Really whats important is the relative proportion of spring to arb resistance - an arb cannot make a wheel loose traction if the spring is strong enough to resist Anyone ever actually measured wheel rates for spring and arb setups????? I have. Love to know if others have also.....
Not yet, still need to learn how to measure wheel rates full stop. lol One day when I have some more time and the car is actually in one piece.
just to bring this back to life - i've read all 3 pages but understood bugger all of it tbh! i don't run a track track but a low daily vento - approx 100mm lower than standard. the spring rates are 375lbs front (6" long) and 275lbs rear (10" long) GAZ struts with 36 point damping (set to point 8) and its nice and stiff. i've been thinking of removing front arb to aid turn in a little over crap camber roads etc but not sure if this would work well on a road car with road tyres? car has also been fitted with ball joint extenders, camber adjustable top mounts and compbrake formula r track rod end flipped to under the hub.
You have not asked what about what you really want? 100mm lower sounds a lot, are your wishbones horizontal?
Ok bad explanation, basically the front corners feel to tied together if that makes sense Nd not independent enough of each other when going over heavily cambered roads or uneven surfaces. I wondered if removing the anti roll bar would free up the front end corners a little but with the spring rates would it go all floppy and roll? Wishbones are flat if that's what you mean, from chassis to ball joint now thanks to extenders, so are steering arms - was done to assist with bump steer. It's not a track car, and will never handle like one at the height it's at but I would like to improve the steering feel if that makes sense. As said before I didn't understand all the stuff about Hz and stuff and ratios but its not a track car so is this important? Sorry if I'm asking in the wrong place
I see, you want to know if removing the arb would be good, well I'm with rob on this, I like them, however, you could disconnect it from the wishbones and tie it out the way and take it for a drive to feel the difference. Getting the camber and toe setup perfectly might make a big difference, I have zero toe and like it but others like a little bit of toe in. What is your camber now?
for a road car - bit of toe in for safety - for track use, hint of toe out for steering responsiveness
Think the camber is closer to -2 at mo so tyres clear the arches. Why toe in? What will this achieve? Tracking place set it parallel as that what machine said to do and complained about the camber - tyres won't last more than 3 minutes! I know camber will wear inside edge a little faster but won't tie in or out compound this further?
I would say that your geo sounds good, is the damping too stiff? Have you tried backing it right off? And then, how much suspension travel do you have? if you run the car too low you maybe sitting on/using the bumpstops most of the time. What ET are your wheels? if you KPI is positive it could have the effects you describe
In my case, I want to reduce dive, stiffer springs help that, it keeps my aero performing.I`m not convinced with your statement of `a stiffer arb won`t lose traction`. You are linking the front wheels together, reducing their ability to deal with bumps. On a track car, ride comfort isn`t as much of a consideration, so that particular downside from a stiffer spring isn`t an issue. Anyway, I`m just going on what my suspension guy said. springs first, ARB`s for fine tuning. He is FAR more knowledgeable than me, its his job and he is very good at it so I obviously listen to him
What wheel frequency are you on now nige, and what do mich recommend for those cup tyres? Stiffer springs will have much more an effect on a cars ability to deal with bumps than an arb. And springs are not easy to change at the track, or when it rains.....
I don`t know lol He asked me for the corner weights, desired ride height, camber, caster, toe, desired handling characteristic (ie I like a softer, more compliant rear than a lot of the racers have), damper travel, damper position at rest, bump stop length and a few other stuff I can`t remember, I just measured everything, sent him the information and he specced the spring rates, lengths, helper spring length and spring platform position I needed. I was meaning from a traction point of view out of corners, which is what I thought babbe meant. I make no claim of being an expert on suspension nor have the level of knowledge required to setup a car PROPERLY, I didn`t just bang a set of stiff springs or ARB`s on the car and hope it worked either. I know that`s not what you`ve done and wasn`t what I meant. I was meaning a lot of `internet experts` who just add a stiffer front / rear arb, wind the damping up to hard and then tell everyone how it `handles like its on rails`. lol
maby we should start asking what is a stiff spring? atm im running 600lbs with a knife typ arb that is spec as 45nm per side, dont know what wheel rate that gives me in reality. In my opinion that isnt hard for a track car, for this season im changing to 500lbs as its a rally car and not a track car. in my opion the traction out of a corner is more dependent on other things than the springs. camber, tyres stiff springs also reduces traction during braking bcs the car cant dive as much as it would need to. my point is. there are ppl recomending others to lose the stock arb when runnign 600lbs+ and that is just crazy. to compensate the roll from not using an arb you need to go so stiff that you start to get wheel bump and that makes you lose traction again.
It starts to become impossible to suggest what is best, because... it is almost impossible. My set-up is not 'best' because so much influences it - money, driving ability, time, testing, regulations, individual circuits, tyres, weather conditions etc etc.... as we can all list. It is interesting to hear opinions and reasons, but they will result in improvements for some and losses for others.
yeah. the one thing that determineds how stiff chassi you can have is the tyres. the worse tyres you have the less grip you have and softer the chassi needs to be.
ok, for those who have tried to help with my road car setup - massive thanks - heres a few more bits that were asked: wheels ate 7j 17 et38 with 195/40's - about the cahnge to 185/35 so clear arches better i think. i have 25-30mm of travel available before bump stops i had the GAZ suspension custom made (450) on 11" front legs so i could go low and have travel so i know it never going to be a race car and handle amazingly but it better than 99% of cars at this height (only other option was a custom stillstatic H&R kit at about 1500) from what i've now read i still don't understand the Hz thing or the question about KPI (or working it out) but the anti roll bar will stay put as thatas not the issue. going to plump for the D2 camber adjustable top mounts though and go back to the tracking machine as i'm thinking it could be the angle of the strut to the hub that i'm using to get the camber that could be making it feel 'weird' over bumps rather than the roll bar which was my first thought.
185/35 tyre...on a road car....you must be mad put 15's on it with a 50 profile tyre and your handling will be miles better
