Anti dive tips

[s2avant]

My front wishbones move loads as the poly bushes are shot in them. They are being replaced as part of the overhaul coming up. Sorting all the bushes and fitting the bilsteins should have a positive effect on the diving.

pixsaudisex2, can you give me some more details on exactly what you did to stop the wishbones moving. Have you got any pictures? It sounds like something for me to look into.

Ben

[meep]

Hmmm i got powerflex busshings i my frotn wishbones. Youd thikn they would stop the flexing?

What is this S4 and 300 mm disc thing that you guys are talking about? What have i missed?

[S2 PTH]

Not too go off topic here, but Im about to fit (over the next frew months) some 996 (big black) calipers to the front, but I also have the rears too. My Dad tells me to fit them but I've heard that theres problems trying to get the handbrake to work on it too? So I need some advice really... I'm sure the car will be fine for the time being with the fronts only but over time i'd like to do the rears too with the calipers that I have!

[pixsaudisex2]

a poor piccy but i just held my hand under the car to take the photo but as you can see the red is the rubber i put some on the back of each bush to help stop movment hey this may not be to every ones requirments but i found my car felt a lot more stabble under heavy braking . suppose i could have gone down the root of buying poly bushes but every car ive ever had i hate the noise they make so for once kept to the orignal bushes. but then put ally top mounts on think i might have to go back to normal strut tops soon .. again a noise thing.

[s2avant]

I see what you mean about picture quality

Am I correct in thinking the rubber is cut in a circle and is used as packing at one side of the bush to stop the wishbone moving backwards and forwards?

Ben

[Keeper of The Kitten]

So what people are actually trying to stop is the squirming around of the wishbone here, not diving? You won't stop diving by messing with the bushes, the wishbone still rotates around those points. Refer to my earlier post about wishbone mounting.

However, we cannot simply move the points, so the first genuine cure for diving is to stiffen the springing/v-low speed bump damping. But I think the problem that most people are concerned about is instability which I now believe is caused by the outboard ends being pushed back by the hard braking. In that case, stiffer wishbone bushes or packers in the bushes will make a difference.

We need to determine the real problem here - is it diving of the front end or merely instability that can be attributed to something other than diving?

__MDC__

[pixsaudisex2]

erm yes you would be right although never got around to cutting the rubber into a circle still looks kinda square...


and yep i know this isnt related to diving under brakes but it was my biggest concern after changing my brakes thats for sure ..

question is though the weight of these s2s and the speed they some times get to do you think there is any way of stopping the diving i mean surely your shocks would be that stiff to stop it that you would just need solid metal rods not shocks..


and i think you would find more problems with no diving than with diving i mean does the diving also help plant your tyres to the floor giving your tyres the grip they need when you slap your anchors on.. hum... tell you what reading this thread has made me think .. not a good thing.. not a good thing at all..

[meep]

Well yes but the problem is this When your tires are like this when braking if the car would be flat

I---I

They are like this when diving

/----\

This gives you less tire on the road Especially if you are running some rather harsh camber to start with. Inmho it would be better to stop the diving for 2 reasons.

1. More tire on the road = shorter distance to stop. Lets face it with 996 calipers the brakes arent the problem. The tire grip is.

2. Since the front tires are overwhelmed and are braking at there maximum. It would be niice to let the rear tires help out some to. One of the few ways to get more stoppign power with out Rcompound tires or positive camber

[Sir Buff]

When we change the angle of the hole subframe (with different mounts), is it the same effect?
Do you know what i mean?

Anti dive and anti squat/lift are achieved by angling the lower control arms away from the direction of the problem - in this case the rear leg of the front wishbone would be mounted higher than the front leg. At the rear, mount the front legs of the wishbones higher than the rear legs. Doesn't need to be much.

__MDC__

[Keeper of The Kitten]

To answer Sir Buff, yes, that would actually do it - I don't know if anyone would want to do that work for the possible gains. You would need to make thicker mountings for the front of the subframe so that the wishbone mountings are lower, at the front of the car. I think it would need a little more investigation before doing anything.

Meep, I am not sure how low you have your car but I can see that agressive camber is a problem for you, perhaps even too much? If you want the car to turn into corners sharply, maybe a bit more toe-out would be better, with less camber?

I think that the wishbones would be angled upwards at the outboard ends when the front is lower, and that would actually reduce the camber instead of increasing it. Have a look at where your wishbones are when the car is parked, considering the position of the joints at all three corners of the wishbone rather than the arm itself. If the joints are quite level then the camber would reduce as the suspension is compressed, because the bottom of the wheel would be moved inwards.

Pixs, I think that diving is only the result of weight transfer to the front as braking happens, and that weight transfer still happens even if the suspension is stiffer. I agree though, that the spring/damper would need to be solid to stop diving altogether. That is not a good thing to have for any other situation so we cannot have solid suspension. It is a compromise, a little stiffer suspension to reduce the diving but perhaps too stiff would make the car less stable anyway...

__MDC__