miniVan wrote:
few questions
what do i need to have adjustable camber front/rear?
what do i need to have adjustable toe on rear?
does a rear sway bar reduce road holding of rear hence less understeer because it oversteers before this occurs or does in increase road holding of front to reduce understeer
No one else seems to want to answer this so I might have a go. Sway, or to get pedantic anti-roll bars primary task is to stop unwanted weight transfer caused by body roll. If the front wheels see less weight in a corner then they "push" or understeer less. Anti-roll bars also have other side effects but I would have to get the book of words out as I forget what they are.
Negative camber adjustment is an attempt to present a flat tyre patch to the road during cornering when the lateral loads are attempting to make the car lift on one side. Obviously with ant-roll bars this effect is lessened. Also if a car has had a static ride height change (been lowered or raised) the camber will change and most likely not be ideal. Added adjustments allow us to deal with this. I would think with a mini that the amount of static neg camber required would be very small and I will be setting mine up to zero initially. The more camber you run the less tyre patch is used in a straight line and the tyres wear unevenly will eventually start to tram track which is bloody annoying. Tyres being expensive things, this is to be avoided if you are a tight arse like me. On the track neg camber is run optimally and the wear factor is not a concern.
Adjustable rear toe though I have never used it will effect the way the vehicle turns into a corner and most probably track (I,m guessing here). I reckon that if you got it wrong the car would be non-linear in its response to the steering wheel though I could be wrong here as I admit to never having tried it.
Caster is the amount of trail the road wheel is set up with behind the King Pin axis. The more it has the heavier the steering will be and the more self centering action it will have. The more it has will also cause the car to track better in a straight line.
I have never wheel aligned a Mini but I know that when I do the driver will definitly be sitting in the car with a half load of fuel in the tank(s). The small size of the car loaded with a driver and fuel would have a fairly big effect on static settings and if the guy doing the alignment didn't like it I will go elsewhere, especially if the car had had a ride height change and has the adjustments to deal with the changes.
Other people obviously fit caster/camber adjusters for road use. What settings do they run? Also rear toe settings would be interesting. Better to get it right the first time than waste money and time chasing something like this. A lot of W/A operaters have got very little knoowledge beyond the book. Find a guy with FWD race experience if you can. FWD runs different toe settings to RWD. Mid engined cars like an MR2 are different again. A mate of mine has and MR2 which had the settings changed by someone who didn't understand what he was doing and it was evil. we had to hunt high and low to find someone to fix it. That is another point. When the car is set up and right get all the settings for future reference.
Fred Puhn wrote good book on chassis design and modifications and I believe it has been revised and updated. It is worth getting, It is an easy read for those who have very little knowledge of the subject. My son has been reading it and he can't find it at the moment so I cannot check the full title of the book. Any good automotive book shop would know it. Also if you Google these search terms you will find out a lot more. I don't know much about car suspensions as I am into karts and all my knowledge derives from that.
