When ever i see photos of my car on track days its lifting the inside front wheel. Is there a cure for this? Any suggestions welcome?
I cant see what the problem is that looks fab
it seems to be rolling and squatting. I would try increasing the spring rates at the rear particularly and consider fitting anti roll bars or uprating if you already have some.
quote:
Originally posted by Antnicuk
When ever i see photos of my car on track days its lifting the inside front wheel. Is there a cure for this? Any suggestions welcome?
i have just gone up from 250lb to 275 on the rear, the fronts are 300lbs, i have a massive antiroll bar on the front set on the firmest settiing.
Is it wrong to have the same spring poundage on the rear as on the front?
It doesnt feel very understeery but if ever does slide at the front on tighter bends, a quick blip of the throttle soon brings the back round
I prefer oversteer, i can deal with that but i hate undertseer
The pic was taken today.
[Edited on 24-4-10 by Antnicuk]
Take corners slower? 
I thought fronts were usually a lower rate than the rear.
Doesn't front sliding wide = understeer?
I'm not sure it's a terrible thing, unless it's picking up under slow corners under braking, where it is a bad thing.
Personally, I wouldn't want to stiffen up the rear end too much, because with all of that turbo grunt, the last thing you need is less
traction.
You already have an adjustable front roll bar.
Why not fit a rear one and bring the back one into play gradually whilst easing the front one off gradually. Try and find a balance that way without
increasing spring stifness
How does the car actually feel whilst it's cocking a wheel like this ?
P.S. It never harmed the great Jim Clark. Once he knew the Lotus Cortina did this, he used it to his advantage and got tighter into the corner.
quote:
Originally posted by Antnicuk
i have a massive antiroll bar on the front set on the firmest settiing.
I don't actually think it's a very serious problem. I've seen plenty of cars do this - and I'm sure I've seen pics of F1 cars
doing it.
the inside front wheel doesn't do a lot on exit from a corner as all the weight is on the outer wheel anyway. A more serious problem is if the
inside rear wheel spins up thus losing drive out of corners. if this happens a lot it's time to get a LSD.
As mook says, its not a bad thing unless you're missing front end grip.
Any weight that isnt on the inside front is on the outside rear, which is where you want it on the exit of a corner for more rear end traction
i will try and ease of the arb ( meant to do it today at the track but i was having too much fun)
It doesnt do it on bigger bends, only smaller ones. Although i am very agressive which im sure doesnt help
I have a silva style rear so i have opposing trailing arms meaning that the live axle acts as an arb from what i understand.
I found that bend n the photo, which always seems to have the most lift, particularly hard to get right. Its hard to tell whats going due to my
inexperience and the car is a bit manic! great fun though!
The rear is so controllable and i can make the front or rear slide depending on what i do, it makes the car really easy to control beond the limit
and it will get very sideways and as long as im quick, i can keep it going in the direction i want.
It would be nice to feel a bit more planted in the corners though instead of having to fight it round the track. In the technical tight bits i found
stabbing the brakes as i went into a tighter corner improved front end tration and not getting on the gas too early helped eliminate any understeer in
the tight bends.
Not sure if this is right 
[Edited on 24-4-10 by Antnicuk]
Sounds like backing off the ARB will definitely help!
quote:
Originally posted by Antnicuk
I have a silva style rear so i have opposing trailing arms meaning that the live axle acts as an arb from what i understand.
Soften the front ARB and stiffen the rear. As the outside front suspension is compressed the front ARB is trying to prevent the inside suspension
extending and it lifts.
But if the balance is good and it's not understeering...
adrian
with a live axle it is much simpler - the rear roll is entirely a function of the spring rates.
If you over do it on the spring rates then it will get very skittish at the rear so maybe try another step up at the rear to see how you like it but
be prepared to go back to the current ones if you don't like it.
as you are finding out - car set up is a compromise. if you get it working well on that slow corner then it might not be as good on the faster corners
as it is currently. So have a mess about with spring rates and see how you get on
thanks guys, i will have a play with the arb.
Dont shout at me but i rose joint the rear arms at the chassis ends and the axle ends are poly bushed, people have said its wrong but it works well
for me i think
quote:
Originally posted by Antnicuk
It doesnt feel very understeery but if ever does slide at the front on tighter bends, a quick blip of the throttle soon brings the back round
quote:
Originally posted by JoelP
quote:
Originally posted by Antnicuk
It doesnt feel very understeery but if ever does slide at the front on tighter bends, a quick blip of the throttle soon brings the back round
That sounds like it does understeer when pressed. With only one wheel on the ground you will get less grip turning in. The 205s etc lift a rear wheel cos (i think) its a torsion bar at the back which cannot bend much, ie its like it has a tough antiroll bar. You have the same at the front. As the body rolls the wheel gets lifted by the ARB.
TBH, myself id take it off entirely and see how different it is, you will get a much more noticable difference than if you just adjust it slightly. Then you can see if you prefer it with or without.
Or, splash out, take it to someone who knows kit handling well, and let them fiddle.
I have
fitted a 24mm rear ARB though.
The issue with 205's, as with many hatch's and to a certain extend the OP's car, is roll axis inclination. The front and rear roll
centres are at different heights-on the floor on the back of a 205, and about 4"-6" on the front depending on lowering, on most live axles
it's at the axle centre height, so maybe 8"-10" depending on wheels.
This then causes the front and rear to roll at different rates, skewing the body, not just lifting the wheel.
As above, softening the front ARB may help, failing that try and lift the front roll centre, even if everything else on the car is wrong, and see how
it rolls.
[Edited on 25/4/10 by brianthemagical]
It dosen't look too bad but the front arb is too stiff, once you stiffen the front roll stiffness beyond a certain point you get 100% weight
transfer and increasing the front roll stiffness further has no effect.
Reduce the front anti roll bar stiffness and stiffen the rear springs relative to the front both of which will reduce understeer and may push you
into an oversteer situation --- an oversteering feels fast but isn't so test against the stop watch.
Order order doing things
(1) Reduce anti roll bar stiffness --- and test
(2) Swap front and rear springs --- and test
If that gives you too much oversteer try fitting a set of 300lb/in springs to the front rather than stiffen the arb.
[Edited on 25/4/10 by britishtrident]
Ive got some 300 lbs springs you can have for a token beer
quote:
Originally posted by mookaloid
with a live axle it is much simpler - the rear roll is entirely a function of the spring rates.
quote:
Originally posted by MikeRJ
quote:
Originally posted by mookaloid
with a live axle it is much simpler - the rear roll is entirely a function of the spring rates.
quote:
on the live axle Striker/Fury etc. They have built in roll stiffness due to using a watts linkage for longitudinal location of the axle at each side instead of the standard 4 link setup. In roll the linkages try to twist the axle and the deflection of the rubber bushes in the linkages determines roll stiffness (+ springs obviously).
I didn't realise that the striker uses a watts linkage. So thinking about it - it would be a bad idea to make a watts linkage using rose joints then?
quote:
OP's picture remind me very much of Mk1/Mk2 Escorts that I see on local tarmac rallies; for some reason they always seem to have far too much roll stiffness at the front and end up with the inside front wheel way up in the air.
I have seen many escorts doing this too - they seem to get round the corners ok
quote:
Originally posted by MikeRJ
The OP's picture remind me very much of Mk1/Mk2 Escorts that I see on local tarmac rallies; for some reason they always seem to have far too much roll stiffness at the front and end up with the inside front wheel way up in the air.
[Edited on 25/4/10 by MikeRJ]
The stylus doesn't use a watts linkage, good old pan hard rod
how muchbeer for the springs and are they 8 inch?
[Edited on 25-4-10 by Antnicuk]
quote:
Originally posted by mookaloid
quote:
Originally posted by MikeRJ
quote:
Originally posted by mookaloid
with a live axle it is much simpler - the rear roll is entirely a function of the spring rates.
quote:
on the live axle Striker/Fury etc. They have built in roll stiffness due to using a watts linkage for longitudinal location of the axle at each side instead of the standard 4 link setup. In roll the linkages try to twist the axle and the deflection of the rubber bushes in the linkages determines roll stiffness (+ springs obviously).
I didn't realise that the striker uses a watts linkage. So thinking about it - it would be a bad idea to make a watts linkage using rose joints then?
quote:
OP's picture remind me very much of Mk1/Mk2 Escorts that I see on local tarmac rallies; for some reason they always seem to have far too much roll stiffness at the front and end up with the inside front wheel way up in the air.
I have seen many escorts doing this too - they seem to get round the corners ok
Miglia's can do it as well.
We had the very same problem on our Indy. It always lifted the inside front wheel on one particular corner at Teeside. Fitted some heavier springs on
the rear which sorted the issue.
Phil
thanks guys, even with the 275's on the back it doesnt seem to hard on the road, especially with the shocks softened a bit and it still squates loads under power so i could probably try 300's and it wouldnt be too stiff.
quote:
Originally posted by Hellfire
We had the very same problem on our Indy. It always lifted the inside front wheel on one particular corner at Teeside. Fitted some heavier springs on the rear which sorted the issue.
Phil
quote:
Originally posted by Antnicuk
The stylus doesn't use a watts linkage, good old pan hard rod
quote:
Originally posted by mookaloid
I didn't realise that the striker uses a watts linkage. So thinking about it - it would be a bad idea to make a watts linkage using rose joints then?
Yep, that is the one. Or maybe I should say 'that was the one........
Phil
quote:
Originally posted by MikeRJ
quote:
Originally posted by Antnicuk
The stylus doesn't use a watts linkage, good old pan hard rod
We aren't referring to lateral location, the Striker and Fury also use a panhard rod for this.
The Watts linkage in this case is used instead the two trailing arms at each end of the axle that more traditional chassis use. I don't know if the Stylus uses this though.
quote:
Originally posted by mookaloid
I didn't realise that the striker uses a watts linkage. So thinking about it - it would be a bad idea to make a watts linkage using rose joints then?
Very bad idea, you would be breaking the brackets of the axle/chassis for a pass time.
quote:
Originally posted by Antnicuk
I still dont fully understand the exactly the issue of the bushes making the whole system work.
I won't bother repeating the above, but it's why I asked the Q's I did of you in this post. The above is correct - With your setup,
something has to give, be it the bushes, the brackets or the prop, something HAS to give.
You fitting RJ's can only exacerbate the situation IM(humble)O...
Thanks for the info, I still have bushes at the axle so there is some compliance.
I'm not sure about something having to give. Most mounting points on a car have various stresses and strains, from suspension and engines to
seat belts, but we make the points strong enough to with stand the amount of stress the car will give it, rather than identifying a week point and
using bushes to compensate and give the mounting an easy life.
A chassis takes stress and wants to flex but we triangulate them and reinforce them untill it is prevented from doing so.
Am I missing the point some where? Is there some other reason for wanting compliance? Does it improve geomitry under load or something?
If it wasn't for comfort we wouldn't use bushes anywhere, surely?
These are just my inexperienced thoughts
[Edited on 26-4-10 by Antnicuk]
The sylva setup - two trailing arms / two leading arms.
Never ever liked it, for the reasons described above.
When I first saw it on a striker, I couldn't get my head around it, the trailing and leading arms are describing different arcs, so even in a
straight line, there has to be compliance in the bushes to make it work if you take axle rotation out of the equation.
I'm as much a JP fan as anyone, but I honestly can't think of what he was smoking when he thought that this was the best solution.
Then again, that's car designers. The courage of your convictions and all that.
How it shoudl be, I guess.
quote:
Originally posted by Antnicuk
Thanks for the info, I still have bushes at the axle so there is some compliance.
I'm not sure about something having to give. Most mounting points on a car have various stresses and strains, from suspension and engines to seat belts, but we make the points strong enough to with stand the amount of stress the car will give it,
quote:
Originally posted by zilspeed
The sylva setup - two trailing arms / two leading arms.
Never ever liked it, for the reasons described above.
When I first saw it on a striker, I couldn't get my head around it, the trailing and leading arms are describing different arcs, so even in a straight line, there has to be compliance in the bushes to make it work if you take axle rotation out of the equation.
I'm as much a JP fan as anyone, but I honestly can't think of what he was smoking when he thought that this was the best solution.
Then again, that's car designers. The courage of your convictions and all that.
How it shoudl be, I guess.