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Discussion Starter · #1 ·
A friend of mine who is a mechanic meantioned something to me the other day i thought was intersting. thought i'd run it by you guys.

The reason our cars have such bad torque steer is because the transimission isn't exactly in the middle of the car. There is something, a "transverse axle" (that might be what its called) and this makes the axles on a non-center aligned transmission car the same length. SAAB doesn't do this, and the result is that the right axle is longer than the left. This causes one side to have more power than the other, a difference in traction, and then torque steer.

Apparently we can have custom driveshafts made to conteract this, but it sounds like an expensive process, one not to be undertaken unless running an insane amount of HP. Does anyone have any experience with this, i appologize if i use a wrong term or two, but maybe someone knows the right ones.
 

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LOL your friend needs to take a good hard look under your saab and then he will feal very silly :roll: all saab transverse engines have the left hand shaft the same length as the right hand, there is an intermediate shaft coming out of the gearbox to the RH front wheel and then bolted to the back of the engine is the inner C/V cup with the shaft coming from there to the wheel
 

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I am going to go out a non-technical limb here but since the Steering Rack Brace eliminated 100% of my torque steer could an alternative theory be that the steering rack is too flimsy and flexes under the force of hard acceleration?

Of course, then I would have account for the unbalanced power to something like varying friction from the tire to pavement (complete guess)? Am I correct in saying any torque steer I ever experienced wasn't consistent to one side or the other? Thus the riding the bull feeling (gotta say I miss that a little).
 

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Discussion Starter · #4 · (Edited)
I don't really think you can loose 100% of your torque steer from the steering rack brace alone. Our cars are front wheel drive and develop a good amount of torque off the line. The brace mainly stops the steering wheel from jumping around when you accelerate/burnout.

What about larger rims with low profile tires. Don't they grant you more traction since the rim is wider at the base and a thinner tire is closer to this wider base. My understanding is that Cross-cut-surface area is really the most important thing for sticking to the road.I understand the effects of riding with thinner tires, but im wondering if it'd be worthwhile in the interest of traction.
 

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Sorry, there goes the optomistic rounding again.

The Steering Rack Brace reduced my* torque steer to an un-noticeable level.

* lowest HP range of members here
 

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Would that be; Brake HP, Wheel HP; HP at flywheel; Perceived HP; Dreamed-up HP or plain old Bul~~it HP? :suprised;

Riding the Bull. I Like it!:cheesy: :cheesy: :cheesy: Yeehaaa! Whoaa there!

(Hp 350. Oh, no hang on, forecast says hi pressure, that'll make it 360 then).
 

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Castro_9 said:
could an alternative theory be that the steering rack is too flimsy and flexes under the force of hard acceleration?
That's the biggest part of it. Most front wheel drive cars that successfully keep torque steer to a minimum have the steering rack mounted low and bolted to something very stiff, like the frame. Why this platform has it bolted high up and on the firewall is beyond me. I'm assuming it's in the same place on the Vauxhall Cavelier, and that this wasn't a Saab screw-up, but I could be wrong.
 

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Safety probably?!? Our cars have a steering rack that will break in a major front end collision....instead of the kind that do NOT break and enter the cabin of the car, impaling the driver.
I'll deal with torque steer (which I do not experience much) for the safety...if that's it.
 

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Jeremy R. said:
Why this platform has it bolted high up and on the firewall is beyond me. I'm assuming it's in the same place on the Vauxhall Cavelier, and that this wasn't a Saab screw-up, but I could be wrong.
You're quite correct; though the torque steer is not an issue with the fwd Cavalier/Calibra because the max power available was 157bhp with N/A 2.0 or 170bhp with the 2.5V6 both with power delivery at the peak end of revs, not causing major torque steer: the turbo Cav/calibras all had 4wd so the torque dump went to all 4 points via an electronically controlled torque converter that was so monumentally susceptable to failure that it killed the version. Saab put high torque engines into chassis that would not really take it without making major changes [such as 4wd] and that was there screw up.

Thankfully the fixes are relatively simple and [with the exception of Abbotts' exellent viggen rescue kit] not too expensive.
 

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its not the fact that our trannies dont have equal lenght shafts although for someone who doesnt know saabs they might think that, and its certainly what i thought when i first bought my car.

The proper solution to THAT problem is actually a limited slip diff, not custom shafts, a custom shaft will only do so much to get rid of toque steer. That is IF thats the problem. In a saab its the steering rack that does most of that. Other things you can do to make it less are urethane parts for the control arms, even solid or stiffer motor mounts.
 

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its true a LDS could reduce torque stear but it has a habit of reducing stearing abillity around corners too as both wheels want to drive at the same speed causing the car to go straight on at corners, not funny :eek:
 

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nono thats not true

your thinking of a welded diff. In those cases the gear is setup in such a way that both tires spin at the same time all the time. So what happens is that the inside tire is actually spinning too fast for the inside and you get bad handling. Some diffs might be locking diffs that just lock under any load...

a limited slip is still a differential, meaning the two axles will rotate at different speeds, its just that under acceleration the limited slip shifts power from one wheel to the other depending on which wheel is spinning free/ faster.
 

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please dont take this the wrong way, but i know what and how a LSD works, i am, after all a gearbox engineer :lol: and have heard lots of stories about FWD cars with LSDs trying to go straight ahead when cornering in the wet, i suppose it all depends on how tight the diff is set up ;)
 

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ok i see, but its still a differential, certain types of diffs might not allow for good turning but most out there such as peloquin or quaife are better under turns not just acceleration
 

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9-3's do have equal-length half-shafts...
So, it's not that. I stick with the "shoddy rubber bushings" theory.

On that note, I RARELY have to fight mine to keep it Straight.
perhaps I'm just used to it From the Galant and my old 9000, but it's not even a thought. I worry more about the fuel-cut than anything.

people tend to have good luck with te genuinesaab VRK.. and last i heard, the MP wasn't so hot.
 

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My experience has been that the combination of steering rack brace and LSD can harness the dreaded torque steer. You can get tight radius steering problems with the Sellholm LSD as this is more of a true LSD. For daily street driving I prefer the Quaife LSD. I had a Quaife installed on my last '94 9000 Aero and under hard acceleration from a stop it would tend to squat down and launch straight.
 

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boxman said:
and have heard lots of stories about FWD cars with LSDs trying to go straight ahead when cornering in the wet, i suppose it all depends on how tight the diff is set up ;)
Drove a tarmac stage rally prepared Pug 205 Gti with a clutch pack LSD set quite tight.......:eek: :eek:

That was hard work I can tell you.....;oops:

The Quiafe LSD (actually a gear type torque biasing diff) is very good, as Kevin says, I had one in my 9000 Aero as well..(and in my Sunbeam-Lotus).
Driving down to Tesco's to do the shopping you wouldn't even know it was there, but load some torque into and it really pulled you around the corner...great bit of kit and worth every penny.
 
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