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Old 14 January 2016, 07:29 PM
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d.kenny
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Default Classic geometry settings

Hi all

I want to make my car handle better as its wuite frankly annoyed me on the last few track days

I have bc coilovers with swapped top mounts for castor

Iv flipped the bottom arms mounts tound 180

Have strut braces and adjustable lateral arms at rear

Arb are both standard i think

Car was very low so raising it up to a setting iv seen on here

345 rear and 350 front

When i take it for alignment though does anyone have anything to go buy...she is a track only car has a cage and that in in and no interior

I keep trying to make it faster but its pointless if i cant go round a corner

I noticed a massive difference ftom Doing the castor mods even on the road but im going mallory next month and want to improve it! I know how it was there before and i think anything will be an improvement!

Cheers
Old 14 January 2016, 07:48 PM
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InTurbo
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Might be a good read for you if you not already seen it.

http://www.pcadynamics.com/app/downl...+-+Insider.pdf
Old 14 January 2016, 08:57 PM
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d.kenny
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yh

Il re read that and have a go

Just didnt know if anyone has some basic settings for hard/soft on coilovers aswell and what to do if i feel such and such haha

I messed around with them at donnington but no matter what i did car was slippy as anything...track was wet but it was verging on uncontrollable...prob because to low...snapped from understeer to oversteer and drifting etc

Was good for messing about but very poor as lap times go

Also has dccd

Its type r running gear in saloon shell (i wrote type r off)
Old 15 January 2016, 09:48 AM
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https://www.scoobynet.com/suspension-12/918196-geometry-settings.html

There is a setup on here i wanna use as a basis

Does anyone know anywhere in or around coventry that has hunter alignment equipment?
Old 16 January 2016, 03:54 PM
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alcazar
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Stiffer rear arb, the next size up from the front, dials out understeer. Leave front standard.

I assume you already have solid droplinks?


Then take it somewhere like Carnetix, they will discuss what you want, set it up, test it, then let you try it so that you are satisfied.

DO NOT expect the same from back st Joe's KwikFit etc, just because you have some settings.
Old 16 January 2016, 06:28 PM
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Originally Posted by alcazar
Stiffer rear arb, the next size up from the front, dials out understeer. Leave front standard.

I assume you already have solid droplinks?


Then take it somewhere like Carnetix, they will discuss what you want, set it up, test it, then let you try it so that you are satisfied.

DO NOT expect the same from back st Joe's KwikFit etc, just because you have some settings.

Yes solid drop links

I measure rear arb at 20mm

Front is 19mm

Is that standard?
Old 03 February 2016, 10:21 AM
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i have raised the suspension up over the past few days

rear 345mm front 350mm

bottom arms look like they are at a much better angle now

problem is the way the rear wheels sit in the arch though now...one has more camber than the other...last night i tried to loosen the one side off that has less and kick hub over and tighten back up to achieve more camber and it did not work...only thing i can think is that the lateral arms at the rear are shorter on the one side

i dont know whether to spend a bit of time and try and set tracking up at rear with guages and then do front the same and then use string to get it parallel (free and unusure if i will get it completly straight)

or have it done by the likes of protyre in warwick (140 quid worse case)

im reluctant to spend the money at protyre at the minute though as i have a wr1 rack that is supposedly a quick rack i intend on refurbing and fitting and also the tyres currently fitted are ****...i was planning on using them for this one track day and then get some new ones next time (to get ready for this day has ended up costing me about a grand so far...not cheap fun at that!)

can anyone enlighten me on diy tracking and using string...i have no camber gauge though!
Old 22 February 2016, 07:32 AM
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d.kenny
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update

i completed the trackday without to many hiccups

before i went i set traking up with castor and camber etc to a setting i found on here that was quite aggressive

inthe morning it was damp/wet and my suspension was set quite hard so i softened up a bit (even though i was having more fun drifting but was gettin bollocked for it) and it was a bit better

in the afternoon when it dried up i was getting around the track ok but i cant help but think it could of been better

il explain as best as i can and see what you think as i dont know whether to buy some sticky tyres like yoko ad08r or nankang ns2r or a stiffer rear arb aswell/first
car currently has 225 45 17 toyos that dont scrub

anyway on corneriing when dry car just seems to massively understeer...im not sure if this is because im pushing to hard or suspension needed to be stiffer somewhere or it was just **** tyres

it feels really sloppy

it doesnt really oversteer on power when corneriing unless i initiate it even with the diff set to open

it does feel light on the back end under braking (which id expect but then with it going from lift off oversteer to massive understeer)

just feels like im driviing on plasticine or something

anyone have any recommendations?

it did seem to get better as they day went on...maybe tyres started to grip better when feathering up or i was just getting use to it

i want it to feel like a go kart though...not a boat

tyre pressures may of been a bit hard i dont know

think i was 34 on front and 32 at rear

really want to get it handling well...seems to have good enough bits to make it better!
Old 22 February 2016, 08:17 AM
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Post up your Geo setting,and any other suspension modifications you have.

If you don't have the settings it won't cost you much just to have a check to see where it is. Some places even do the check free.

Tyres will make a big difference on the track, I had toyo t1r many years ago and they were very soft and understeered a lot. But that was on a blobeye.

I also run Ad08r on my car in the warmer months and there fantastic, very firm sidewalls super sharp turn in, and more grip than your ever need on the road.

Last edited by InTurbo; 22 February 2016 at 08:20 AM.
Old 22 February 2016, 08:48 AM
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d.kenny
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Originally Posted by InTurbo
Post up your Geo setting,and any other suspension modifications you have.

If you don't have the settings it won't cost you much just to have a check to see where it is. Some places even do the check free.

Tyres will make a big difference on the track, I had toyo t1r many years ago and they were very soft and understeered a lot. But that was on a blobeye.

I also run Ad08r on my car in the warmer months and there fantastic, very firm sidewalls super sharp turn in, and more grip than your ever need on the road.
Suspension is as above

I set up myself the tracking using supertracker stuff

Camber front and rear was 1.9 degrees i think

Toe front and rear was 1 degree i think in

I didnt want to pay for a geo setup as i new my tyres were ****

The turn in was very sloppy

Id be inclined to say that was due to the tyres folding as opposed to staying upright and the suspension compressing instead and loading the tyre up or thats what it felt like

Maybe with better grippy tyres the car may oversteer more as it will grip better and bite or should i be looking at a rear arb to?

Bc coilovers
Standard front and rear arb
Solid drop links
Hardrace adjustable everything at rear
Flippped top mounts
Flipped bottom arm rear mounts for castor
Newage sti wheels and 225 tread (they dont rub)
Suspension raised to 350/345 i think it is

Everything as per previously explained!

Cheers
Old 22 February 2016, 08:51 AM
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I tried to get as close to this as i could<br/><br/>Think i have slightly more camber and a bit more toe<br/><br/>I dont think you can set normal laserline stuff as accurate on the toe as what this is can you?<br/><br/>Was just toeing in ever so slightly front and rear
Old 22 February 2016, 07:15 PM
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Originally Posted by d.kenny
Suspension is as above

I set up myself the tracking using supertracker stuff

Camber front and rear was 1.9 degrees i think

Toe front and rear was 1 degree i think in

I didnt want to pay for a geo setup as i new my tyres were ****

The turn in was very sloppy

Id be inclined to say that was due to the tyres folding as opposed to staying upright and the suspension compressing instead and loading the tyre up or thats what it felt like

Maybe with better grippy tyres the car may oversteer more as it will grip better and bite or should i be looking at a rear arb to?

Bc coilovers
Standard front and rear arb
Solid drop links
Hardrace adjustable everything at rear
Flippped top mounts
Flipped bottom arm rear mounts for castor
Newage sti wheels and 225 tread (they dont rub)
Suspension raised to 350/345 i think it is

Everything as per previously explained!

Cheers

Hope you don't have a degree off toe! Lol

If your having trouble with understeer first port of call would be a slight increase in rear bar diameter, as mentioned by Alcazar, this will help increase load transfer across the front axle and find you a bit more front end grip,

A set of more track orientated tyres would make a massive improvement. The firmer side walls will help improve steering response and won't roll over during hard cornering,

On the alignment side of things, I would personally have more camber up front than in the rear. Should make the car more neutral on the limit and help dial out understeer.

If you have flipped top mounts and bottom arm brackets you should have a fair bit of extra castor, So you should get quite good dynamic camber when steering without having to run high static camber angles that come with there own problems like straight line traction, braking and tramlining.

I would think a lot of toe in wouldn't be suitable for track work,
A slight bit helps on bumpy road to keep the car composed but having two much makes the car feel numb and unresponsive.

A good road set up won't work well on a track and vice versa.

I would try something like the following, one and half degrees up front and a degree in the rear.

(In degrees and minutes )

Front camber -1.30
Front toe 0.00
Total 0.00

Rear camber -1.00
Rear toe in 0.03
Total 0.06

Thrust angle 0.00

Rear bar set on medium to start off with to see how you get on.

Darren

Last edited by InTurbo; 22 February 2016 at 07:17 PM.
Old 22 February 2016, 07:24 PM
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d.kenny
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That is good info cheers!

Il get some tyres fitted and take it to prodriver i think its called in warwick (who did the subaru write up as they are local to me)

Il try and get arb to before i go and fit that

Car is really only used for track work

I stick trade plates in now and then but literally to potter to get fuel and tracking etc done

I take on recovery truck to and from track so im not left in the ****e

I think they should know in warwick what to set it at

Car dows feel sloppy to turn in

Probably is down to bad tyres id guess

Its a hell of a lot better than previous but like i say i think it can do better

What rear arb size should i get as i dont really wanna buy one then have to buy another?

Id prefer second hand to if at all possible 😂😂
Old 22 February 2016, 07:30 PM
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As your running the standard front bar go for a adjustable 22mm rear.
Old 22 February 2016, 07:40 PM
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Why is it worth putting a thicker front one on aswell as an even bigger rear then

If iv gotta get the stuff i dont want to have to buy twice in the future
Old 22 February 2016, 08:20 PM
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So a roll bar helps control lateral body movement, and can be used to tune a cars oversteer/ understeer balance by increasing or decreasing load transfer across the front or rear axles,

So if you fitted a larger rear bar it would add roll resistance to the rear,
This would mean lateral forces from cornering would be pushed towards the outside wheel on the front.

This would help put weight on the front outside tyre improving its grip and reducing understeer.

Like wise if you increased the front bar resistance and left the rear alone you would push the lateral forces to the rear outside wheel increasing rear grip and reducing oversteer.

If you were to increase the size of the front and rear bar simultaneously by the same rate the cars oversteer/understeer balance wouldn't change.

You will feel this weight transfer on the opposite axle as soon as you increase your bars resistance setting.

I only have two setting on my rear bar, on the stiffer of the two the front really darts into corners as there's more load across it.

So as you can imagine having a greater weight transfer through stiffer bars and springs will overwhelm a soft walled tyre.
Old 22 February 2016, 08:28 PM
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Originally Posted by d.kenny

Il get some tyres fitted and take it to prodriver i think its called in warwick

I think they should know in warwick what to set it at

The lads in Warwick pro tyre don't know much about set up, they just put oem setting on unless you have your own setting you want on.

Peter Cambridge can meet you there if you want a custom set up, he charges around £140ish.
Old 22 February 2016, 09:18 PM
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It really is about finding the right balance for the suspension and tyres then

Im looking for the front end to change direction quicker

Im no racing driver but i just feel that the car could be a lot better

Its so unresponsive and slow to turn at the minute

Im on a hunt for a rear arb at least then and il sort some tyres and go from there i think

Ftr an m3 driver who i was having a good go with came up at one point and commented on how quickly the car pulled from the hairpin and that it took him the rest of the lap really to get back behind

I followed him for a bit though and on gerrards he was noticeably quicker and more planted through the turn...mine was a handful to keep balanced and was just sliding around...was hard work and seemed to constantly be fighting with the car to find grip and a speed it would turn at

Like i say i dont know if this is solely down to **** tyres or what
Old 22 February 2016, 09:28 PM
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Start with the tyres rear bar and geo and post your finding. I'm sure they will be a massive improvement.
Old 22 February 2016, 09:32 PM
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Nankang ns-2rs or federal 595rs?

If nankang the road or track ones?
Old 22 February 2016, 09:43 PM
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Never used any of them, but Nankang NS2R have had some good reviews on here.
Old 23 February 2016, 12:34 AM
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Originally Posted by InTurbo
I would try something like the following, one and half degrees up front and a degree in the rear.

(In degrees and minutes )

Front camber -1.30
Front toe 0.00
Total 0.00

Rear camber -1.00
Rear toe in 0.03
Total 0.06

Thrust angle 0.00

Rear bar set on medium to start off with to see how you get on.

Darren
Good start point above

Thrust angle? Do you mean rake?

Also worth playing with tyre pressures and damper setting
If you do it at the track and make adjustments between runs then you will get a feel for what does what and then build on that
Old 23 February 2016, 06:11 AM
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You're p!ssing in the wind until you get some decent rubber on. Then get yourself over onto 22b and ask the question over there, when you get your answers on what other bits you need to buy, then you need to get the car over to glen at Carnetics in melton mowbray to set it all up for you, otherwise you'll just end up going around in circles.

Do it right, do it once.

You also need to do a bit more reading and learn the various terminology and what it all means, then people will know what you're talking about and you'll know what they are talking about.

Last edited by ditchmyster; 23 February 2016 at 06:16 AM.
Old 23 February 2016, 08:21 AM
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Originally Posted by tom-r33
Thrust angle? Do you mean rake?
Thrust angle means how equal the rear toe is in relation to the vehicles centre line. On a 4 wheel alignment this should be 0.00 before any adjustment to the front are made!
Old 23 February 2016, 06:19 PM
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Originally Posted by InTurbo
Thrust angle means how equal the rear toe is in relation to the vehicles centre line. On a 4 wheel alignment this should be 0.00 before any adjustment to the front are made!
Ah right, wasn't familiar with the term, thanks
Old 25 February 2016, 07:27 AM
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if i replace both anti roll bars for a 24mm rear and 22mm front will this cancel out the benfits of just putting a 22mm rear on with my original 19mm front arb or will it be the same difference and make the car feel more planted or will it make it worse than what it is now?

cant help but think in the wet it will be even more hopeless but in the dry with that setup it should corner like its on rails
Old 25 February 2016, 09:35 AM
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Originally Posted by d.kenny
if i replace both anti roll bars for a 24mm rear and 22mm front will this cancel out the benfits of just putting a 22mm rear on with my original 19mm front arb or will it be the same difference and make the car feel more planted or will it make it worse than what it is now?

cant help but think in the wet it will be even more hopeless but in the dry with that setup it should corner like its on rails
did you not listen to what you were told before. thickening up both arb's will cancel the turn in effect out. just stick with a thicker rear arb, get some decent tyres and test it out !
Old 25 February 2016, 09:40 AM
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Calm down mate!

I have seen some forsale and thats what they are!

Or if i buy just the rear will that be too stiff??

Them sizes are what are available that is all...if they are unlikely to suit my needs i will keep searching or just buy a 22mm rear on its own

I was after some advice on the effects of stiffening up everything and kind of guessed that it may be overkill!
Old 25 February 2016, 10:04 AM
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Originally Posted by d.kenny
Calm down mate!

I have seen some forsale and thats what they are!

Or if i buy just the rear will that be too stiff??

Them sizes are what are available that is all...if they are unlikely to suit my needs i will keep searching or just buy a 22mm rear on its own

I was after some advice on the effects of stiffening up everything and kind of guessed that it may be overkill!
I'm not having a go sorry! I'm just saying people have repeated themselves to you!
Old 25 February 2016, 01:14 PM
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If you increased the size of both bars by equal amounts over the oem bar rate the oversteer/understeer balance would remain the same.

If you fitted a 22 front and a 24 rear for example you would have a set up similar to oem front 22 rear.
But you should always use the smallest bar you can, having overly stiff roll bars will reduce suspension independence, make the limit of grip more sudden, reduce your wet grip, and make the car more sensitive to bumps.


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