User Login    
 + Register
  • Main navigation
Login
Username:

Password:


Lost Password?

Register now!
Fast Search
Slow Search
Google Ad



Browsing this Thread:   1 Anonymous Users



(1) 2 3 »


Re: camber
Home away from home
Joined:
2006/4/24 10:17
From Southern Highlands, NSW, Australia
Group:
Registered Users
Posts: 313
Offline
I'd agree with that, I see lots of people at supersprints fiddling around with their suspension between runs. They seem to have a fairly stressful event because they're always pulling their hair out trying to make the car handle just the way they want it. Not to mention the laptops that get hooked up to try and squeeze the last little bit of horsepower from the engine. I'm on the completely opposite end of the scale, haven't checked my wheel alignment in 2 years, basically change the oil every so often and put fuel in it.
As for camber, i'm running 4 degrees negative (most i can get) and the outside edge still wears a little bit more than the inside. All of my driving is done on the racetrack though. And caster is set at 5 degrees, the car will steer itself out of drifts if you let the steering wheel do what it wants, just keep on the throttle.

Posted on: 2009/11/20 23:37
_________________
'72 1200 sedan hillclimb/supersprint car
Transfer the post to other applications Transfer


Re: camber
No life (a.k.a. DattoMaster)
Joined:
2008/10/10 22:02
From Melbourne Australia (and likely under the car)
Group:
Registered Users
Posts: 1021
Offline
Even if you hypothetically welded up the suspension rock solid, no movement, and drove on mirror flat surfaces, you need some neg camber for corners, due to how weight transfers, and the tread will otherwise roll up and over. Then when you take 'real world' suspension that can move (and it's less pronounced on a strut front end than double wishbone) - as the car rolls during a corner (body roll) it 'twists' the strut that way too (a little) and 'robs' you of some neg camber.

Meaning, in general, you need neg camber to start with, and the more body roll there is, the more you typically want. If you have a rather rigid suspension (not much body roll) then less neg camber can get the job done. This is one of the big reasond there are different 'camps' as far as car setup goes, and why some prefer harder springs with 'average' anti roll bars, and others prefer softer springs (still harder than any factory spring setup mind you) and harder stiffer anti roll bars.

More positive caster is almost always 'great' - yes the steering is a bit 'heavier' but it also makes the car (relatively speaking) far more stable in a straight line (all else being equal). You'll still need some neg camber, as all the positive caster you can dial in still won't add enough 'active camber' as high speed turns don't really see massive steering angles.

In general - with a 1200 - I'd be fairly confident that for optimum circuit performance (but still with street tyres) you'd probably be able to dial in all the neg camber and positive caster you could physically achieve given most adjustable caster rods and strut tops, and still want a little bit more, but there is more than enough adjustment for street driving imho.

One little trick (obviously don't go ridiculous on this) if you wanted to run more neg camber on the street, experiment with a touch (we are talking a mm at a time here for testing) more toe in - which will tend to equalise straight line contact patches and even up tyre wear. Of course there's no such thing as a free lunch, and on a circuit, you'd actually go with a little bit of front 'toe OUT' to improve initial turn in (even though it will chew up the tyres quicker, it's all about lap time, not longevity for most events a 1200 would be entered in these days)

Another thing that might be considered on a streeter - too much neg camber will eventually have an impact on braking distances. On a circuit doesn't matter = since more neg camber usually means better mid corner speeds possible, so you don't miss the braking quite as much.

Last tid bit, within a narrow range- the higher the tyre pressures, the less neg camber you need (or more accurately, you'd probably improve circuit times with street radials with higher pressures than typical - the whole 'lower pressure for grip' really only works on specially made drag tyres and or dedicated race tyres with consierably different design and attributes than street radials)

Since all of these things are inter-related, you can go a bit batty trying it all out and trying to keep track of what works and what doesn't. Although good setup is critical, a tip a local racer gave me years ago (and he had the quickest car in it's class, despite a modest budget) was simply this "sometimes people spend all their time trying to get that last 0.01% out of the car through setup, they should have spent less time doing that (getting it darn close, but perhaps not perfect) and then spent a good deal of the remaining time learning/practicing and getting the most out of the potential of the current settings.' He was adamant that that was where he was kicking everyone else's backside.

Posted on: 2009/11/20 21:23
_________________
John McKenzie
Transfer the post to other applications Transfer


Re: camber
Home away from home
Joined:
2005/11/27 12:30
From Newcastle
Group:
Registered Users
Posts: 801
Offline
Camber baby lol Gota love it

Attach file:



jpg  l_b2389223bc05a88a904cec585826e356.jpg (42.93 KB)
5788_4b062531d60d7.jpg 600X450 px

Posted on: 2009/11/20 5:04
Transfer the post to other applications Transfer


Re: camber
No life (a.k.a. DattoMaster)
Joined:
2004/10/28 11:35
From Geelong, Vic
Group:
Registered Users
Posts: 6184
Offline
as long as you dont factor in stuff like the cost of adjustable castor rods, stiffer steering(not always a bad thing) and having to cut your guards

Posted on: 2009/11/20 4:57
Transfer the post to other applications Transfer


Re: camber
Moderator
Joined:
2001/5/3 7:04
From 48 North
Group:
Registered Users
Contentmaster
Usermaster
Posts: 31599
Offline
That sounds double-good!

Posted on: 2009/11/20 4:03
Transfer the post to other applications Transfer


Re: camber
No life (a.k.a. DattoMaster)
Joined:
2004/10/28 11:35
From Geelong, Vic
Group:
Registered Users
Posts: 6184
Offline
also increased castor adds camber when turning

so you can have lots of castor and minimal camber in a straight line then when you are turning you get more camber. or more neg camber on the outside wheel and the inside wheel tryes to go to positive camber....which is good

Posted on: 2009/11/20 3:42
Transfer the post to other applications Transfer


Re: camber
Moderator
Joined:
2001/5/3 7:04
From 48 North
Group:
Registered Users
Contentmaster
Usermaster
Posts: 31599
Offline
You guys may be too young to know the reasons for positive camber. Let's just say that with today's tire technology, coupled with today's AUS and USA roads, we no longer need positive camber. So yes, aim for Zero for longest tire life, or for negative camber for increased performance.

Regarding Castor, more is better, and more is worse. It won't make the steering sluggish, but instead will make it harder to turn the wheel. The Datsun 1200 steering takes a very light effort because the caster is minimal. But that's also why it wanders on the road, because the castor is minimal. With more castor it will track straighter. Depends on what you want.

Posted on: 2009/11/20 3:23
Transfer the post to other applications Transfer


Re: camber
No life (a.k.a. DattoMaster)
Joined:
2004/3/19 8:16
From Perth WA
Group:
Registered Users
Posts: 1154
Offline
I dont know,I thought wheel aligners aim for zero because u are mostly going straight ahead. it makes sense that on the road only if u r cornering hard a lot, a little bit of neg camber will make for better steering response and more even tyre wear. But for racing the setup and balance is a whole science in itself with no fixed rules, they vary from car to car and track to track and day to day.

Posted on: 2009/11/20 1:39
_________________
datsun 1000, Its not the size its how u use it.
Transfer the post to other applications Transfer


Re: camber
Home away from home
Joined:
2007/5/24 21:24
From Los Angeles,CA
Group:
Registered Users
Posts: 259
Offline
I run 1 degree negative camber on the street with super gummy Toyo R888's. Haven't noticed any appreciable uneven tire wear. However, why does everyone say you need as much positive castor as you can get? I've heard that a bunch of times. I know it's better for high speed stability and self centering, but won't it make turn in feel more sluggish? My castor is stock and I like how light the steering is, it doesn't feel overly twitchy to me. What's the story there?

Posted on: 2009/11/19 22:39
Transfer the post to other applications Transfer


Re: camber
Not too shy to talk
Joined:
2008/2/20 6:22
From Australia
Group:
Registered Users
Posts: 36
Offline
Hi, I reckon 0 to neg 0.5 is all you need for road use and tyre wear, run as much positive caster as you can adjust in, and start with about 2mm toe and then adjust toe to change turn in and tyre wear. If it scrubs the outside, to much toe in, if it scrubs inside to much toe out. Hope this is of some help.

Posted on: 2009/11/19 11:41
_________________
Datsun 1000 Sedan, Datsun 1200 Coupe,LA Lancer 2 door,Datsun 1600, Datsun C210 Skyline Coupe,BMW 320I,BMW 535I, Datsun 1000 Coupe.
Transfer the post to other applications Transfer



(1) 2 3 »



You can view topic.
You cannot start a new topic.
You cannot reply to posts.
You cannot edit your posts.
You cannot delete your posts.
You cannot add new polls.
You cannot vote in polls.
You cannot attach files to posts.
You cannot post without approval.

[Advanced Search]