Drift alignment settings - toe

[wheels-inmotion]

Originally posted by Jim
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I have a site in the UK regarding geometry etc... but through pressure of the views i need to expand within the area of drift racing. my understanding of geometry and research has shown a very gray area, camber front yeh, camber rear yeh, castor??? but what about the rear toe!!!!!nowhere is there any information about rear toe settings? i have my own ideas, and they have been used by Nissan and Lexus with seemingly good results, but
i want to have someone to argue about the tech side, it's no good given advise if there is no one to validate it, "tell me" what setting would you use for a front wheel drive car in a drift race!!!!

[Jim]

Welcome wheels-in motion,

Good to have you involved. Before getting into detail of specific Drift toe settings for the rear, I'd like to bring peoples attention to the Whiteline FAQ dealing with toe at http://www.whiteline.com.au/faqsusp01.htm#Toe-in or toe-out.

There's also a case study following that discusses settings. The key issue we would like to highlight is concept of stability vs instability and how toe can be used to promote or de-promote same at each end.

Having said that, I am loathe to talk about generic "ideal settings" for any group of vehicles, it will depend on so many other factors. Secondly, with the question of ideal settings for a "FWD" drift car, are we having a purely hyperthetical debate for the sake of discussion or did you mean rear wheel drive?

Cheers

Jim

Whiteline Automotive

[wheels-inmotion]

wow, did i say front.. for sure i meant rear wheel drive, i would value your opinion toward my theory, this is, anti-clockwise drift with a 180 degree bend, 90 degrees on with full application of thrust with a full opposite lock, upper parralelogram pulled forward diagonally via castor, do you feel as i do that 30' negative partial rear toe will permit and allow to sustain the rear drift?. i agree it's not possible to type a one situation covers all post, but, the law of geometry exists whatever the car, the application of these laws is the only veariable. " i think".

[Wojtek]

Hi,

I don't quite understand what your theory is... do you mean to adjust rear toe settings such that to induce a thrust angle?
I'm not sure that this is necessarily desireable. This would result in a car that can drift better in one direction only. It also does no favours to car control, especially during change of direction. As I understand drifting "procedure", it is to provoke the car to oversteer with a combination of sudden steering and throttle inputs. The suspension and gemetry can help with this, and as Jim mentioned, the idea is to make the "loose" in the rear. Once the car is drifting, it is mostly a case of maintaining an oversteering attitude and rear wheel slip (as this is important for the show factor) with enough power/torque.

Regards,
Wojtek.

[wheels-inmotion]

Originally posted by Wojtek
Hi,

I don't quite understand what your theory is... do you mean to adjust rear toe settings such that to induce a thrust angle?
I'm not sure that this is necessarily desireable. This would result in a car that can drift better in one direction only. It also does no favours to car control, especially during change of direction. As I understand drifting "procedure", it is to provoke the car to oversteer with a combination of sudden steering and throttle inputs. The suspension and gemetry can help with this, and as Jim mentioned, the idea is to make the "loose" in the rear. Once the car is drifting, it is mostly a case of maintaining an oversteering attitude and rear wheel slip (as this is important for the show factor) with enough power/torque.

Regards,
Wojtek.
no? keep the thrust at 0 but have nagative rear toe ns/os, my theory is, once on a drift the tyre is subject to lateral resistance, if there is negative rear toe then that will allow for more "in drift" possition control, if the rear partial toe's are both set "say" 30' negative then the corner direction is not relevent, straight line drift according to my theory also will benifit,
example. straight line drift whats better
/ /
\ / or
/ /
| | i'm only suggesting the maintinance of the drift not how it's generated.

[Wojtek]

Hi,

OK. understand now.

With the car already in a drift state, weight is transfered to the inside rear wheel. So, having some rear wheel toe-out, the inside rear wheel will have more traction then the outside rear wheel as it has more load. This then has the effect of promoting oversteer or maintaing a drift state, as the inside rear wheel is trying to keep the car rotating about the inside front wheel.

hope this makes sense, but these are only my thoughts open for discussion.

Regards,
Wojtek.

[wheels-inmotion]

Originally posted by Wojtek
Hi,

OK. understand now.

With the car already in a drift state, weight is transfered to the inside rear wheel. So, having some rear wheel toe-out, the inside rear wheel will have more traction then the outside rear wheel as it has more load. This then has the effect of promoting oversteer or maintaing a drift state, as the inside rear wheel is trying to keep the car rotating about the inside front wheel.

hope this makes sense, but these are only my thoughts open for discussion.

Regards,
Wojtek.
perfect sence, at last i have a argument for the lack of rear toe, my theory was based on inertia, not the transfer of weight? still i feel that the rear toe being set negative will assist, and this is why? as you say initially the weight will be on the inside rear wheel, the inertia and application of thrust will evolve the oversteer, but.. as the drift slows i feel that the osr negative toe can continue the drift longer now that the weight value has diminished. what do you think?

[Wojtek]

I think we're on the same page here.

Yes, as the drift progresses, there will be a reduction of weight transfer, but as long as it is drifting there will always be more weight on the inside rear wheel then the outside rear wheel. That is why I suggested that some rear toe-out may assist in maintaining drift.

Argument 1.
So, rear toe-out on a rear wheel drive car IS a "loose" state, therefore it is easier to break traction.
Argument 2.
As the inside rear wheel has more weight, therefore more traction then the outside rear wheel, the sum of the forces of the two rear wheels, will try to rotate the car about the inside front wheel in the direction of more oversteer / drift.

Wojtek.

[wheels-inmotion]

Originally posted by Wojtek
I think we're on the same page here.

Yes, as the drift progresses, there will be a reduction of weight transfer, but as long as it is drifting there will always be more weight on the inside rear wheel then the outside rear wheel. That is why I suggested that some rear toe-out may assist in maintaining drift.

Argument 1.
So, rear toe-out on a rear wheel drive car IS a "loose" state, therefore it is easier to break traction.
Argument 2.
As the inside rear wheel has more weight, therefore more traction then the outside rear wheel, the sum of the forces of the two rear wheels, will try to rotate the car about the inside front wheel in the direction of more oversteer / drift.

Wojtek.
well ok, but just so i can get my sums correct? dont you mean " weight transfer to the outside wheel" not the inside??

[Wojtek]

I mean the INSIDE rear wheel.
During a drift, with opposite steering lock, the car is leaning into the corner and the inside rear wheel takes more load.

Wojtek.

[wheels-inmotion]

Originally posted by Wojtek
I mean the INSIDE rear wheel.
During a drift, with opposite steering lock, the car is leaning into the corner and the inside rear wheel takes more load.

Wojtek. naa, i'm well stuffed on this one??? do we have a UK/ USA NS/ OS brake down?

lock / /
drift > that way
inner | < there , how? can this wheel take more load?

[Wojtek]

It's easy to get confused, and difficult to explain with // >>\\
Another way of thinking about this, is that it is the opposite to steady state cornering during which weight is transferred to the outside wheels.
Have a look at some pictures.

Wojtek.

[KevinM]

The only way I can make the weight transfer work in my head, is to assume that the car is fighting to get back to no slip angle, rather than the driver fighting to keep the drift from becoming a spin. In other words, a drift is actually more like the first correction from oversteer, than it is keeping the car from rotating further. A drifter isn't pitching the rear out and trying to reel it in, he's pitching it out, then fighting to keep it there?

[wheels-inmotion]

Originally posted by Wojtek
I mean the INSIDE rear wheel.
During a drift, with opposite steering lock, the car is leaning into the corner and the inside rear wheel takes more load.

Wojtek.

i think i need to have some time off?... the posts here are realy good, but i think maybe i am working to meany forums? the info on reflection is in my face, but seemingly with my eyes shut.. sorry! the rear toe factor i think we can lay to rest But!!
lets get really complicated and apply castor/ or in the USA caster.
My theory here in the UK is for?, lets say for some masters in drifting has involved unusual geometry set-up. one of them being the castor... as we know the position of the castor will accelerate or decelerate the TOOT, and the steering axis will reflect this, by a small radii or large? So where do you go? positive castor/ steering arm behind wheel/ accelerated TOOT/ long axis, or? negative retracted TOOT short axis. The TOOT is adjustable on all cars dependant on the castor? i think that low castor is best for drift since the castor can develope the TOOT purely for drift???
what do you think.... pure theory i must add.

[Wojtek]

I'll have to think about that...
but can you explain how caster effects TOOT?

Wojtek.

[wheels-inmotion]

Originally posted by Wojtek
I'll have to think about that...
but can you explain how caster effects TOOT?

Wojtek.
I will try my best. lets concentrate on the lower parallelogram of the car and say osf UK drivers side.

there are two rotatinal pivots, lower swivel and track rod end, in addition there is the knuckle joint between the steering arm and steering rack.

as we know in the design stage the TOOT will be dependent on the steering axis, accentuated by angular intrusion, be it track rod end or what ever..
and we know TOOT is pre-set, but my theory is this.

Rear wheel drive (drift) car, steering arm behind the wheel.
Castor 6 degrees, TOOT inner wheel taken from 20 degrees = a sum of 21 degrees 30', pretty much common.

move the castor to 7 degrees, recover the toe displacement and the TOOT will have a new area for activation. the rotational point of the lower swivel has moved away from the knuckle joint, this means that the rotational axis of the steering arm is accentuated, purely by the extended distance between the lower swivel and the steering knuckle, the pivital point being the track rod end, this Will amplify TOOT.

For sure the lock angles will be affected but in drift the TOOT is a bigger player... purely theroretical, or is it??

[Wojtek]

I think I can follow your analogy, and in theory I would say that you are correct that increasing caster will increase TOOT. We will however try to measure this on a wheel aligner jig next time we have an opportunity, firstly to confirm your theory and if so to measure how much.
This doesn't really answer if this is it is beneficial for drifting or not... more to think about.

Wojtek.

[wheels-inmotion]

Originally posted by Wojtek
I think I can follow your analogy, and in theory I would say that you are correct that increasing caster will increase TOOT. We will however try to measure this on a wheel aligner jig next time we have an opportunity, firstly to confirm your theory and if so to measure how much.
This doesn't really answer if this is it is beneficial for drifting or not... more to think about.

Wojtek.
For sure! i hope to test this on some drift cars soon, and i will let you know that they think?