need help for track use

[josbeat]

Hi! I am building a track supra and here is the details of my suspension

ST sway bars
Tein Flex with edfc
1300 kg
A1 rear camber links
0,5 negative camber rear
1 negative camber front (I am seeking for 2,5)
10" 265/660 18 front wheels
11" 285/660 18 rear
megan racing outher rods

I want to eliminate the left rigt movements and gets more negative camber at the front
what happens with the saway bar on a lowered cars... it works well or i need to adjust the sway bar end lengh to get the standar possition?

I am happy on how the tein flex works but maybe it needs a higer spring rates??
or ajusting the spring preload will help?
Now I have the tein spring preload adjusted harder than Tein recomend for street use
and on a closed track I am using the harder hydraulic setting (0 on the EDFC controler)
but looks soft with the slick tyres

please help me to get a good set up for closed tracks.

see the picture

Shot at 2011-06-19

[josbeat]

too mutch roll

I am trying to get the sizes of those braces

http://cgi.ebay.com/ebaymotors/Lexus...#ht_1604wt_772

if anyone can get it....?

basically I , like a lot of supra mk3 owners,,,are looking on how to adjust the front camber more than 1º

other possibility is that
an ajustable ball joint but..... toyota and lexus have the same pattern ?

http://cgi.ebay.com/ebaymotors/SPC-f...Q5fAccessories

[mecevans]

Biggest improvement for me was getting rid of all the slop.

New rack non-pps
Ball joints
Energy suspension bushings
Tie rods

As of now my alignment is

Camber F -1.6 R -1
caster 7.1
Total Toe F .01 R .30

0-50 mph it feels great but higher speeds it feels numb and heavy. Right now i have a stiff springs and soft sway setup but i would preffer the opposite. I dont know the drop my tien ss give me but from the wheels center to fender is 13 1/2 in. I can get 2+ degrees of negitive camber.

[josbeat]

Biggest improvement for me was getting rid of all the slop.

New rack non-pps
Ball joints
Energy suspension bushings
Tie rods

As of now my alignment is

Camber F -1.6 R -1
caster 7.1
Total Toe F .01 R .30

0-50 mph it feels great but higher speeds it feels numb and heavy. Right now i have a stiff springs and soft sway setup but i would preffer the opposite. I dont know the drop my tien ss give me but from the wheels center to fender is 13 1/2 in. I can get 2+ degrees of negitive camber.

how can you get 2º of negative at the front?

now I have soft spring F12 R6 and harder sway bar bt at the back I am still using the softed possition on the sway bar adjuster.

like I lightened my supra to 2700 lbr those springs aren`t to bad but adjusting the preload and sortening the lengh of the damper

my principal problems are

my front tyres touch the top of the fenders on a really hard corners when running with a pasenger (closed track only )
and the steering is not very stable on a straigh line over bummpers so that way I am thinking like the sway bars are under pression.
uhmm maybe?
soon I will post a onboard video to show what I am saying

[Van]

Hola!
I was just thinking this suspension problem might get more attention if it were moved into your build thread. I found a lot more help for my build by keeping all the problems in there.
Having said that, TRD made adjustments to their Supra suspension for Group A racing, so I know it can be done; here is a link for example: http://www.turbosupras.com/pages/pag...0GA/ma70ga.htm . You may need to contact some of our Supra fabricators here on Supramania, to see what they suggest; such as Wes Beech, who has developed a set of rear suspension arms. Van

[josbeat]

Hello Van
uhmm it is not really a problem with my building race car with its very close to be fynished , rather it is a thread to see with is the best suspension set-up out there for racing use.
I am sure here in Supramania a lot of supra owners have more experience than me.

I know that web page many years ago thank anyway but I have a FIA book with all parts made by TRD when they was racing , I had to have that book to homologate my car like a race car here in Spain, most of the parts are not exactly the same (age) like the brakes (mines are wilwood) but on that book it looks almost the same so I havent had any problem on the government inspections.
but about the suspension braces..... they made a lot of diferent arms, for rally use , track, diferent set ups ... a lot! but there in the book only comes with the photos not the sizes or specifications .
for example , it have a lot of diifferent hubs and a lot of mono nut wheel attachments but it is not for sale more, so how to get a lower supra with the a good roll center on this times??
I will talk with Beech to see what he say

thanks

[supraguru05]

This is very simple for us in the USA, I am not sure of part availability where you are. The easiest/cheapest albeit not necessarily best solution is to shorten the factory arms and reweld the cast aluminum together with some bracing. The other option is to use a removable ball joint off of another car and make your own tubular A arms. Here are some examples. This is the best help I can provide. If you are not a fabricator then you need to find a race shop to do this for you. It shouldn't be hard or expensive.

http://www.speedwaymotors.com/Upper-...eds,29430.html

[josbeat]

thanks Supraguru
I been looking those tubular arms before but I will try with the ajustable ball joint, I like to adjust the camber easy and fast when arrive at the circuit and back to normal when living the circuit by the public roads.
I will report of how it going

I am the owner of a big car Garage here in Spain but really i dont like to cut and weld the aluminium arms

my car is going very fast on corners, fastest than Evos and like you can see on the video fastest than the Atom! but it can be more more fast jeje
I got a lot less body roll making the dapers shortes than normal and adjusting the spring preloads to reduce the travel of the dampers on the extension movement

uhmm ... If I adjust the preload all hard till the suspension travel betwing lifting the car on the air and at the floor they dont move more than 3-4 mm like race cars keeping the confort over bumpers of a soft springs eh??? that will be my next text and also I will make a new sway bars end links to reduce any tension
what are you thinking guys??

[spiller]

You want your sway bars to be parallel with the lower control arm roughly. Since the car is lower than factory you'll need a shorter end link. I don't know what the stiffness of the ST sway bars is but your spring rates are probably too soft. Generally softer spring rate = stiffer sway bars but 13/6 might be too soft still. I have 14/12 with whitine swaybars front and rear on middle stiffness setting and body roll isn't too bad but I am going to try going to the hardest setting for my next track day. I have the same issue with the neg camber at the front but I'm going to try a new wheel aligned, I have heard others can easily get 2.5neg at the front with factory upper and lower front arms.

Ps I am going to PM you about your new track wheel specs!

Here is my car's position with the above set up through a couple of corners...



Still too much so I will try the hardest setting next time. With the spring pre-load my coilovers came with a warning stating that adding more than 5mm of preload on the spring would cause damage to the dampers. It advised to add just enough preload to hold the spring captive when completely unloaded. Hence quite a bit of droop at the front with the wheels off the ground.

[LordDigital]

As Guru is suggesting there are 2 options ,cut and weld or build from hot rod arms. There used to be a third option ,with adjustability at the upper control arm ball joint (JIC Magic Adjustable UPC I believe) - but this is not longer available. You may be able to find JIC magic used ,but if you need to have "on the fly" adjustability you can always fabricate. I have no idea why would you need this tough ,I've driven my car 300km to the racetrack with -4.x camber on the streets with no problem and no wear to the tires whatsoever...

My suggestions for you car :

Get rid of the Tein Flex - this is nothing more than ENTRY LEVEL valved dampers ,at the very minimum I would recommend Tein RA valving or better. I run Buddy Club Racing Spec 12/8 kilos ,with additional spring inserts - IMO the best off the shelf dampers for MA70 ,and as any other good suspension mod for these cars - no longer available due to low demand... there is a forum vendor here that can do a custom valving for you based on your car corner weight - also a great idea!

A good valved car would not need a rear sway bar ,IVO told me that you are making 500-600hp? if this is true exit corner traction is much more important … with good dampers I would try to extend the arms of a stiff bar or to downgrade to stock.

Bushings everywhere ,front and rear subFrame spacers too (I would even go with AL spacers there).

Did you do a roll cage already? If you did ,which front extension did you choose BASTOS-Bermani style (DTM) or TRD style (GroupA)?

Are you saying that your car is 1300kilos (with no driver) - this would be equal to 2866 lb which for caged 7m-gte supra seems quite low ,but achievable since BASTOS car was quoted to be 1200 kilos (2645lb)

Is there any way you could scan the FIA parts book ? Or maybe give to Ivo and I will talk to him to get it scanned for the community - this would be very interesting to see!