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/Lexu...rQ5fTruckQ5fPartsQ5fAccessories#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-...ptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

 

[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/pages/specifications/MA70GA/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-Control-Arms-IMCA-Modifieds,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!

 

[mecevans]

Lorddigital,

I have tien super street coilovers. Would it be worth it to get them revalved? They have 16/9 springs now but its to stiff and it bounces around on slight bumps. Im thinking softer spring and a bigger swaybar. I mostly do mountian driving and autocross. My specs are in third post.

 

[josbeat]

spiller- you car looks good anyway
thats right , shorter sway bar end links, the ST are medium-hard
most of my suspension component was bought many years ago with out thinking on a race Supra.
In the FIA book I saw an extension limiter for the suspension and I have no idea what is the use but maybe Toyota made it to keep the dampers safe over the jumps ehh?
2,5 º will be good for slicks but maybe the problem to get it is to maintain the caster with the stock arms.

 

[LordDigital]

Lorddigital,

I have tien super street coilovers. Would it be worth it to get them revalved? They have 16/9 springs now but its to stiff and it bounces around on slight bumps. Im thinking softer spring and a bigger swaybar. I mostly do mountian driving and autocross. My specs are in third post.

My guess is that by the time you are done changing springs and re-valving the Tein(s) you would spend more money than getting a custom valved coilovers from Wiisass...

 

[josbeat]

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!

yes 1300 kg with a 20 ltr of fuel and no driver but with slicks tyres and of course fire extiguirse , rool cage, two buquets.....but also carbon driveshaft, racing sequential gearbox, lightened doble disk clutch , no mecanical parking brake (hydraulic), small 45 amp battery, woodward stereeng column....and secret doors jeje

1200 kg!!! wow! I now that Supra (BASTOS Supra racing car jeje)

I was looking the RA before I bought the Flex but it was for a strett use so I bought the Flex, now I am looking desesperatte for a second hand RAs jejeje

I have moved earth and skay for those JIC upper arms with out lucky

I have Polly bushing all around , also with an special system to grasse it without removing the arms.

I need to to weight the corners but I like the idea of a custom made dampers

what spring rate will be good for my Supra (1300 kg )? because I dont think it needs a higest rates eh??
12-8 looks soft at the front or good for driffting NO? let me comment my impressios or what I am feeling
the weight at the back is somenting like a 595 kg so there no need much more harder spring than now I have (6 kg) but at the front yes , now I allways have the front setting harder than the rear so at the front if a have now a 12 kg spring i am thinking like a 16-8 will be right for me, yes I think!

I will scan the FIA book and I will send you it by email if you want because my internet connetion is not to fast jejee and not a lot of free time in my life jejejaja.
OK? and you can put it here in the forum.

the engine is powerfull and I just ordered a set of Ls2 coils to hold more boost (problems now over 1,7 bar)
but you ca not imagine how fast it is now with a geabox who chage gears without lossing boost but that is changing up because I can change down 5 gears in less than 2 seconds jejeje

good! , good! that thread is going well

thanks to everybody to read and reaply.
regards

 

[josbeat]

send me your email by PM Lordigital , will try to scan the FIA book this weekend

 

[josbeat]

Tein Flex
full hard
they works great with full poly bushing kit
but a little soft with big slicks tyres

http://www.youtube.com/watch?v=zdPpA8AwqD4

 

[LordDigital]

yes 1300 kg with a 20 ltr of fuel and no driver but with slicks tyres and of course fire extiguirse , rool cage, two buquets.....but also carbon driveshaft, racing sequential gearbox, lightened doble dick clutch , no mecanical parking brake (hydraulic), small 45 amp battery, woodward stereeng column....and secret doors jeje

1200 kg!!! wow! I now that Supra (BASTOS Supra racing car jeje)

I was looking the RA before I bought the Flex but it was for a strett use so I bought the Flex, now I am looking desesperatte for a second hand RAs jejeje

I have moved earth and skay for those JIC upper arms with out lucky

I have Polly bushing all around , also with an special system to grasse it without removing the arms.

I need to to weight the corners but I like the idea of a custom made dampers

what spring rate will be good for my Supra (1300 kg )? because I dont think it needs a higest rates eh??
12-8 looks soft at the front or good for driffting NO? let me comment my impressios or what I am feeling
the weight at the back is somenting like a 595 kg so there no need much more harder spring than now I have (6 kg) but at the front yes , now I allways have the front setting harder than the rear so at the front if a have now a 12 kg spring i am thinking like a 16-8 will be right for me, yes I think!

I will scan the FIA book and I will send you it by email if you want because my internet connetion is not to fast jejee and not a lot of free time in my life jejejaja.
OK? and you can put it here in the forum.

the engine is powerfull and I just ordered a set of Ls2 coils to hold more boost (problems now over 1,7 bar)
but you ca not imagine how fast it is now with a geabox who chage gears without lossing boost but that is changing up because I can change down 5 gears in less than 2 seconds jejeje

good! , good! that thread is going well

thanks to everybody to read and reaply.
regards

“Secret Doors” lol – can’t be more secret(ly) than mine

Keep in mind that Bastos Supra was a DTM competition car ,thus it was N/A. Their weight reduction was EXTREME ,angle grinder and carbon were their gods! The legend says that Toyota supplied the European racing supras (Including SPA ,DTM ,and the British Touring) with 10 MAGNESIUM dog box gearboxes ,and that was it for the “factory support”… All that they had was the low weight and the double wishbone advantage over the M3 and Mercedes Benz EVOs.

BTW I had pictures of the Bastos car and their implementation of the adjustable Upper Control Arms was similar to JIC ,I remember seeing 4 bolts for adjustment ,they defenetly needed the ability to adjust their cars according to the track and weather conditions quick. You probably won’t be able to find JIC arms and will end up fabricating some ,if I were you I would stay away from the European madness called "uni-balls" (aka heim joints) – these on UPA will be brutal for any shape and form of street use… Alternatively if you are not too concerned with the ease of on the fly adjustment you can fabricate custom LCA ,someone else with track MA70 choose to do this and this.
There is a benefit of using custom LCA as opposite to UCA ,mostly the fact that you will get TRUE infinite caster adjustability. With my double adjustable UCA it was ALWAYS very very difficult to adjust castor. To be even more precise bu having adjustable LCA vs UCA ,every time you want more camber you can induce (increase) front track of the car.

On the front and rear track subjects ,I noticed that you use rims with super high OffSet ,this means that you further reduce the already relatively low front and rear track of the car. I have a group B mechanic that always told me that the "magic number" is 1.6. This is because he used to work on 205 turbo T16 where this was achievable... but anyways back to earth - the Length to wheelbase ratio on MK3 and MK4 is not great to begin with because Toyota had no choice but to build market competitive 2+2 GT car. IIRC we are close to 1.8! Ideally it should be between 1.6 and 1.7. BMW M3 GTR and Carrera GT are 2 cars that I recall from memory with r=1.700 ,Prof. Engineer Dr Piech ordered Bugatti Veyron to be with r=1.6 and it is. In other words we want to INCREASE the front and rear track of our cars to help them steer better. That is why my wedsport racing rims are with ET of 22.

On the rims subject to get slick tires of 275 or greater with the larger ET I would also guess that your car can never be lowered as much as mine which is another disadvantage...

You say poly bushings ,but what about the front and rear subFrame spacers?

On the springs ,the 12-8 was on my Tein RA - my buddy club are valved with 18/10 (kg). That works perfect for me ,BUT my car is at least 50 kilos heavier than yours. Springs are important ,but damper valving is the king of a good suspension. I had Tein RA for 2 years and they were good ,but Buddy Club valving feels even better.

P.S. Looking and your build thread I realized that you spend 7500 euros ($11 000) on a great dog box sequential tyranny and you mated this to an engine that has a factory "ping-ball size" whole in the engine block :aigo::aigo::aigo:

 

[josbeat]

Lord
the wheels are 10"x18" ET40 front and 11"x18" ET35 (with the spacer adapters) and I can tell you that my car can be full lowered with out rubbing problems but due a soft spring they are touching the top of the fenders but only the top and only at the front.
and I know that the 660 slick diameter is not the ideal (stock diameter is 624) but on a second hand slicks is what i can get
I tryed to fit the biggers rims I can with the standar rolled fenders (homologation limits)
I was thinking that the wheel track is bigger now than the standar from factory.... i will see

NO at the moment standar subframe bushings
can you tell me the avantages???

with a harder spring rates ,it will be lowered more than now but taking care of the roll center point and the speed bumps height here in Spain , here in my town the town hall tourned mad puting a lot of speed bumps on all streets !!!!

yes it is thruth , our wheel base is not the ideal and like you say we need to get as big wheel tack as possible.
But on my last track day test my supra was as fast on low speed corner as low wheel base race cars (TRACK EVO and CLIO CUP CARS) and was fasted on a hig speed corners so i am happy , like a told you , i want to eliminate a little bit the body roll and a 2.5º negatie camber plus my powerfull engine and plus the dog box 6 speeds wowwww!!! IT can be a fast car! jejeje

I tried to eliminate the standar track diferences , so now a line i the middle of the tyres is the same front and back, I had no information about what is the best wheel track and I was suppousing that the oversteer problems came by that track difference... I have room to play anyway.

now I am talking with a companny who can make a custom made coilovers with a separate rebound and compression adjustment, the last thing is the spring rate choice.
but reading your comments about yours dampers.... if you say those are mutch better than the RAs I will consider that option.

I want to show you some ideas I have to get the car lowered with out loose the roll center point or almost get the supra very low maintaining the suspension arm angels as better as possibe.

uhmm I`ve seen those custom lower arms before in other forum.... I just started with my proyect after see that thread and also I took some ideas like the woodward stering column but I prefer to move the camber at the top because it dosnt change the track and also it will no need to adjust the toe a lot.
I like to have the possibility of adjust everything at the track.
wait till I send you the FIA book where are all the different suspension arms toyota made.
with 2.5º-3º of neative camber will be sufficient for me and with the double wishbonne also ....yes??? it is what Dunlop and Toyo recomend for theirs race tyres

yes my doors are a carbon fibre door set from Japan they only weight 2,5 kg each but I still have the electric windows lifters and the stock heavy mirrors. (seeking a companny who can make a mirros plates in carbon to fit a F1 style carbon mirrors)
if in the furture I use the car only at the tracks , my plan is to get a set of plexi glass fron Japan (rear, doors and sides) no windows lifters , bigger custom made carbon fenders DTM style front and rear (I have a friend who can make it here sheap) set the engine at lower possition than now , front lip and cannards, rear carbon hatch, no front beams and the electric motors.... and maybe it will be close to 1250 kg. ehh?

Lord at the video threads I posted a video where you can see the gearbox in action.
soon a thread on how to fit the Quaife gearbox on our Supras.
soon a thread on how to get the 7mgte coldest than ever


P.D. I wannna see your Bastos photos if is possible jeje

I have that photo of the TRD oficial fujitsu supra

 

[josbeat]

look at that!
http://forums.lorddigital.com/Project/Race MA70 Pics/
so those racing photos are yours!! I have no idea!
I had it on my favourite sites list many years ago jeje
i have more race supras photos and videos if you like it.

 

[josbeat]

here some pictures
one with the suspension parts position modified , lower ball joint moved and the upper arm turned over and moved from left to right and viceversa.
it is an idea on how to get the roll center back to normal on a lowered supras.

other where we can see the front and the rears wheels with almost the same camber

the last is what i want to have my supra like a moderm DTM jejeje