Online car/suspension/chassis set up guidance
Discussion
Hi,
Can anyone point me in the direction of some online info regarding car setup.
I've recently completed a Stuart Taylor Locoblade, for use on trackdays etc. I'm suffering a little information overload after reading a few books on suspension/setup.
The car has got coilovers, camber adjust (front and rear), toe (front obviously and rear). I've set all the variables to a base line as a start but now want to improve my knowledge on what does what. I know there's no substitute for testing/experience, but every little helps.
The books can be a little vague sometimes.
I want to know things like if you adjust "x" the car does "y". Or if you want the car to do "A" tweek "B" etc etc etc.
Following a shakedown yesterday, that car was very twitchy/nervous in a straight line at high speed. More toe-in rear ? (currently 1mm)More toe-out front ? (currently 1.5mm)
Much as I value the advice given on forums like this. I don't want to be on here every day clogging up the threads asking silly questions like "what will happen if I add another 0.5deg camber", "what about another two clicks soft at the front" etc etc.
I've done a few trackdays in another car, but want to learn a bit more to get the best out of this car.
Thanks in anticipation
Can anyone point me in the direction of some online info regarding car setup.
I've recently completed a Stuart Taylor Locoblade, for use on trackdays etc. I'm suffering a little information overload after reading a few books on suspension/setup.
The car has got coilovers, camber adjust (front and rear), toe (front obviously and rear). I've set all the variables to a base line as a start but now want to improve my knowledge on what does what. I know there's no substitute for testing/experience, but every little helps.
The books can be a little vague sometimes.
I want to know things like if you adjust "x" the car does "y". Or if you want the car to do "A" tweek "B" etc etc etc.
Following a shakedown yesterday, that car was very twitchy/nervous in a straight line at high speed. More toe-in rear ? (currently 1mm)More toe-out front ? (currently 1.5mm)
Much as I value the advice given on forums like this. I don't want to be on here every day clogging up the threads asking silly questions like "what will happen if I add another 0.5deg camber", "what about another two clicks soft at the front" etc etc.
I've done a few trackdays in another car, but want to learn a bit more to get the best out of this car.
Thanks in anticipation
I think the GPL guys get heavily into this sort of thing. You may have overdosed on books, but if you don't have it 'How to make your car handle' by Fred Puhn is a good introduction to the theory, and how to put it into practice. Incidentally, toe out on the front is a little ... unconventional ... 
for a rear wheel drive car and may be contributing to the high speed handling problems?
for a rear wheel drive car and may be contributing to the high speed handling problems?Just a last minute adjustment at the end of the session yesterday.
Was set to zero up front, and will be put back when I make some adjustments to the rear.
More toe in rear, is supposed to stabilise it a bit so I've read??????????????
But hey, what do I know ;-)
>> Edited by lchris21 on Sunday 20th February 21:24
Was set to zero up front, and will be put back when I make some adjustments to the rear.
More toe in rear, is supposed to stabilise it a bit so I've read??????????????
But hey, what do I know ;-)
>> Edited by lchris21 on Sunday 20th February 21:24
In my experience Green V8s is correct.
The principle is on a RWD you are pushing the front wheels which will result in the toeing out under drive.
The rears (as a result of pushing) will do the opposite.
On a RWD I would expect to see fronts toed in by 1-2mm and the rears parallel or possibly slightly toed out.
Any stability problems are probably caused by the front not the rear. Have you tried dialing in a bit more castor. It may also be worth looking at the height to see if you have an optimum ride height for the geometry.
The principle is on a RWD you are pushing the front wheels which will result in the toeing out under drive.
The rears (as a result of pushing) will do the opposite.
On a RWD I would expect to see fronts toed in by 1-2mm and the rears parallel or possibly slightly toed out.
Any stability problems are probably caused by the front not the rear. Have you tried dialing in a bit more castor. It may also be worth looking at the height to see if you have an optimum ride height for the geometry.
Toe out on the front is quite often used on hillclimb/sprint cars (including Seven types), to make them feel more pointy.
My Sylva Clubmans is set to toe out at the front, and it is a bit twitchy, but manageable, in road use. The reason GreenV8S views it as unusual is probably because the last thing you'd want to do to a TVR is make it less directionally stable!
Joking aside, though, if you want stability, set the car to toe in.
Damper settings can have an awfully big effect on perceived stability, though, and I'm afraid that you have no real option but trial and error, unless you want to get involved in some really complex mathematics. As a starting point though, begin with the fronts set slightly stiffer than the rears.
I don't know about online resources, but the Carroll Smith books include testing/set-up guidance of exactly the sort you are after: ie. 'increase X and Y will be the result'.
Edited to add:
...oh, and if you want stability, DO NOT set the rears to toe out, either. This will lead to directional instability at the rear,with potentially very hairy results. Parallel or a little toe in at the back, as well.
...and if you have broadband and want to e-mail me through my profile, I'll scan the 'cause and effect' listings from Carroll Smith's book and mail them back to you.
>> Edited by Martin_s on Monday 9th May 19:12
My Sylva Clubmans is set to toe out at the front, and it is a bit twitchy, but manageable, in road use. The reason GreenV8S views it as unusual is probably because the last thing you'd want to do to a TVR is make it less directionally stable!
Joking aside, though, if you want stability, set the car to toe in.
Damper settings can have an awfully big effect on perceived stability, though, and I'm afraid that you have no real option but trial and error, unless you want to get involved in some really complex mathematics. As a starting point though, begin with the fronts set slightly stiffer than the rears.
I don't know about online resources, but the Carroll Smith books include testing/set-up guidance of exactly the sort you are after: ie. 'increase X and Y will be the result'.
Edited to add:
...oh, and if you want stability, DO NOT set the rears to toe out, either. This will lead to directional instability at the rear,with potentially very hairy results. Parallel or a little toe in at the back, as well.
...and if you have broadband and want to e-mail me through my profile, I'll scan the 'cause and effect' listings from Carroll Smith's book and mail them back to you.
>> Edited by Martin_s on Monday 9th May 19:12
Martin_s said:
The reason GreenV8S views it as unusual is probably because the last thing you'd want to do to a TVR is make it less directionally stable!
Careful what you say about TVRs man. You don’t want to be flamed now do you
Martin_s said:If you have the book to hand could you post the ISBN number please. I'd like to get a copy.
...and if you have broadband and want to e-mail me through my profile, I'll scan the 'cause and effect' listings from Carroll Smith's book and mail them back to you.
Carroll Smith: Tune to Win
My copy (some years old) does not show an ISBN number. Instead, it has an American Library of Congress Catalog Card Number: 78-73549.
I'm sure a quick search on Amazon would turn it up, but failing that it is listed on Mill House Books' website: www.millhousebooks.com/osb/showitem.cfm?Description=Tune+to+Win&Message=1
My copy (some years old) does not show an ISBN number. Instead, it has an American Library of Congress Catalog Card Number: 78-73549.
I'm sure a quick search on Amazon would turn it up, but failing that it is listed on Mill House Books' website: www.millhousebooks.com/osb/showitem.cfm?Description=Tune+to+Win&Message=1
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