17 replies to this topic

[neglectedtorana]

Hi All,

 

I was reading about the drive south hatch and saw this pic and got to wondering, as I don't know.

How much camber is necessary and what is the extra negative camber hoping to achieve?

 

My understanding is as the suspension loads up in a corner and having extra negative camber will mean the tyre has a bigger contact patch when being pushed hard. Is this correct?

If so when cornering is the desired result to have the bottom of the tyre flat on the ground?

 

Pict below is why I am thinking about it. 

I don't know enough about suspension to know whats going on but am interested to know if this is how the tyres are meant to look in a corner?

Not knocking the car in the pic just wanting to know.

 

Any simple explanations that would help understanding wolud be appreciated.

 

Cheers, Tom

 

[claysummers]

Personally, and on a road car, I set the camber to achieve even tyre wear across the tread. Because the outside tyre takes most of the cornering force I suppose, my tyres would wear on the outside edge under factory settings. Actually it is because I tend to corner fairly hard, or at least I used to. So adding a degree or two negative camber and perhaps running a bit more pressure, evens this out across the width of the front tyres.


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[RallyRed]

Thinking that - as the car corners, the car rolls over, the suspension compress, the bushes squish and the tyre tucks under the wheel.  All meaning that the full tyre surface is no longer contacting the road. The outside edge is doing all the work. 

Thus the full ability of the tyre to stick to the road, and help the car go where you are pointing it is lost.

By adding -ve camber and leaning the top of the tyre in/ bottom of the tyre out, there is more chance of the full tyre contact happening, as all of the above occurs, the tyre is more likely to end up square to the road, and not tucked under.

 

Critical for racing etc, but for road use, big -ve camber will just trash your road tyres, as they will run on the inside edge all the time.

Best to stick to factory specs for road use, or maybe a smidge more.

[Bruiser]

Those are good advices already
If we set our daily cars up like that beautiful red thing in your picture the tyres would be flogged in a month or less
Bald on the inside , obviously
But in say a fast long left hander, the load plants onto the right front tyre that kind of wheel alignment angle results in the tyre contact patch
being flatter on the road, resulting in mucho racing cornering grippo.
Race setups can have this done to the rear wheels as well - easy with independent rear ends, but I reckon
they bend a couple of degrees into a normal solid diff for some of the same effect

[claysummers]

I reckon we could have a go at the rear axle in your VK Bruce. Run a series of spot welds along the top of the housing with a mig.


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[axistr]

The red hatch in the photo has too much neg camber for a wet setup. When Torana's were raced back in the seventies cambers between 3&6 deg neg was the norm. Wind the clock forward forty years. With better shocks, springs, tyres, suspension bushes, stiffer chassis and sway bar technology improvements you can reduce the amount of negative camber for racing. However these were all track car setting. As mentioned above this setup will kill tyres for street driven cars in no time. You just can't go through every street corner at full speed all time to benefit from lots of negative camber for street use. Furthermore track cars pit for new tyres 3 or four time in 1,000km. For the average driver and street use only I generally try and keep the cambers around 1/2 deg negative static left side, 1/4 negative right. Slow cruisers zero camber right and 1/4 negative on the left.          

[Bruiser]

I reckon we could have a go at the rear axle in your VK Bruce. Run a series of spot welds along the top of the housing with a mig.


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Hah, maybe a couple of dukes of hazard jumps with a nice hard landing would do the same thing.
End up with something like this
The tyre bill would be unbelievable
Had a mini-spool years ago, that ate the tyres fast. Only one pair before it was turfed
Never again
 IMG_0801.jpeg   72.44K   2 downloads

[RallyRed]

Those JDM style things just look whacky IMHO.

 

Regarding rear wheel camber, for solid axle rear ends, just need to remember that you have a parallel splined axle going into a parallel splined diff centre, for about 40mm? Not too much articulation possible there..........

( talking factory Banjo type setups ).

[Bruiser]

Anything I have ever read only talks about a degree or so, a tiny bit.
It does seem daft though, and wear thing out a bit quick.
I’d just put some washers on the two lowest wheel studs

[claysummers]

Anything I have ever read only talks about a degree or so, a tiny bit.
It does seem daft though, and wear thing out a bit quick.
I’d just put some washers on the two lowest wheel studs

That’d work, 2/5 of the time I suppose.


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[neglectedtorana]

Thanks guys,
All those explanations work well for me.

I have read all the posts about setting up a front end but the practical description works better for me to understand than just the figures.

I often see a ricer with the wheels leaning in so much it looks like you don't get full tyre contact and definitely more wear and wonder why some people do that but it's likely to be something I will never understand and not related to good handling.

Happy driving,

Cheers, Tom

[claysummers]

Yes, it is hard to believe that people set their alignments for appearance. Young local bloke did my FB and set it up with minimal caster, apparently so the tyres wouldn't rub. Well, so he said. It was quite unstable at speed, so I took it home and redistributed some of the adjustment wedges from front to back, keeping the camber as set, but dialing in a couple more degrees of positive caster. The difference was significant. Oh, and the tyres ony rub a bit now and then......

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[Rockoz]

I remember reading an article many years ago.

I think it was an interview with Bondy.

The discussion was about setting up cars for the low budget guys in wheel alignment terms.

A lot of the blokes were setting up the suspension to make it easier and lighter to steer.

He would do a lap in their car and then tell them to reset the camber usually.

It made the car a lot harder to turn, but their lap times reduced dramatically.

Road cars are set up for easier driving, and obviously lower wear, and race cars are set up for speed.

 

Cheers

 

Rob

[Heath]

^ Rob, that sounds like he's adjusting castor, not camber.

Personally, and on a road car, I set the camber to achieve even tyre wear across the tread. Because the outside tyre takes most of the cornering force I suppose, my tyres would wear on the outside edge under factory settings. Actually it is because I tend to corner fairly hard, or at least I used to. So adding a degree or two negative camber and perhaps running a bit more pressure, evens this out across the width of the front tyres.

 
Yeah, pretty much this. Basically the best camber for a car is the one that gives you even tyre wear (on a track, this is usually what gives you relatively even tyre temperature). On a car that does mostly highway k's, that is going to be close to zero. On a car that only does circuit work, that is going to be massively negative. On a road car... depends on how you drive it.

If I had say 0.25deg of negative camber on the front of my Torana, the outside of my tyres would be scrubbed smooth after a few spirited driving days in the hills. (I run 2deg negative)
I also have 0.5 degrees of negative camber in the rear of my Torana (live axle).
Tyre wear is nice and even on all four corners.

The other thing that has not been mentioned here is castor. A late model car like my old GXE10 or JZX100 has like... 7 degrees of +ve castor? So it doesn't need half as much static camber to tilt the wheel over in a corner.
A car like a Torana (particularly with no power steering) is going to have less than half of that castor, so more of a compromise is needed, in the form of static camber. This is not ideal, as (front) camber hurts tyre wear and braking performance.

And yes, a lot of people will adjust camber to suit wheel clearance (when striving to maximise wheel dish) or other styling preferences.

I love the look of a good amount of negative camber. For example if you say you don't get a stiffy when you see a '69 Camaro with a side pipe, R-spec rubber, and big negative camber on the front, you're probably not being honest with yourself.

[claysummers]

Heath, I’m interested to know your experience regarding driving noise and wear on the rear splines and spider gears. I think I recall you used the spot weld method to bend the housing?


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[Bruiser]

Sounds like you were up the right tree anyway Tom, your ideas were pretty right
The car in your pic isn’t pushing hard enough in that bend to plant the outside tyre fully.
Doesn’t look like a tight bend, but he just might be going easy in the wet.
I like Heath’s sum up, the best setup depends on how you drive it.
What is best for grip during a good hard flap in the hills or on a track won’t be best
for straight highway driving or grannying along. Yet another car modifier’s compromise
Cool if you understand your tyre wear enough to know what to ask the alignment guy for.
If we hit corners hard like those hoons Clay or Heath, some -ve is a good thing for us.
I remember seeing here some time ago someone’s wheel alignment report and found these ones.
Not sure if it is the same one, but the rear camber figures are interesting
I assume these are unmolested diffs, but one shows almost half a degree negative
Read something on Google, the guy stating “ a diff will bend that way over time on it’s own” or words
to that effect.. take that as you will
 IMG_0805.jpeg   64.75K   6 downloads

Here’s another with 0.17 negative

 IMG_0806.png   31.86K   7 downloads

[claysummers]

Is that 14mm toe out? Crikey!


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[neglectedtorana]

My wheel alignment guy has a Hatchback and said he wouldn't add too much as it isn't worth it for a street car that sees some track time unless you have slicks.

I will have to check the paperwork but think its less than .5 degrees neg and he did vary if left to right to suit tyre wear and wonky roads.

 

He did mention my diff has some positive camber which is unfortunate and if I ever get anything done to the diff to get them to fix that and make it slightly negative. I am guessing the slightly positive was an accident.

 

I am pretty happy with how my car drives so unlikely to make any major changes.

Just saw that pic and wondered if it was how things should look but not surprised it isn't necessary.