, 01:42 AM
I've never had that happen with my MP9. However I was driving my e-truggy (ST-RR EVO) in front of my house the other day with really bald tires. It was stopping straight. Then I decided to crank up the brake EPA to see if I could get it to stop sooner and faster since the street had a lot of grip. Immediately it stayed doing the torque steer braking thing when I went to full brake. All I can conclude is the power of brakes of the motor transferred a lot of weight to the front (street really grippy so front tires dug in) which unweighted the rear tires, locking them up and causing them to skid to the side. Still not completely sure why they wouldn't skid straight. If you were driving a full size car and yanked the e brake would it stop straight or fish tail the rear?
03-05-2015, 05:19 AM
Tech Master
Sollution involves thicker diff oils.
03-05-2015, 09:03 AM
In thinking of this in simpler terms, what I guess to be happening is that the good amount of flex built into the chassis is allowing it to twist under stronger braking on a rolling axis and making the car weave to the right. If the epa is set really high on cars with full plastic radio trays, you can see the whole tray twist along the roll axis. My .02 cents.
03-05-2015, 11:14 AM
^^ Spads11, how do you like the MP9E? Im on the fence, I know it should be a no brainer....
03-05-2015, 03:01 PM
03-05-2015, 04:12 PM
Tech Regular
iTrader: (4)
Does anyone have any experience using the ready set unmilled chassis on there spec A? I was wondering about flex and what grade of aluminum???
03-05-2015, 04:26 PM
You should come out on WXE David 
03-05-2015, 05:19 PM
Yes, most full-sized cars will not stop straight if all 4 tires are locked up. The rear end always starts to come around if the skidding last long enough. I've always assumed it was because of inertia.
All the weight behind the locked up front wheels will still be wanting to move forward more rapidly than the front wheels, that get much more traction because of weight bias at that point, will allow. So, when the rear wheels lock up too, and since they don't have as much weight on them, the inertia will cause them and all that weight to try and go around, or to the side of the front wheels, thus skidding sideways.
I'm no engineer, and I may be way off base, but this is how I have always thought of it.
Whenever my buggy is crossing up under heavy braking, I always just take out some rear brake so the rear tires don't lock up, and the problem goes away. Because if the tires stay turning, they will always track better than if they are completely stopped. That's why people that drive in the snow alot always pump the brakes when trying to turn and slow down at the same time, a locked up tire in the front won't steer, and locked up rear tire won't follow.
Yanking the ebrake will DEFINITELY cause the car to fishtail...lol, I know that from fun experiences.
Just my thoughts...feel free to tell me I'm crazy.
All the weight behind the locked up front wheels will still be wanting to move forward more rapidly than the front wheels, that get much more traction because of weight bias at that point, will allow. So, when the rear wheels lock up too, and since they don't have as much weight on them, the inertia will cause them and all that weight to try and go around, or to the side of the front wheels, thus skidding sideways.
I'm no engineer, and I may be way off base, but this is how I have always thought of it.
Whenever my buggy is crossing up under heavy braking, I always just take out some rear brake so the rear tires don't lock up, and the problem goes away. Because if the tires stay turning, they will always track better than if they are completely stopped. That's why people that drive in the snow alot always pump the brakes when trying to turn and slow down at the same time, a locked up tire in the front won't steer, and locked up rear tire won't follow.
Yanking the ebrake will DEFINITELY cause the car to fishtail...lol, I know that from fun experiences.
Just my thoughts...feel free to tell me I'm crazy.
Last edited by WYLDTHING; 03-05-2015 at 06:32 PM.
03-05-2015, 05:34 PM
who needs brakes anyway ? 
besides "THE JQ" anyway
besides "THE JQ" anyway
03-05-2015, 05:34 PM
03-05-2015, 05:44 PM
03-05-2015, 06:30 PM
Yes, most full-sized cars will not stop straight if all 4 tires are locked up. The rear end always starts to come around if the skidding last long enough. I've always assumed it was because of inertia.
All the weight behind the locked up front wheels will still be wanting to move forward more rapidly than the front wheels, that get much more traction because of weight bias at that point, will allow. So, when the rear wheels lock up too, and since they don't have as much weight on them, the inertia will cause them and all that weight to try and go around, or to the side of the front wheels, thus skidding sideways.
I'm no engineer, and I may be way off base, but this is how I have always thought of it.
Whenever my buggy is crossing up under heavy braking, I always just take out some rear brake so the rear tires don't lock up, and the problem goes away. Because if the tires stay turning, they will always track better then if they are completely stopped. That's why people that drive in the snow alot always pump the brakes when trying to turn and slow down at the same time, a locked up tire in the front won't steer, and locked up rear tire won't follow.
Yanking the ebrake will DEFINITELY cause the car to fishtail...lol, I know that from fun experiences.
Just my thoughts...feel free to tell me I'm crazy.
All the weight behind the locked up front wheels will still be wanting to move forward more rapidly than the front wheels, that get much more traction because of weight bias at that point, will allow. So, when the rear wheels lock up too, and since they don't have as much weight on them, the inertia will cause them and all that weight to try and go around, or to the side of the front wheels, thus skidding sideways.
I'm no engineer, and I may be way off base, but this is how I have always thought of it.
Whenever my buggy is crossing up under heavy braking, I always just take out some rear brake so the rear tires don't lock up, and the problem goes away. Because if the tires stay turning, they will always track better then if they are completely stopped. That's why people that drive in the snow alot always pump the brakes when trying to turn and slow down at the same time, a locked up tire in the front won't steer, and locked up rear tire won't follow.
Yanking the ebrake will DEFINITELY cause the car to fishtail...lol, I know that from fun experiences.
Just my thoughts...feel free to tell me I'm crazy.
Think your on to something. Recently looking at brake upgrades for my road car, almost all of them have oversized front brakes and tiny rears rotors/callipers. Never really noticed until I was in the market to buy upgrades hehe.
