HQ vaTorana Stub axles
#1
Posted 28 November 2005 - 06:41 PM
I seem to recall the HQ has 2 degrees more but can't remember figures.
M@
#2
Posted 28 November 2005 - 09:35 PM
Torana is 7
HQ is 9
From my memory
Its definatly 7 and 9 but I might have them the wrong way round. Can't find my CRS catalogue
#3 _draglc_
Posted 28 November 2005 - 10:06 PM
#4
Posted 28 November 2005 - 10:30 PM
Dave
#5
Posted 29 November 2005 - 10:03 AM
are drum brake torana any different? I have got a pair lying round somewhere
#6 _fastlx2door_
Posted 02 December 2005 - 12:01 AM
#7
Posted 02 December 2005 - 12:21 AM
sure does
Matt will explain it all I'm sure
#8
Posted 02 December 2005 - 05:04 PM
I at least now know enough how to draw it on autocad and calculate the different characteristics etc now, so I can manually do most of the things I want to check.
Starting to get some good bits together though. I got a nice UC sunbird front end from Torana05 last weekend so that should get things moving having the starting piece to work on.
The King pin inclination effects a few things - the main 2 being:
1. The 2 degree difference from the Torana to the HQ stub will have a small change in the scrub radius of the front wheels which will make the steering 'feel' slightly different. this also depends what wheel offset you run though.
Ideally, you should have no scrub radius as it makes the steering heavier and will cause harsh feedback through the steering wheel when you hit a bump.
The 2 degree difference is not huge but significant.
2. The second thing is when you turn into a corner, the outside wheel on the turn will progressively lose negative camber as you turn the wheel. This is only fairly small (1 degree of camber by the time the wheel is turned at 45 degrees) but given the option, you would choose the stub with the lower KPI.
The other difference is with the Torana upper control arms, it is pretty easy to run out of adjusting shim room in the upper control arm if you use the HQ stubs and want to run lots of Camber and Castor - the torana stubs will allow more adjustment.
M@
#9 _J&S Racing_
Posted 02 December 2005 - 06:34 PM
#10 _slr6000_
Posted 03 December 2005 - 01:18 AM
I want the LX as low as possible and was thinking that using the HQ stubs might help keep the suspension where it should be. Iv noticed the lower you go the more the camber changes. would this be the case?
I would like to get into some drifting so im keen to get the suspension right.
#11 _Herne_
Posted 03 December 2005 - 06:44 AM
Cheers
Herne
#12
Posted 03 December 2005 - 08:44 AM
#13
Posted 03 December 2005 - 03:48 PM
I just wanted to be sure which was 7 degrees and which was 9 degrees before I went and bought the CRS 2" dropped ones. Hence the reason for my original query.
My comments above assume the Torana ones to be 7 degrees and the HQ's to be the 9 degrees which I think is the case.
I have to measure my camber curve on the HQ stubs I am currently using to comment exactly what the camber does through out the range of suspension in degrees but mine certainly seems to actually lose negative camber as the wheels go up through their suspension travel. The Torana and HQ stubs will give you the same actual camber curve through the full range of bump and extension of your suspension (this is determined by the height of the stub axle between upper and lower balljoints) but the car will sit 1" higher in the curve with the HQ stub axles assuming the same ride height or alternatively the car will be 1" lower and operate at the exact same height suspension wise. I would really have to measure them to say which is the better or worse part of the curve to operate in.
The CRS 2" drop will again give the exact same camber curve as the HQ and Torana stub but will let the car sit 2" lower.
As I mentioned above, you will lose an additional 1 degree of negative camber when the wheels are turned 45 degrees with the 9 degees KPI and that is about where full lock would be so for a normal type high speed corner, you are more likely to be turning about 12to 15 degrees so you would only lose 1/4 degree negative camber on that corner.... for a race car, you could compensate this by running an additonal 1/4 degree static negative camber and probably not notice it a lot but for road cars where tons of negative camber kills front tires, this is nice to reduce the amount of camber gained in a corner. The less static camber you run, the better the straight line braking. I hope this setup I am planning will run around about 0.5 to 0.75 degree static negative camber.
I plan to run the 7 degree CRS 2" drop stubs as my setup at this stage unless my measuring etc shows up something unexpected.
The bad effects of the short length of the stub axles is far worse on these cars than the 2 degrees difference in KPI but I am out to capture all the nice options in this front end rebuild.
I am sick of the shit you hear from the Suspension shop 'Experts' who want to sell you the off the shelf item they have in their store hence why I am undertaking this task.
SLR6000, I'd also be looking at that rear end if you are planning some drifting.
Do you have any current plans for the rear?
#14 _Herne_
Posted 03 December 2005 - 03:53 PM
I dont think they were 'just' HQ stubs, the factory did a bit to change the whole setup, not like many owners here who just seem to bolt em on and run.But as Brock and others showed you can still make them handle and negotiate corners pretty well with the HQ heritage stub assembly.
Cheers
Herne
#15
Posted 03 December 2005 - 03:56 PM
1. The Steering rack
2. The upper control arms
3. The steering arms.
If you can find those and put them on your LX, there is no need to change to the UC front.
Depends what you want to achieve at the end and what you actually have on yours now and how much you can get a UC front end for.
I won't be using any of those above even on my UC front end when I am finished.
M@
#16 _CHOPPER_
Posted 03 December 2005 - 08:19 PM
#1 Static ride height, rim offset and overall tyre diameter will all affect scrub radius to an extent.The King pin inclination effects a few things - the main 2 being:
1. The 2 degree difference from the Torana to the HQ stub will have a small change in the scrub radius of the front wheels which will make the steering 'feel' slightly different. this also depends what wheel offset you run though.
Ideally, you should have no scrub radius as it makes the steering heavier and will cause harsh feedback through the steering wheel when you hit a bump.
The 2 degree difference is not huge but significant.
2. The second thing is when you turn into a corner, the outside wheel on the turn will progressively lose negative camber as you turn the wheel. This is only fairly small (1 degree of camber by the time the wheel is turned at 45 degrees) but given the option, you would choose the stub with the lower KPI.
#3 The other difference is with the Torana upper control arms, it is pretty easy to run out of adjusting shim room in the upper control arm if you use the HQ stubs and want to run lots of Camber and Castor - the torana stubs will allow more adjustment.
M@
#2 Increasing the static castor reading will cause a gain in negative camber on the outside wheel during a corner. With a castor angle of zero, theoretically the camber will not alter when the wheels travel from lock to lock. In practice, this doesn't happen. If you increase the static castor to +3 and have the static camber at zero, in theory you will have zero camber in the straight ahead position and you should get a bit of negative camber on the outside wheel as you approach full lock. This may or may not happen, as you get camber change with suspension travel. Suspension travel will happen through a corner whether you are decreasing, maintaining or increasing your vehicle speed. Good thing I remember some of my high school physics.
#3 Just do what I did in my LX, install longer bolts. You can get a standard ride height LX to -4.5 camber without a problem. That's as far as you can go with standard ride height if you want the top bump rubber to stay in place. The other trick needed is to use flat washers instead of shims. Washers can't fall out. Shims do on a regular basis. Used to see it all the time on vehicles where heaps of shims had been installed.
#17 _slr6000_
Posted 04 December 2005 - 01:06 AM
So I�m guessing the uc upper control arms help with with neg camber in a turn? Also read on the old forum about relocating the upper control arm holes but I�m thinking this was done when the HQ stub was used to keep the control arm on the same plain at standard ride height.
Another thing iv done that helps not so much in handling but in road feel is to use a solid type steering knuckle in place of the lower rubber jointed knuckle as well as solid mounting the rack and pinion. It does make a big difference.
I havn't finished the rear end yet still have to mount a sway bar in there and was thinking of a panard rod of some sort. I�m running coil over's that are set inwards from where the springs would normally be so I would think I will have to use a decent size sway bar to keep body roll down.
Looking forward to seeing some pics of what you'v done M@
#18 _Herne_
Posted 04 December 2005 - 08:29 AM
yes I run the solid double knuckle set up, you will either like it or maybe hate it. You certainly feel the car under you.Another thing iv done that helps not so much in handling but in road feel is to use a solid type steering knuckle in place of the lower rubber jointed knuckle as well as solid mounting the rack and pinion. It does make a big difference.
M@
Cheers
Herne
#19 _CHOPPER_
Posted 04 December 2005 - 07:10 PM
#1 The UC upper arms have offset balljoints. This allows more positve castor, which can be achieved with LH/LX upper arms by performing a wheel alignment. In my 21 years in the tyre industry, nobody wanted more than +2 castor, as the steering became too heavy. In my view, there is no point in havng more than +3 castor. If you have power steering or you are built like Swats-his-name, you can get away with it. However, castor jacking becomes a problem when the castor is too high. With XR - XF Falcons, the limit is +3.5 before castor jacking becomes a problem.#1 So I�m guessing the UC upper control arms help with with neg camber in a turn?
#2 Also read on the old forum about relocating the upper control arm holes but I�m thinking this was done when the HQ stub was used to keep the control arm on the same plain at standard ride height.
#2 Lowering the position of the top arms can be done with either set of stub axles.
#20
Posted 20 December 2005 - 06:39 PM
I rang CRS today to get the run down on their stubs.
They reckon the Toranas has 9 degrees KPI and the HQ 7 degrees <_<
Does anyone have anything from GMH to verify what either the Torana or HQ KPI is? as I though they were the other way round for some reason.
The other thing I discovered is the 2" drop HQ stub they do is still 1" lower than their 2" drop torana stub for those wanting the lowest they can possibly go.
Unfortunately, I wanted a stub with 7 dgrees KPI and 2" drop from the Torana height but it appears they do not do one. Aaaahh more investigation needed before I even purchase my stub axles.
M@
Edited by Toranamat69, 20 December 2005 - 06:39 PM.
#21
Posted 21 December 2005 - 07:21 PM
I did a bit of reading today and it seems pretty unanimous that the HQ-HZ has the 7 degree KPI and the torana 9.
Interrestingly the main concern seemed to be that people couldn't remove sufficient shims to get back to a decent camber for the street as you run out of shims to remove with the HQ stubs on torana front ends.
Has anyone else had this drama?
I am currently running this system and have no dramas with that at all. Is this perhaps a case of the old sagging LX crossmembers being responsible not the stub axle?
M@
#22
Posted 21 December 2005 - 08:30 PM
I recall..... in my distant memories that if you remove all the shims your still left with 1 deg neg. Since you probably run alot more than this you never noticed the lack of adjustment
CRS spindles in commy pattern is ideal. As commy brakes bolt straight up
Be careful though with caliper choice. Dave has Brembos on his..... fit fine. Phils trying to put AP's (CP5200) on his and the caliper fouls the tierod end. So new brackets will need to be fabricated to suit
This is on a 330mm commodore disc.
Minor problem...... but still a headache
#23 _CHOPPER_
Posted 22 December 2005 - 08:25 PM
If you have an RTS Torana, there are washers on the studs that account for about 1.5 degrees of camber and a couple of degrees of castor. To remove these, the studs need to be removed. Best way to start that job is to dis-connect the top ball joint from the stub axle. They are added at the factory and would have nearly 30 years of dirt and grime, so they may not be easy to see. I'll see what I can do about a pic.Sag could be an issue
I recall..... in my distant memories that if you remove all the shims your still left with 1 deg neg. Since you probably run alot more than this you never noticed the lack of adjustment
#24 _2wild4u_
Posted 07 February 2006 - 11:43 PM
#25 _Herne_
Posted 07 February 2006 - 11:51 PM
2wild4u I didnt think you could have too much neg camber lol
Cheers
Herne
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