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Unusual Camber Setup? -1.5 Degree Front 0 Degree Rear

Guest qtvinsta

By Guest qtvinsta,
in Suspension, braking, tyres and drivetrain

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Guest qtvinsta

Guest qtvinsta

Posted
Posted (edited)

Hi all,

Now i just got a wheel alignment done and feel the person who did it may have been fibbing... was it a waste of my money?

background:

I drive a r34 gt-t which had tein flex coilovers installed and car lowered roughly an inch and a half. Now after having this setup for over 3 years i've had enough of the rear wheels wearing out on the inside faster. The front wheels seem to wear more evenly though the inside is probably only slightly more worn but not as bad as the rear.

Two week ago I installed a pair of jjr adjustable rear upper arms and on the weekend put 2 new rear tires.

I thought i'd now get the rear wheels adjusted to have less negative camber.... simple enough thought...

I've just taken to this tyre place (they've been good to me in the past, so i won't mention which one) and all i wanted was to reduce the negative camber in the rear... they said i must align the front too, which i agreed too...

In the end, only the front wheels had adjustments made and the rear wheels were untouched... after requesting the rear to be adjusted and getting resistance i gave up... the mechanic said that the rear was perfect the way it was and that if I wanted it adjusted then i need to have install adjustable front camber too to adjust the rear...

Actually i think i just answered my own question... I couldn't make any sense of what the mechanic said (i realised when I was trying to explain it in the paragraph above!)

I'm quite certain it was probably because the mechanic just feed me some BS to get out of doing more work.

Anyways, that's the reason for the topic title... is it unusal to have a bit of negative camber up front and 0 camber or close to it in the rear?

Any comments? Any recommended place where I can get my rear camber adjusted properly? anywhere between Strathfield and Liverpool is fine with me and surrounding suburbs.

Thanks,

Edited by qtvinsta
FineLine Grand Master

FineLine

Posted
Posted

Not at all. quite a reasonable setup for a street car imo. I run around 2.5 degrees on the front and 1 on the rear. (both negative) my car does see trackworkand i couldnt be bothered getting an alignment every time i do it. If it wasnt quite so aggressive i would run heaps more but premature wear on the road deters me from doing it.

Guest qtvinsta

Guest qtvinsta

Posted
Posted

yeah I didn't think so either. No need to have the front and rear matching cambers.

Now that I know, I will be able to argue if this happens again...

Question now is whether or not to bring the car back to the same place to get the rear camber adjusted like I had wanted in the first place.

Also complain to the boss about his lazy mechanic. Hopefully not have to pay a second time for something that should have been done already

Maybe just forget them and take it to a reputable place like pedders.

any other reputable places that have experience with adjusting camber kits ?

Sydneykid Grand Master

Sydneykid

Posted
Posted
Hi all,

Now i just got a wheel alignment done and feel the person who did it may have been fibbing... was it a waste of my money?

background:

I drive a r34 gt-t which had tein flex coilovers installed and car lowered roughly an inch and a half. Now after having this setup for over 3 years i've had enough of the rear wheels wearing out on the inside faster. The front wheels seem to wear more evenly though the inside is probably only slightly more worn but not as bad as the rear.

Two week ago I installed a pair of jjr adjustable rear upper arms and on the weekend put 2 new rear tires.

I thought i'd now get the rear wheels adjusted to have less negative camber.... simple enough thought...

I've just taken to this tyre place (they've been good to me in the past, so i won't mention which one) and all i wanted was to reduce the negative camber in the rear... they said i must align the front too, which i agreed too...

In the end, only the front wheels had adjustments made and the rear wheels were untouched... after requesting the rear to be adjusted and getting resistance i gave up... the mechanic said that the rear was perfect the way it was and that if I wanted it adjusted then i need to have install adjustable front camber too to adjust the rear...

Actually i think i just answered my own question... I couldn't make any sense of what the mechanic said (i realised when I was trying to explain it in the paragraph above!)

I'm quite certain it was probably because the mechanic just feed me some BS to get out of doing more work.

Anyways, that's the reason for the topic title... is it unusal to have a bit of negative camber up front and 0 camber or close to it in the rear?

Any comments? Any recommended place where I can get my rear camber adjusted properly? anywhere between Strathfield and Liverpool is fine with me and surrounding suburbs.

Thanks,

Well lets start with the technical stuff;

1. There is no one single right alignment settings for every R34GTT. It depends on what you do with the car, how you drive it, how much power it has, what other suspension modifications it has, what height it is, what tyres etc etc. A simple example, if you use it on the track then 2.5 degrees of negative camber is probably OK on the rear, but if you drive to work on a freeway every day then around 0.75 degrees is better for tyre wear, but if you use it at the drags then you need around 0.5 degrees positive camber. Without sufficient detail no one can tell you what alignment settings you should use.

2. Without the current alignment settings, no one can tell you which direction to go in adjustments. So what are they?

3. Changing only the rear upper control arms is a not a good solution technically speaking, you should adjust the traction arms in tandem with the upper control arms, otherwise you end up with undesireable bump steer (not that any bump steer is ever desireable in a performance car). Maybe that's what the alignment guy was trying to tell you?

4. "lowered roughly an inch and a half", lowered from what? When they role out of the factory they are 390 mm front and 380 mm (centre of wheel to guard). After 1,000 k's or so they settle at 385/375. After 60,000 k's or so they are usually at 380/370. By that time the standard shocks will be stuffed and if they aren't replaced the springs wear out faster and so the car will drop to around 375/365 fairly quickly. So if you are 1.5" (~40mm) lower then you could be at 340/330, which is actually 50 mm (2") lower than when it was new.

There is only one answer, get the tape measure out and measure the height, centre of wheel to guard on all 4 corners, then you will know for sure what height it is. Then we can help you.

Cheers

Gary

Guest qtvinsta

Guest qtvinsta

Posted
Posted

Straight after the 'camber' arm was fitted, I remember saying to myself that it looked as though toe would change if the camber was adjusted. I'm hoping that I won't need to install more like toe rod and traction rod and remove hicas...

Ultimately, I only wanted to have the vehicle sitting slightly lower to the ground. It's my daily ride so I definitely would appreciate longer tyre life, hence why I thought 0 degree rear camber and only slightly negative front camber

I will measure height and post tomorrow.

Cheers,

Psymon Mentor

Psymon

Posted
Posted
3. Changing only the rear upper control arms is a not a good solution technically speaking, you should adjust the traction arms in tandem with the upper control arms, otherwise you end up with undesireable bump steer (not that any bump steer is ever desireable in a performance car). Maybe that's what the alignment guy was trying to tell you?

Ok this interests me as i have aftermarket rear upper arms but no aftermarket traction rods. Can you suggest any good reading so i can understand bump steer a little better and how adjustable traction rods will affect it?

I'm not too sure the guy who does my wheel alignments will know what i'm on about... last time i got him to do a wheel alignment on my 32 he did it to the specs for a 300zx :D Not much choice of where to go where i live though :rofl:

Sydneykid Grand Master

Sydneykid

Posted
Posted
Ok this interests me as i have aftermarket rear upper arms but no aftermarket traction rods. Can you suggest any good reading so i can understand bump steer a little better and how adjustable traction rods will affect it?

I'm not too sure the guy who does my wheel alignments will know what i'm on about... last time i got him to do a wheel alignment on my 32 he did it to the specs for a 300zx :thumbsup: Not much choice of where to go where i live though :thumbsup:

Rear bump steer is simple to measure. Take the spring and shock unit out of one side, disconnect that side swaybar link, stick the car on the wheel aligner, supporting the chassis at normal ride height of course and then measure the toe change (with the wheel aligner) as you jack that wheel up and down. Ideally there shouldn't be any change in the toe.

If you have adjustable traction rods then you simply adjust them to minimise the toe change.

I guess you already know that even by replacing the upper control arms (and traction rods) you have still left the soft, standard, old, worn out, rubber bushes in the uprights (hubs). So you are going to get some movement in toe as a result of that.

Cheers

Gary

Psymon Mentor

Psymon

Posted
Posted

Ahh thanks for that SK, that makes it a lot easier to understand! :thumbsup:

The bushes you mention in the hubs, is there an aftermarket option available? Also are they a diy job or something that has to be pressed in/out? Might give me something to do one weekend!

Cheers

Simon

Sydneykid Grand Master

Sydneykid

Posted
Posted
Ahh thanks for that SK, that makes it a lot easier to understand! :D

The bushes you mention in the hubs, is there an aftermarket option available? Also are they a diy job or something that has to be pressed in/out? Might give me something to do one weekend!

Cheers

Simon

You guessed it, it's a pain in the ass job, you have to remove the uprights (hubs) and stick them in a press to remove the old bushes. I use the Whiteline rear camber kit ($125 on the Group Buy) and the 2 piece bushes just push in with your fingers, then it's just a tap with the hammer to fit the crush tubes.

Cheers

Gary

Sydneykid Grand Master

Sydneykid

Posted
Posted
SYDNEY KID CAN YOU CONTACT ME !!! YOU`VE SENT ME THE WRONG SUSPENSION KIT. I HAVE R34 NOT R33. STOP IGONRING ME PLEASE.

Nobody is ignoring you. We get 40 to 50 PM's and emails a day, sometimes I have to actually do some work so I don't get to answer every PM and email every day. But I can assure you every single PM and every single email gets answered in the order in which we receive them. Sticking posts in innapropriate threads won't help you jump the que.

Cheers

Gary

neo32 Experienced

neo32

Posted
Posted

what are the rubber bushes in the hubs

?

Rear bump steer is simple to measure. Take the spring and shock unit out of one side, disconnect that side swaybar link, stick the car on the wheel aligner, supporting the chassis at normal ride height of course and then measure the toe change (with the wheel aligner) as you jack that wheel up and down. Ideally there shouldn't be any change in the toe.

If you have adjustable traction rods then you simply adjust them to minimise the toe change.

I guess you already know that even by replacing the upper control arms (and traction rods) you have still left the soft, standard, old, worn out, rubber bushes in the uprights (hubs). So you are going to get some movement in toe as a result of that.

Cheers

Gary

Sydneykid Grand Master

Sydneykid

Posted
Posted
what are the rubber bushes in the hubs?

Where the upper control arm and the traction rod are bolted to the upright (hub) there are rubber bushes, generally called the outer pivot point. They are pressed into the upright (hub). So you need to remove the uprights (hubs) from the car to press them out. They are the same physical size as the inner pivot points which are located in the arms.

Cheers

Gary

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