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Qube
01-06-2007, 10:59 PM
So I'm reading about this ugly phenomenon. Apparently it is most prominant in FWD cars at standstill. Supposedly due to flexing in uneven halfshaft lengths. Can anyone clarify this further, fact from fiction?

ericcamaro
01-06-2007, 11:16 PM
we had this problem come up on a 65 stang we were building. Too much power made the engine torque over and it felt like the whole front end lifted up the power pretty much takes over and there is no steering till you take your foot out of it. very scary.

hk20000
01-06-2007, 11:31 PM
I don't think that's the common understanding of torque steer....like at all.

Torque steer is limited to FF / 4WD cars with power(of course torque, too) sent to the front wheels.

the 2 wheels basically struggle for grip because the LSD or the open diff is acting differently on 2 wheels and send the steering wheel steered to one direction against the driver's will.

for more information visit wikipedia.

Qube
01-06-2007, 11:41 PM
I don't think that's the common understanding of torque steer....like at all.

Torque steer is limited to FF / 4WD cars with power(of course torque, too) sent to the front wheels.

the 2 wheels basically struggle for grip because the LSD or the open diff is acting differently on 2 wheels and send the steering wheel steered to one direction against the driver's will.

for more information visit wikipedia.

See, that's why I am confused. The wikipedia entry seems one dimensional and not jive with what you're saying... unless I'm reading it wrong.


Torque steer is mainly caused by unequal length half shafts between the transaxle and wheels. When excessive torque is applied, the longer half shaft flexes more than the shorter one, thus causing one wheel to momentarily spin more slowly than the other, resulting in a steering effect. Ford engineered a simple method of reducing torque steer on its front wheel drive cars by expanding the transaxle to equalize the lengths of the half shafts.

Paul in NZ
01-06-2007, 11:59 PM
A freind of mine had a fwd turbo that had visciuos tourque steer.The first time you would floor it(as an individual) the reaction would take you by surprise and you would use two lanes,swerving from one to side of the road to the other.First one wheel would spin suffering a rela tive lack of traction.then the other...once you got used to it it was more controllable

repenttokyo
01-07-2007, 12:02 AM
I don't think that's the common understanding of torque steer....like at all.

Torque steer is limited to FF / 4WD cars with power(of course torque, too) sent to the front wheels.

the 2 wheels basically struggle for grip because the LSD or the open diff is acting differently on 2 wheels and send the steering wheel steered to one direction against the driver's will.

for more information visit wikipedia.


this is exactly what torque steer is. It can be aggravated by things like uneven length half shafts

///Sniper535
01-07-2007, 12:17 AM
From experience, FF cars has noticable torque steer, the VW's GTi has it bad at times, and a Ford Freestar we use for work also has a jerky torque steer.

winfred
01-07-2007, 12:22 AM
it's fun in something with power high pressure volvo 850 turbos can be nasty, a good part of the problem comes from traction differences from one side to the other, the one that slips lags behind and can make it feel like the car wants to jump in the nearest ditch, another fun point is understeer because you are just asking too much from the contact patch both direction control and thrust, the car is then jumping towards the afore mentioned ditch and you lift transferring weight and traction back to the front end, then the assend wants it's turn at steering, front wheel drive sucks!

Anton CH.
01-07-2007, 05:09 AM
Check out some Acuras, some of them put the engine like in a RWD configuration to fix this.

RallyD
01-07-2007, 02:48 PM
So I'm reading about this ugly phenomenon. Apparently it is most prominant in FWD cars at standstill. Supposedly due to flexing in uneven halfshaft lengths. Can anyone clarify this further, fact from fiction?

it is from unequal shafts. It can be corrected somewhat by increasing the diameter of the longer shaft. Manufacturers have tried to fix this by 1. using equal length shafts, or 2. making a 2 piece halfshaft that gives equal length between the CV joints.

My PT has an aftermarket turbo and unequal shafts, it exibits more torque steer than the PTGT with getrag trans and equal length shafts. The Saab 900T was the one vehicle I drove that nearly ripped the steering wheel from my hands. Omni GLH was another. It is a FWD problem.

If you have torque steer in a RWD then the torque angle (axle vs. center of vehicle) is not 90*