55EXX
27-11-2008, 09:37 PM
Disclaimer: The following is provided as a GUIDE ONLY, and neither myself nor Ozhonda take any responsibility for the outcomes of someone else doing the following. You follow these steps at your own risk!
Aim:
To increase caster angle
Required:
To swap upper control arms - basic tools
To install caster kit - professional intall recommended as a bolt needs to be pressed out and whiteline's KCA301 kit
Swap of control arms
Steps:
This was a pretty straight forward swap. First i jacked the front of the car up and sat it up on stands. removed the wheels and undid the lock pin through the castle nut on the upper ball joint. then i undid the 2 bolts in the engine bay for the other side of the upper control arm to be free. then i also had to unbolt the top of the struts. i dropped the strut down. you might be able to manouver it out from there but i had also undo the bottom strut bolt for it to drop down far enough. be careful here cos the brake line is bolted onto the shock body and it would be wise to undo this also to save pulling the brake line. it came out easy. i reinstalled onto the other side of the car. repeat etc
First driving impression with this done with no corrected wheel alignment was impressive. it was only slightly harder to turn at lower speeds and had a more forceful pull to centre. the squeel from the wheel as i understeered was a deep howl instead of the usual schreech. i never really had a chance to test higher speed cornering but lower speed ones it slighty improved or it may be the harder pull to centre making it feel faster. the wheel alignment would have also been out, contributing to biased results.
Install of Whiteline caster kit (shims)
Steps:
Follow fitting instuctions given by whiteline KCA301 (http://www.whiteline.com.au/docs/instructs/158_KCA301.pdf)
i tried this DIY and captive bolt B (outer) i could not get out! the instructions say press out. i tried hitting it with a hammer, got a vice onto it and to no avail. i had to file the bolt's burred edge down and bolt it back together for pros to do. this is recommeded.
i had them install all 3 inner and 8 outer washers for a total caster increase of 2.5 degrees.
at my last wheel alignment my caster angle was
RHS +0.52 LHS -0.07 difference right to left .59
this time around my caster angle is now
RHS +5.37 LHS +4.65 difference right to left .72
when intalling this kit it caused one of my old bushes to fail. the inner lower control arm bush is shot from the control arm being pushed forward hence the higher caster value for this right hand side.
i would definately recommend inspecting this bush prior to fitting this kit. it puts it on a quite a harsh lookng angle and will be replacing it with oem rubber ones as i don't think poly bushes would surrvive being squished like it is and would force out its lubrication.
with this shot bush i continue the wheel alignment to 0 toe front and 1mm total rear. this is what i have used and been happy with in the past. i might also note that the camber angles front are ~2.2 and rear ~1.9. this is unadjusted from lowering my car.
so total gain in castor taken from LHS only (bush still ok) is 4.72 degrees! so the kit is said to give an increase of 2.5 so the swapping of the control arms should yeild a gain of ~2.2 degrees alone.
the kca301 kit consisted of shims and high tensile bolts my only concern with its design it that the shims are flat and not wedge shaped therefore more compression would be put on the inner edges of the shims. otherwise it is a very straight forward kit. some are also concerned about the moving of the geometry causing more bump steer. i have yet to experience it.
Driving impression.
again it had a stronger pull to center and my car felt more point and shoot. quick tugs on the wheel would see the car stay true to that line and dart over. it seems alot harder to get the car to understeer and when it does it also has the deeper howl.
it does tho feel strange. i am too used to going around a higher speed corners and being held back by the front understeering this time round i felt more cautious as the speeds were the same but the evident screech was not there. i was able to push it abit harder. only slightly before the howl kicked in.
highway straights it feels solid. like its not going to wander on the road.
i have yet to experience any bad bump steer and will post if i do.
the car has a more sportier feel.
Other comments:
for the little money spent this is a good mod.
the simple swapping of upper control arm for a 2 degree gain in caster for the cost of a wheel alignment is awesome.
i will be replacing both inner control arm bushes and getting the caster evened out by taking a shims off the RHS to take it down to within .3 degrees of the other side.
Aim:
To increase caster angle
Required:
To swap upper control arms - basic tools
To install caster kit - professional intall recommended as a bolt needs to be pressed out and whiteline's KCA301 kit
Swap of control arms
Steps:
This was a pretty straight forward swap. First i jacked the front of the car up and sat it up on stands. removed the wheels and undid the lock pin through the castle nut on the upper ball joint. then i undid the 2 bolts in the engine bay for the other side of the upper control arm to be free. then i also had to unbolt the top of the struts. i dropped the strut down. you might be able to manouver it out from there but i had also undo the bottom strut bolt for it to drop down far enough. be careful here cos the brake line is bolted onto the shock body and it would be wise to undo this also to save pulling the brake line. it came out easy. i reinstalled onto the other side of the car. repeat etc
First driving impression with this done with no corrected wheel alignment was impressive. it was only slightly harder to turn at lower speeds and had a more forceful pull to centre. the squeel from the wheel as i understeered was a deep howl instead of the usual schreech. i never really had a chance to test higher speed cornering but lower speed ones it slighty improved or it may be the harder pull to centre making it feel faster. the wheel alignment would have also been out, contributing to biased results.
Install of Whiteline caster kit (shims)
Steps:
Follow fitting instuctions given by whiteline KCA301 (http://www.whiteline.com.au/docs/instructs/158_KCA301.pdf)
i tried this DIY and captive bolt B (outer) i could not get out! the instructions say press out. i tried hitting it with a hammer, got a vice onto it and to no avail. i had to file the bolt's burred edge down and bolt it back together for pros to do. this is recommeded.
i had them install all 3 inner and 8 outer washers for a total caster increase of 2.5 degrees.
at my last wheel alignment my caster angle was
RHS +0.52 LHS -0.07 difference right to left .59
this time around my caster angle is now
RHS +5.37 LHS +4.65 difference right to left .72
when intalling this kit it caused one of my old bushes to fail. the inner lower control arm bush is shot from the control arm being pushed forward hence the higher caster value for this right hand side.
i would definately recommend inspecting this bush prior to fitting this kit. it puts it on a quite a harsh lookng angle and will be replacing it with oem rubber ones as i don't think poly bushes would surrvive being squished like it is and would force out its lubrication.
with this shot bush i continue the wheel alignment to 0 toe front and 1mm total rear. this is what i have used and been happy with in the past. i might also note that the camber angles front are ~2.2 and rear ~1.9. this is unadjusted from lowering my car.
so total gain in castor taken from LHS only (bush still ok) is 4.72 degrees! so the kit is said to give an increase of 2.5 so the swapping of the control arms should yeild a gain of ~2.2 degrees alone.
the kca301 kit consisted of shims and high tensile bolts my only concern with its design it that the shims are flat and not wedge shaped therefore more compression would be put on the inner edges of the shims. otherwise it is a very straight forward kit. some are also concerned about the moving of the geometry causing more bump steer. i have yet to experience it.
Driving impression.
again it had a stronger pull to center and my car felt more point and shoot. quick tugs on the wheel would see the car stay true to that line and dart over. it seems alot harder to get the car to understeer and when it does it also has the deeper howl.
it does tho feel strange. i am too used to going around a higher speed corners and being held back by the front understeering this time round i felt more cautious as the speeds were the same but the evident screech was not there. i was able to push it abit harder. only slightly before the howl kicked in.
highway straights it feels solid. like its not going to wander on the road.
i have yet to experience any bad bump steer and will post if i do.
the car has a more sportier feel.
Other comments:
for the little money spent this is a good mod.
the simple swapping of upper control arm for a 2 degree gain in caster for the cost of a wheel alignment is awesome.
i will be replacing both inner control arm bushes and getting the caster evened out by taking a shims off the RHS to take it down to within .3 degrees of the other side.