Driving with a Quaife diff...

[Benn]

Lee caster is at the top in grey... Or is that the std settings?

My beam is disk fitted, but at the same time but hubs are spaced a small amount(due to the abs bit in the middle) which is something i'm gonna be looking at, as ive been thinking that it gonna be that causing the rear to feel light as it will be heading left..

But that's the first tracking report i remember seeing it on... And i cant remember if it was like it before i swapped to the disk beam.

[Gordo]

Hub shouldn't make a difference, as they're concentric on the subs - the whole beam may be FUBARed.
Not sure what the track is on those cars, but over 48", that would be the equivalent of a traight beam being 2 1/2" further back/forward than the other.

[lee303]

the hubs can and do make a difference, especially if spaced badly, or the carrier is welded on pissed for a disc conversion, only needs a small amount for the toe to be affected

benn, the pic of your geo does not show any castor figures, the figures under the grey bit are for the camber, looks a pretty **** geo print out imo, go somewhere else and get a new one, with castor included!

[Sprinter]

If it were me and mine, i'd be sorting that back end out before i even thought about the front or getting used to the handling characteristics of a quaife.

[Benn]

the hubs can and do make a difference, especially if spaced badly, or the carrier is welded on pissed for a disc conversion, only needs a small amount for the toe to be affected

benn, the pic of your geo does not show any castor figures, the figures under the grey bit are for the camber, looks a pretty **** geo print out imo, go somewhere else and get a new one, with castor included!

As with the other thread, ive thought it was on the hub side. As i dont remember having the prob before. and ok i thought they where the caster fig. No clue where does any more of a set up than what i have, as as dont do camber.

If it were me and mine, i'd be sorting that back end out before i even thought about the front or getting used to the handling characteristics of a quaife.

Ok, cheers guys, i'll work on the back first. Then learn to drive with the diff.

[DarrenH]

logically, if those figures at the top were castor, then youd be missing front camber instead.

to me, greyed out means not measured, and it even has --- above it.

i agree with lee, the printout isnt useless but i stared at it for ages trying to work out what is going on. its very confusing, arrows pointing this way, arrows pointing that.

but to try and interpolate, the blue triangle i am guessing means forwardards or car facing this way. meaning stuff at the top is front wheels, stuff at the bottom is rear.

camber

front left (passenger side) negative 2 degrees, 30 minutes
front right (drivers side) negative 2 degrees, 36 minutes
rear left (passenger side) negative 1 degrees, 18 minutes
rear right (drivers side) negative 0 degrees, 6 minutes

toe

front left (passenger side) negative 0.3mm
front right (drivers side) negative 0.6mm
rear left (passenger side) negative 3.1mm
rear right (drivers side) positive 2.8mm

so for the rear toe, the rear left wheel is toeing in (i.e front edge of the wheel closer to the middle of the car) the rear right is toeing out 2.8mm (front edge of the tyre farther from the middle of the car) the picture for the rear wheels is wrong it should be like this / / not like this \ \

general observations, although i only have a laymans grasp on geometry...

too much front camber (for a road car)
front wheels should be toeing out (in total) not toeing in, as its front wheel drive the wheels have a tendancy to toe in more when you accelerate so that wont be helping

rear left camber ok
rear right camber, not enough, or atleast should be equal both sides

i dont know what your rear toe should be, or what is desirable but obviously you have a massive inbalance and the rear is crabbing

[Tathan]

I'd say that camber is about ok, 2.5 degrees isn't excessive for a fast car (obviously will use tyres a bit though). Depends on caster and roll resistance too though so play with it a bit. Camber on rear - like Darren says equal is important, anywhere in that range would be an ok starting point. Spot on with toe as regards the front. The rear I would try and get straight, you could toe it out a touch maybe but you might end up wearing the landscape for a hat.

[Brett]

I find the best thing to do is feed more power in as I feel the diff working, the effect of the diff pulling you round the bend becomes more pronounced as the power increases. In the Cav I have a crappy 5 turn rack and I actually have to take lock of sometimes once the diff starts to work hard. For me, its all about confidence which takes a bit of time to get as because where once you'd have sailed into the hedge/barrier, you now have this magic ability to make the apex's.

[Benn]

logically, if those figures at the top were castor, then youd be missing front camber instead.

to me, greyed out means not measured, and it even has --- above it.

i agree with lee, the printout isnt useless but i stared at it for ages trying to work out what is going on. its very confusing, arrows pointing this way, arrows pointing that.

but to try and interpolate, the blue triangle i am guessing means forwardards or car facing this way. meaning stuff at the top is front wheels, stuff at the bottom is rear.

camber

front left (passenger side) negative 2 degrees, 30 minutes
front right (drivers side) negative 2 degrees, 36 minutes
rear left (passenger side) negative 1 degrees, 18 minutes
rear right (drivers side) negative 0 degrees, 6 minutes

toe

front left (passenger side) negative 0.3mm
front right (drivers side) negative 0.6mm
rear left (passenger side) negative 3.1mm
rear right (drivers side) positive 2.8mm

so for the rear toe, the rear left wheel is toeing in (i.e front edge of the wheel closer to the middle of the car) the rear right is toeing out 2.8mm (front edge of the tyre farther from the middle of the car) the picture for the rear wheels is wrong it should be like this / / not like this \ \

general observations, although i only have a laymans grasp on geometry...

too much front camber (for a road car)
front wheels should be toeing out (in total) not toeing in, as its front wheel drive the wheels have a tendancy to toe in more when you accelerate so that wont be helping

rear left camber ok
rear right camber, not enough, or atleast should be equal both sides

i dont know what your rear toe should be, or what is desirable but obviously you have a massive inbalance and the rear is crabbing

Yeah i have a very basic grasp on it, i took it on a fixed rear beam, toe should be | | as mine being \ \ will make the rear wanna steer to the left, giving me the light feeling i get.
I know i have bad camber on the front, its a very low Nova. Castor wise, the wheel looks kinda center of the arch..

I'd say that camber is about ok, 2.5 degrees isn't excessive for a fast car (obviously will use tyres a bit though). Depends on caster and roll resistance too though so play with it a bit. Camber on rear - like Darren says equal is important, anywhere in that range would be an ok starting point. Spot on with toe as regards the front. The rear I would try and get straight, you could toe it out a touch maybe but you might end up wearing the landscape for a hat.

Surely with a fixed beam you wont get camber on the rear.. But yes i need to fix the toe probs first.

I find the best thing to do is feed more power in as I feel the diff working, the effect of the diff pulling you round the bend becomes more pronounced as the power increases. In the Cav I have a crappy 5 turn rack and I actually have to take lock of sometimes once the diff starts to work hard. For me, its all about confidence which takes a bit of time to get as because where once you'd have sailed into the hedge/barrier, you now have this magic ability to make the apex's.

Cheers Brett, i need to do a lot of cornering where i can test and learn this.

[lee303]

Surely with a fixed beam you wont get camber on the rear.. But yes i need to fix the toe probs first.

you will get camber, just depends how the hub carrier is welded on, you want a little bit of neg, i run 2 degrees on mine but 1-1.5 on a road car would be a good ball park figure

[Benn]

Ah ok, didn't think you would. See when i bought the beam, i never thought of checking it.

So camber on the n/s/r is just about ok, could add a bit more on the o/s/r, but toe is the main one to sort.

The top grey ones are the castor readings. They just don't adjust castor as you cant normally.

[Tathan]

Camber and toe are adjusted the same on a rear beam, just 90 deg out lol. Either need to shim things or cut and reweld if it's miles off or replace if bent.

[chip]

Sound like you just need to loosen the rear beam bolts, rotate it a bit and then bolt it back on, there is a little play in how it fits after all, and im sure you can make a little more adjustment if required.
I'd get the rear toe tested somewhere else first though, just to confirm.

[lee303]

i very much doubt you’ll get rid of 3 degrees of toe by loosening the beam mounts, they are shot holes not slots after all, it bound to be to do with the rear disc conversion

[chip]

Well its certainly worth a try as there is some play, although like you say I doubt it will solve it totally if its as described unless he slots the holes.
First thing is to get it check elsewhere though to confirm before making any mechanical changes, could easily be a misreading and its just his steering wheel isnt straight so the front ended up pointing one way which made the back look like it was pointing the other or something else like that.

[lee303]

but why should you have to slot the holes to solve it? almost certainly in the ‘disc’ beam manufacture, so sort that and presto!....

[DarrenH]

obviously someone dropped a hazelnut down the gap when it was assembled, then it went squiffy from there.

[Benn]

Cheers for the input Chip,

When i can get the beam off i will, then i can see if its the disc plates, or the hubs sitting off.

No hazelnuts, not a fan of the taste.

[Tathan]

Hmmm.