Castor and springs

[BabyGodzillaGTi-R]

Hey guys actually what does castor really do?
To my understanding it is moving the front kingpin inclination.

Anyway how do u go about to dial in more castor on the R?
I believe one option is the Whiteline kit but what is it really?
A lower arm ecentric bush? Is it adjustable btw?
Dont shoot me i've never seen it b4.

Any other way of dailing in more castor? Does installing a pillow mount give u the facility of dialing in more castor? What would be a better option to dail in more castor?

Another thing, do u guys know what is the standard spring rate on the car.
A friend recommend i should try upgrading to 400lb/ft linear rate and 150lb/ft variable rate. What do u think. Btw how do u convert that to kg/mm. Not familiar with imperial.
Cheers

 

[Sirnixalot]

Castor

Castor is quite important for steering feedback and self centring, the reason that castor affects steering so much is that castor (king pin inclination) causes the swivel plane of the front hub to vary from the vertical as the hub rotates, this has the effect of raising the car slightly, negative castor i.e. king pin inclined back at the top causes the car to rise upwards as the hubs are rotated from the straight ahead position. This gives steering 'feel' and a strong tendency toward self-centring, with the weight of the car itself providing the self centring effect, excessive castor will make the steering very heavy as it will tend to raise the car more. Positive castor has the opposite effect, self centring is lost, the steering becomes light and 'wandery'.

http://www.geocities.com/MotorCity/9526/tca.gif

In order to find the kilograms of pound spring you need to do the following:

400 (lbs in an inch) / 25.4 (mm in an inch) = 15.74 (lbs in a millimeter)

15.74 (lbs in a mm) x .451 (kilograms in a pound) = 7.1 (kilograms in a millimeter)

That spring you listed is a progressive 1.77kg/mm - 7kg/mm spring

 

[Fast Guy]

Sirnixalot, does the bumpsteer kit change the castor or does it do something different?

 

[Sirnixalot]

it bumps the steer! honestly i have no idea....i copied the above from a website. Best bet would be to call Power Station and ask

 

[BabyGodzillaGTi-R]

Very well explained.
Thanks a big lot. Enlightened this fool under the coconut shell. Oh pardon me but my geography sucks. Where is the Cayman Islands located?
:lol:

So if 150lb/ft would roughly equates to 2.7kg/mm, do u find the bias abit too excessive?

 

[Sirnixalot]

that spring rate isnt excessive.

7kg/mm+ is excessive

the Cayman Islands is between Cuba and Jamaica....or around 500miles south of florida