More geometry setting questions...

[Kooga]

Hi guys,
I'm going to get my suspension aligned soon, (probably at that colchester place recommended). I've seen the settings on the sticky, but just wanted to ask which of these is best for a pretty much std car with 15" wheels -TRD or Factory? Or Neither??! Are there any recommended tweaks to these settings?? Car feels a bit skittish at the front at the mo, so hoping for an improvement...(p.s, suspension has been replaced before you ask!!)

[System-G]

Factory is the best place to start with.

I would only use anything else if the car was tracked fairly regularly, There is a likely possibility of tramlining & bumpsteer on the road using "race" settings.

[Jim-SR]

stock setup sucks, id start somewhere better

if the car is purely a road car then go for the following...

front camber = 1 to 1.5 degs
front toe = 1mm toe-in
front castor = maximum adjustment, same side to side

rear camber = 1 deg
rear toe = 3mm toe-in

if you track the car or want to go a little more hardcore then run 1.5 to 2 degs front camber, 1.5 degs rear, run the front toe parrallel, and the rear toe 2mm in, and back the front castor off a bit (people go crazy on front castor, but it messes the handling up if you go insane, you shouldnt need 6 degs+)

[System-G]

stock setup sucks, id start somewhere better

Based on what grounds?

[Kooga]

Why do you think the stock set up is rubbish fella??

[Jim-SR]

on the grounds that you can improve it. stock is ok, works for someone who wants to just drive around with minimal tyre wear. if you want to improve the response and increase grip then youll want to move away from the stock settings (which state something pathetic like +/-0.17 degs front camber if memory serves correct, i think its an odd number like that)

i ran my car at the settings i quoted on the road for the best part of a year. it never had any issues with tramlining or adverse handling, it wore the inside edge of the tires slightly faster than the outside but not by an unreasonable amount, and was more responsive and offered more grip (my "standard" setting werent exactly factory fresh, cambers were fairly close but rear toe was messed up on one side from a slightly bent tie rod, front toes were fairly close too iirc because they had been set previously.

the MR2 was designed as a cheap and lightweight daily runabout, for people to commute to work in. it wasnt designed to be a sports car, regardless of what some people seem to think. the geometry was specced for minimal tyre wear and minimal drag (e.g. maximum fuel economy). it can be improved upon very easily

[System-G]

@ your last paragraph Jim.

I've driven a couple of AW11's on stock set-up on road & track and it's been fine. As you say, it could be improved on but 90% of owners (including those who would do a couple of trackdays a year) wouldn't know the difference between stock and slightly tweeked.

The TRD setting were used for a while as a benchmark for track & race, but even they have been "improved" upon over time.

One of the best handling AW11's I drove on circuit was set up at Powerstation in Cheltenham. At the time the geo was being done the owner was asked how he wanted the car to handle and they did the geo not using stock or TRD settings but their own knowledge of the cars and racing experience. To date no one knows what settings were actually used and they forgot to take the printout.
The only thing i can say is the car handled like it was on rails and completely neutrual - no under/oversteer whatsoever.

Like I said to the OP, start with stock and take it from there. If you don't like the way it feels on the road with stock settings, get the place to make necessary adjustments.

[jimi]

I think a lot depends on your style of driving. Since I fitted MK3 wheels with 195 x 50 F1's I've been more than happy with my set up, in fact when I've been out on runs several people have remarked on how well it handles ( and I don't drive slowly on runs )
I'm going to be fitting a new steering rack and replacing the rear tie bars, so I decided to get the set up up checked and recorded so I could get it set up the same once I've change the parts. The checks showed my set up to be almost exactly standard apart from the drivers rear camber being a few minutes out.
Needless to say I'll be sticking with standard when I get it set up again,
A major part of the MK1's reputation has always been it's handling, almost all the reviews / comparisons I've read have praised the MK1's handling (on standard set up) I reckon Mr T got it pretty much spot on for fast road use which is what most people want IMHO and my vote would be for standard

[Kooga]

Thanks guys, though I must confess I am probably more confused now!!
I think probably best thing is to start with std and see whether it actually does suck or not!! Then I know what to try next
BTW, is there anywhere cheap to get a new pair of rear tie bars/tca's/whatever they're calleds so that the rear toe can be adjusted...mine look a bit grotty and i can't imagine they'd adjust easily!

[System-G]

I just bought a pair off SBITS (through twosrus.co.uk) and am so impressed by the quality. Awesome bit of kit

[nicedude1976]

In my experience there is no point going over 1.2mm toe in PER SIDE on the rear, otherwise you will shag your tires more with little benefit. Aynone with different experience as to "stability" is welcome to post.
If you want to track it, and you should set front camber around or a bit steeper that -1deg, rear at least the same. You will feel the front on the steering though (in a nice though not necessarily relaxed way).

[NDR008]

stock setup sucks, id start somewhere better

if the car is purely a road car then go for the following...

front camber = 1 to 1.5 degs
front toe = 1mm toe-in
front castor = maximum adjustment, same side to side

rear camber = 1 deg
rear toe = 3mm toe-in

if you track the car or want to go a little more hardcore then run 1.5 to 2 degs front camber, 1.5 degs rear, run the front toe parrallel, and the rear toe 2mm in, and back the front castor off a bit (people go crazy on front castor, but it messes the handling up if you go insane, you shouldnt need 6 degs+)

I agree the stock settings are set for minimal wear and a good compramise of fun and safety.

However geo settings need to suit the driver style and skill.

I've had trouble figuring this out - your proposed camber settings - are they -ve?

[crazybrightman]

probably not much use but my track car is 1.5-1.6 rear and around 1.7-1.8 front. caster needs backing off though imho. toe is massive at the front 3mm but will back to 1 the track rod wouldn't wind in any further so need to sort them out.
rear track is around 3mm and gives and nice balance to very slight over steer.

[System-G]

I am currently running our track car the following

Front toe-in (on 15" wheels) = 1.2mm total approx
Rear toe-in (on 15" wheels) = 2.6mm total approx
Front camber = -1.0 deg
Rear camber = -1.5 deg
Castor = approx 5.5 deg

It's a vast improvement on how it used to handle. It still suffers a bit of bump-steer & minor tramlining on the road, but on track it's awesome. On rails.

It also has the following to help
> New poly bush set
> 5-way adjustable Tociko shocks (set to 5 (full hard) rear and 4 front)
> TRD topmounts
> -30mm springs
> 19mm rear ARB
> New ball joints
> New Droplinks
> R888 rubber

[D]

I am currently running our track car the following

Front toe-in (on 15" wheels) = 1.2mm total approx
Rear toe-in (on 15" wheels) = 2.6mm total approx
Front camber = -1.0 deg
Rear camber = -1.5 deg
Castor = approx 5.5 deg

It's a vast improvement on how it used to handle. It still suffers a bit of bump-steer & minor tramlining on the road, but on track it's awesome. On rails.

It also has the following to help
> New poly bush set
> 5-way adjustable Tociko shocks (set to 5 (full hard) rear and 4 front)
> TRD topmounts
> -30mm springs
> 19mm rear ARB
> New ball joints
> New Droplinks
> R888 rubber

Hi, have you tried r888s with higher (negativ) camber?
http://toyotires.com/tire/pattern/proxes-r888
Here You can see camber should be 2,5
One of my friend is using r888 on his ae86, he told me he didn't get enough grip until he using extrem cambers.

[System-G]

I don't think - 2.5 is possible on the AW11 without adjustable topmounts or other suspension mods.

Also the stated hot temperature is too hgh for the AW11. running 32+ psi hot on the MR2 makes for the tyres to go off far too quickly. You'll find after about 15 minutes grip levels seriously reduce. The centre of the tyre will also wear extrememly quickly. 28psi hot is as high as you really want to go.
We set the similar pressures on Elise & Exige track & race cars.
Even when we were doing comparisons on Caterhams using Toyo R888, Yoko 048R and Avon ZZR, pressures were set at 21psi hot.

What the Toyo site is stating is probably based on a specific car and it won't be applicable to others.

[D]

I don't think - 2.5 is possible on the AW11 without adjustable topmounts or other suspension mods.

Also the stated hot temperature is too hgh for the AW11. running 32+ psi hot on the MR2 makes for the tyres to go off far too quickly. You'll find after about 15 minutes grip levels seriously reduce. The centre of the tyre will also wear extrememly quickly. 28psi hot is as high as you really want to go.
We set the similar pressures on Elise & Exige track & race cars.
Even when we were doing comparisons on Caterhams using Toyo R888, Yoko 048R and Avon ZZR, pressures were set at 21psi hot.

What the Toyo site is stating is probably based on a specific car and it won't be applicable to others.

Ok I realised you have much more trackday experience than me. So, my English not the best. Please check me if I understand everything well:

It looks good for me to start from where you are:
Front toe-in (on 15" wheels) = 1.2mm total approx
Rear toe-in (on 15" wheels) = 2.6mm total approx
Front camber = -1.0 deg
Rear camber = -1.5 deg
Castor = approx 5.5 deg

My Q:
Castor = approx 5.5 deg - Is that the maximum at you?
Maybe i should use more negative camber, if my hot pressure is under 28psi?
I know that stupid Q but about when should I measure hot pressure? After 10-15 minutes? Cold pressure at you? (cold weather will be around 10-15c)
Front toe-in looks a little much for me? Could you explain why is it good?
I don't really understand why are You using bigger rear camber ?

(My setup (differences highlighted)
> New poly bush set
> 5-way adjustable Tociko shocks (set to 5 (full hard) rear and 4 front)
> oem topmounts
> TRD springs, actually there wasn't any lowering I think
> whiteline 18 front 20 rear adj. ARB
> New ball joints
> New Droplinks
> R888 195/50 r15rubber )

Thanks for All

[System-G]

I basically started with the TRD race/trac settings and then dialed out rear toe a little. It felt good so I left it be

[Lauren]

I'd say run zero toe-in on the front, ie parallel. Makes the car more 'pointy' and easier to turn-in though MK1s always understeer and aren't renowned for a good turn-in.

As Garrick says there is a limit to how much camber you can achieve with the standard camber bolts. I found swopping them from side to side allowed me to achieve a bit more.

Castor is largely irrelevant to a point given that the faster you are going the less impact it has (ie less steering input). So don't get hung up on castor.

[D]

I'd say run zero toe-in on the front, ie parallel. Makes the car more 'pointy' and easier to turn-in though MK1s always understeer and aren't renowned for a good turn-in.

As Garrick says there is a limit to how much camber you can achieve with the standard camber bolts. I found swopping them from side to side allowed me to achieve a bit more.

Castor is largely irrelevant to a point given that the faster you are going the less impact it has (ie less steering input). So don't get hung up on castor.

You are right about the front toe-in, i think. I should try. It looks a good idea, there have to be a reason why others doesn't use it.
I made the lower hole bigger, so i can make more negative cambers now.

You sold your SE. That's very sad .