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Discussion Starter · #1 ·
Hi, A question came up at work to day, about front wheel drive cars and Torque Steer ( to much Ford Focus talk ).
So how is for you Guys with over 300BHP ?
 

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Torque steer is a major problem in my aero and the cars only putting out just under 300bhp last time on the dyno. Have since had a big I/C fitted so more bhp = more torque steer
I imagine some of the other monster turbos on this forum have a lot more


Zahid
 

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Originally posted by ZARS:
[qb]so more bhp = more torque steer [/qb][/b]
Surely more torque = more torque steer??

If you get extra horse power high up the rev range with a big turbo, you do not necessarily get more peak torque.
 

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There's lot's of complicated theory about torque steer and it's causes but basically it cna be put down to one of two causes:

- Different driveshaft lengths or
- Suspension flex

Obviously the first is pretty self explanatory but the 9000 and other models, AFAIK have equal length driveshafts.

So that leaves us with suspension flex. I use that term very loosely as it encompasses a whole range of scenarios.

Basically, it's largely about the fact that the "force" to accelerate gets applied differentially outside the centre line of the steering, and thus results in a pull to one side.

Worn suspension can make it worse; conversely those of us with poly bushes, stiffened suspension and engine mounts suffer less from it.

I knock out around 360lbft and most of the time it's not a major problem. Yes you need to keep your hands firmly on the steering wheel, but it's not a major battle...
 

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what torque steer....??
Honestly with the quaife lsd and tied down suspension I really do not get much at all
Mr Clarksons recent "demonstration" of what torque steer was on top gear showed it up to be a pretty minor thing. however it was not always like this ...
I remember when I first tweaked it and a spirited take off up a slip road on to the M62 saw me fight to keep it to one lane !!
(the fact that there was a porsche carrera 4 in the other lane had nothing to do with it ..)
It was a handfull and that was with the lsd
It has got better as I have replaced all the bushes with poly and fitted a 1" a/r bar at the back
Probably the thing that had the biggest influence was the strut brace...
I also keep the koni's at about half a turn on the font and almost full on at the back and this gives me the best traction/ride
you do need to try a few things out till it suits you...

and this is with 400+ hp and 400 + ft/lbs of torque....
 

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Surely more torque = more torque steer??

If you get extra horse power high up the rev range with a big turbo, you do not necessarily get more peak torque.  [/b]
Doh! That's what I meant And I guess the new I/C will add a bit more torque, well certainly feels that way in all gears

Zahid
 

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Sounds like I should get my suspension sorted. I have the poly bushes, strut brace and bigger rear arb but still get a fair bit of torque steer. Still on stock suspension though.

As Bubbles suggested perhaps gripping the wheel tighter might help instead of having one arm hanging on the ledge in a laid back style

no I don't really drive like that
 

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As my name suggests, my car was a Torque-Steering beast until I sorted the suspension. Probably the thing that made the single biggest difference was renewing the front frame bushes with poly ones. But I guess it can just depend upon which bushes are most worn/degraded on your car.
 

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Believe it or not, so was my wife's old 55bhp 1.3 Polo
- very unequal length driveshafts meant under accelaration it pulled one way (towards oncoming traffic IIRC) and on the overrun, towards the ditch. The G-force with WOT in 2nd was incredible...
 

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Originally posted by Fliptop:
[qb]Believe it or not, so was my wife's old 55bhp 1.3 Polo    
   - very unequal length driveshafts meant under accelaration it pulled one way [/qb][/b]
And, IIRC, the 99 turbo has unequal driveshaft lengths giving some great torque-steer and leading to the journalistic cliche of every Saab turbo ever since to be some sort of torque steering monster
 

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decided to do some torque steery tests on the way home tonight
full power take offs (almost) No drama ..little tugging from side to side which you can hold with two fingers
I was amazed ....

thinking what would cause a torque teer effect

My guess is the wishbone bushes front and rear
if there is any difference in compliance side to side ...my guess it would veer off in one direction
I think as long as they are the same things should be ok
any misalignment would be amplified as well
 

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Add to your list - road surface imperfections (esp. for those with no LSD...), white lines & camber

If a GM900 or 9-3 - bulkhead flex


My 9-3 LPT was a bit lairy on uneven surfaces, especially in 3rd & 4th gears (road speed may have something to do with it too when road surface is a factor I guess - you hop from one side of the road to the other faster if you're going quickly)

The 9-5 is marginally better but it also has a lot more torque. On billiard table tarmac it's absolutely fine...

On 99s it might also be that as the rear axle moves to one side with the suspension under compression (the panhard rod encourages this) that effectively alters the 4-wheel alignment??
 

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Originally posted by Fliptop:
[qb]On 99s it might also be that as the rear axle  moves to one side with the suspension under compression (the panhard rod encourages this) that effectively alters the 4-wheel alignment?? [/qb][/b]
The C900 and 9000 have the same arrangement.
 

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I know 900s are basically the same, wasn't aware of 9000s as I've never had one!

Am I right in thinking the sideways movement effect was reduced on 900s and later 99s/90s with the changes to the rear axle?

I know the tyres tend to touch the wheel arch on one side more than t'other...
 

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I reduced torque steer in my standard aero by doing the following -
1. Poly rear wishbone bushes (next time I am working on that area, front bushes are going in)
2. Smoked side repeaters (made the biggest difference)
3. good tyres - put some Eagle F1's on and i barely get any wheelspin now.
4. Put a strut brace on order - frightened the torque steer out of the car!
 

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Discussion Starter · #17 ·
2. Smoked side repeaters (made the biggest difference)[/b]
Now this is something that I have tryed, if you only put the SSR on the O/S it seems to remove TS altogether.
 
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