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Front suspension geometry ( race car )
Posted: Sun Dec 03, 2006 7:09 pm
by ALGIK
Anybody have any info on the geometry the race cars run
camber caster toe etc etc
If its top secret you can pm me it will be kept under my hat
Im on a mission and want to really give the car a proper run on the 29th at donno Absolutley full power as there is going to be some fast cars there
Thanks D
Posted: Sun Dec 03, 2006 9:21 pm
by Dollyboy
ask the jedi master m8, his car seems to kick ass most of the time he runs it, however you have over 3 times the hp, bigger wider wheels, possibly different weight distribtion etc so not sure comparing to a standard dolly is all that relevant, although may get you somewhere near...
Posted: Sun Dec 03, 2006 9:37 pm
by ALGIK
Dollyboy wrote:ask the jedi master m8, his car seems to kick ass most of the time he runs it, however you have over 3 times the hp, bigger wider wheels, possibly different weight distribtion etc so not sure comparing to a standard dolly is all that relevant, although may get you somewhere near...
Hope he

some to me

Front Suspension Setting
Posted: Mon Dec 04, 2006 1:01 am
by SPRINTPARTS
As was stated above, front suspension settings can be very dependant on track conditions, spring rates, shock settings and most definitely what tyres you are using.
As a starting point we use around 3.5 to 4 degress negative camber, castor is similar. Tow in 2mm. As already stated it is personal taste etc. We have are swapping from running Yokohma A032R to A048 for next race season, an thinking of increasing the front spring rate by around 25-30% (500lb +) to get the tyres to "work' better.
Mark
Posted: Mon Dec 04, 2006 2:36 am
by SprintV8
Re: Front Suspension Setting
Posted: Mon Dec 04, 2006 8:29 pm
by ALGIK
SPRINTPARTS wrote:As was stated above, front suspension settings can be very dependant on track conditions, spring rates, shock settings and most definitely what tyres you are using.
As a starting point we use around 3.5 to 4 degress negative camber, castor is similar. Tow in 2mm. As already stated it is personal taste etc. We have are swapping from running Yokohma A032R to A048 for next race season, an thinking of increasing the front spring rate by around 25-30% (500lb +) to get the tyres to "work' better.
Mark
Mark im running 500lb front springs
and its 1inch lower than standered at front
Im currently running 225 45 16 dunlop dz02g tyres at the front and 265 45 16 rears 350 lb rear springs
Im going to try your settings and see how it performs
I have been experiancing bad understeer i think the rear tyres are just too big
im going to up the rear tyre press a bit and drop the front a couple of pounds,
I just dont have enough time on track to set it up as i only do the odd track day
I usually hold everyone up on the corners and use the power i have to out drag everyone on the straights

Re: Front Suspension Setting
Posted: Mon Dec 04, 2006 10:31 pm
by DavePoth
ALGIK wrote:
and its 1inch lower than standered at front
I vaguely remember a conversation on autocrossing on the old forum where it was suggested that lowering the back relative to the front would help some with turn in. It just doesn't look quite as cool.

Posted: Mon Dec 04, 2006 10:56 pm
by smifter
Try running it on a soft damper setting at the rear too - I managed to lap Colerne 2 seconds quicker going from full hard to full soft on the shocks.
Or stick a couple of bags of sand in the boot!
Suspension Set up
Posted: Tue Dec 05, 2006 10:53 am
by SPRINTPARTS
ALG1K, I would have thought that with the horespower that you have power over steer would have been the problem.
I have been chasing a chronic oversteer problem , with nothing like the horsepower that you have. The decision to be made, was the front to soft (400lb springs) or the rear to hard (200lb). After a bit of a rethink, the rear suspension was returned to standard, ie all rear arms connected and and panhard rod that was fitted was removed and throw in the bin. Rear shocks (GAZ) were reset slightly firmer and the I acheived about .5 second improvement in lap times. (1m 13sec lap).
With the change of tyres for next year I intend to try stiffer front spring to start with and take it from there. If you still have under steer it might be worth trying softer front springs. When our cars use to use slick tyres (cross-ply construction) front spring ranged from 500-650lb and rear 300-350lb depending on track surface.
It is interesting that many people, us included, will spend much time and money on trying to get more horsepower, when quiet often for a lot less money the car can be made to handle better and improve the lap times.
Re: Suspension Set up
Posted: Tue Dec 05, 2006 5:16 pm
by ALGIK
SPRINTPARTS wrote:ALG1K, I would have thought that with the horespower that you have power over steer would have been the problem.
I have been chasing a chronic oversteer problem , with nothing like the horsepower that you have. The decision to be made, was the front to soft (400lb springs) or the rear to hard (200lb). After a bit of a rethink, the rear suspension was returned to standard, ie all rear arms connected and and panhard rod that was fitted was removed and throw in the bin. Rear shocks (GAZ) were reset slightly firmer and the I acheived about .5 second improvement in lap times. (1m 13sec lap).
With the change of tyres for next year I intend to try stiffer front spring to start with and take it from there. If you still have under steer it might be worth trying softer front springs. When our cars use to use slick tyres (cross-ply construction) front spring ranged from 500-650lb and rear 300-350lb depending on track surface.
It is interesting that many people, us included, will spend much time and money on trying to get more horsepower, when quiet often for a lot less money the car can be made to handle better and improve the lap times.
I can promote oversteer at a prod of the throttle
Its nice to go into a corner on a trailing throttle and sqirt out
Its just at the moment im getting understeer
Its only happend since i changed the ride height and a couple of settings
Im also running diff tyres
I will try your set up and if its a no no i will try my old set up
I didnt want to go back to it as i wanted a higher ride height
Here is a pick of the ride height and the spoiler has been dropped 1" with a spacer

As you can see its quite high and this is how it raced last week.
Settings
Posted: Tue Dec 05, 2006 7:07 pm
by 80Sprint
I don't profess to be an expert on this subject but i think it is good practice to only change one thing at a time. Otherwise if it does not work properly you have trouble working out what to change next or what part of the change you need to put back as it was.
Mike
Posted: Tue Dec 05, 2006 10:24 pm
by xvivalve
i think it is good practice to only change one thing at a time
Wise words Mike...but a bit late for Darren I think!
