Oversteer on corners
Having finished the back end, I have been testing the car and discovered some unpleasant behaviour in corners. It seems the car wants to turn in more aggressively than I ask it to. This happens as the suspension is loading up into the bend. What it feels like is an amount of oversteer that is not caused by the rear end coming loose, and it requires minor correction every time. This makes the car difficult to steer smoothly, especially when driving in a spirited fashion.
A few points about the car:
What might be the cause of this oversteer?
A few points about the car:
- Has Kumho tyres all round - 165x13 with good tread, inflated to the correct pressure (23 PSI all round, I think).
- Front suspension joints all replaced (ball joints, track rod ends and trunnions / uprights), but not the wishbone bushes.
- Rear suspension bushes all replaced and CV jointed halfshafts fitted.
- No evidence of bump steer, so I think this isn't the root cause.
- I have attempted to set the tracking at the front, but it may be out.
- There is no free play in the steering column, or very little, but the column bushes definitely need to be replaced.
What might be the cause of this oversteer?
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JonB - Coveted Fifth Gear
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Your car should also have aluminium spacers that fit on top of the Chapman struts to bring the Aeon rubber springs into play earlier, do you have those?
What is the front and rear toe- in?
Do you have any other non standard front or rear components in the suspension?
A properly setup Plus 2 should be nice and neutral unless a corner is really stuffed up and then it hsould be gentle under steer.
Can you describe more the situation when you experience over-steer e.g. speed, type of corner, load in car throttle or braking situation etc
cheers
Rohan
What is the front and rear toe- in?
Do you have any other non standard front or rear components in the suspension?
A properly setup Plus 2 should be nice and neutral unless a corner is really stuffed up and then it hsould be gentle under steer.
Can you describe more the situation when you experience over-steer e.g. speed, type of corner, load in car throttle or braking situation etc
cheers
Rohan
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rgh0 - Coveted Fifth Gear
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Front Tracking
Rear Tracking
Front to rear alignment
Bump steer
John
lotus-suspension-f42/tracking-t19506.html
Rear Tracking
Front to rear alignment
Bump steer
John
lotus-suspension-f42/tracking-t19506.html
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john.p.clegg - Coveted Fifth Gear
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Hi John
I think there is no bump steer. Was wondering if worn bushes at the front might be the culprit. Anyway, I read that thread on tracking a while ago and tried to make my own gauge using the "old man's method", but I suspect I got it completely wrong.
Regarding the diagram on the first post, do I take it that I could set the front tracking by the simple expedient of making them in line with the toe in at the rear using a straight line?
I think there is no bump steer. Was wondering if worn bushes at the front might be the culprit. Anyway, I read that thread on tracking a while ago and tried to make my own gauge using the "old man's method", but I suspect I got it completely wrong.
Regarding the diagram on the first post, do I take it that I could set the front tracking by the simple expedient of making them in line with the toe in at the rear using a straight line?
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JonB - Coveted Fifth Gear
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- Joined: 14 Nov 2017
Jon
Yes,providing the rears are in the right place.....
John
Yes,providing the rears are in the right place.....
John
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john.p.clegg - Coveted Fifth Gear
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- Joined: 21 Sep 2003
I have set toe on many cars with string. Set up 4 jackstands or paint cans or w hatver you canattach a string to ahead and behind the car. Give yourself some space to measure distance between strings.make them parallel to each other and the car centerline. On the c/l. I just make sure they are all the same distance from the tires a nd parallel to each other taking into consideration that front and rear track width may not be same. Then just measure at front and rear of each tire. Relatively easy. Forty years of s uccess speaking here.
- Billmack
- Third Gear
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Adverse stackup of tolerances. That would be the engineering term. And looki g around I would not be surprised to see even spyder themselves offer adjustable control arns. Possibly if you have upper control arms back there you could have rear bump steer but unlikely. Front bumpsteer i do not consider all that important as one wheel is unloaded and the other you have control if by the steering wheel...as long as its not huge. Bad handling is produced by the rear wheel toing out under compression because you have no control over that.Even toeing in back there is not that bad. Out, well, the back of the car just winds its way up toward the fence.
- Billmack
- Third Gear
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- Joined: 30 Sep 2017
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