Discreet but capable

sniper wrote: Lengthening the drop links will reduce tension on the arb and soften its input.

Shortening (which is what has happened because of the lift) makes rebound sharper and can cause a cross axle wobble if severe.

By moving the bottom mount up or down, you increase or decrease the preloaded torsional tension that the anti roll bar is under. This can vastly alter spring across the axle, easier to understand as rebound. Hit a pot hole on one side and get a jump from the other side in rebound.

sniper

Err how. The bar is free to rotate in the bushes at the chassis end so if both ends of the return arms drop equally as when the suspension is unloaded then the bar is under no tension and offers no resistance to movement beyond any friction from the bushes. If one side of the axle moves vertically relative to the other the bar attempts to match that movement in the opposite wheel but that is via the integral spring strength of the bar being put under torsional load along the axis parallel to the axle. The only way to alter that is either a thicker stronger bar or to change the leverage ratio of the return arms. If the arb was physically through bolted into the chassis that would have the effect you're after but that would make it a torsion bar like the rear suspension on a Peugeot 205 but that's not how it works.

The arb is fixed to the hub at each end by the drop links, in a static position there is some preload. That preload can be adjusted by increasing or decreasing the length of the drop link. Shorter will increase the load and encourage a more positive response, longer will reduce the load and soften the response.

When they are too tight they can cause the car to pitch from side to side, the arb just acting as a spring and not absorbing (torsionally) any of the roll, maybe even exaggerating it.

My axle is 30-40mm further away from the arb, this has changed its preload (increased) and its speeded it's response.

As I originally stated, I might be able to tune the bounce out by increasing the damping rate. I don't want to go too hard though, so if I can't quieten the bounce with the dampers, I will have to increase the length of the drop link with adjustable units.

sniper

:laugh: :laugh: :laugh: :laugh: :dry: :laugh: :laugh: :laugh: :laugh: :laugh: :laugh: :laugh:

I LOVE THIS ,,,,,,,

I'm not clever enough to get this on paper but a short browse found this If you're interested.......

"Whiteline are well known for producing adjustable anti-roll bars and these have a number of holes formed in the end of the bar which enable the drop link to be unbolted and then moved. This changes the lever length of the anti-roll bar. If the lever is shortened then the roll stiffness increases, conversely if the lever is lengthened, the roll stiffness decreases. When purchased in kit form, heavy duty adjustable drop links are often included making it a complete package, however many anti-roll bars sold do not come with drop links, and you are expected to use the original equipment link on the car. Most of the time these links are adequate. Certainly they are from the original equipment manufacturer. Unfortunately in the aftermarket there are often cheaper alternatives which don’t last as long. If you take a design that is weaker than the original and then put higher loads through it, you can definitely expect lost rate and there’s a very good chance it might break. There is also the likelihood to wear the bearing more quickly and cause knocking if it doesn’t break it.

It is useful to consider the loads we’re dealing with. Lets imagine a 3 foot wide bar with 6 inch levers. If this was 1 inch in diameter it would create 834 lbs roll stiffness for each inch of movement. What happens if we move the lever point just 1 inch? Making it 1 inch longer brings the stiffness down to 605 lbs / in and shortening it by 1 inch increases it to a mighty 1218 lb/in. If we imagine that the original bar was just ¾ inch thick and had a fixed 6 inch lever it would have given us just 264 lbs of roll stiffness. So it’s easy to see that by running a larger diameter anti-roll bar and running it in the stiffest position, the drop link has to cope with massively increased loads.

Another factor with drop links connected to adjustable anti-roll is that as the bar is adjusted the angle of the drop link will change. This means that the load will no longer be solely in the intended orientation (which would be North – South as you looked at a link). Instead the drop link would now be receiving loads at an angle which will put the ball joint under more stress. The solution to this is simple as Whiteline supply a range of adjustable drop links. This means you can get the link adjusted to the correct length, to ensure the loads are received in the correct plane.

So there you have it, adjustable drop links that are uprated are not just for show. They enable you to set the length of the link to ensure the load is carried correctly, and set the length of the link to ensure there is no preload. In short they are an essential part of anti-roll bar performance and worth seeking out where adjustable, uprated versions are available."

I don't think I can add anything to that, I hope it clarifies adjustable links and the need for them.

sniper

So the car will be as it stands for some considerable time now, future plans are all engine and drivetrain related therefore expensive.

Unless the finance fuhrer decides she wants a world cruise and feels so guilty she throws a couple of grand at me..... they might well stay as plans.

05' VVT with 74000 miles

Body - Standard apart from a nice textured paint job (scratched a bit), rear seats / panels removed, Sony bluetooth stereo/speakers

Engine - Mobil One oil, new sump pan, K&N filter, Yuasa battery

Gearbox - New Luk clutch, fully synthetic oil

Transfer Box - Replaced with a low mileage used box, fully synthetic oil, Jimnybits guard

Suspension - AVO adj dampers, Eibach +30mm springs, 15mm Superpro spring seats (25mm o/s/f), Polybush castor correction and panhard bushes, Superpro anti roll bar mounts

Rear Axle - New wheel bearings, Quaife ATB differential fitted at M&T Transmissions along with a full rebuild, fully synthetic oil, shock repositioners,

Front Axle - N/S/F wheel bearing, kingpins, bearings and seals, new callipers, drilled/grooved discs, AVM HP manual hubs, greenstuff pads, Hel braided lines, fully synthetic oil, Jimnybits Rough Country steering damper

Tyres - BF Goodrich All Terrain KO2's in 215/75x15 with 30mm spacers


So far so good, it's a cracking little car but I have spent a mortgage on it. Sadly the spanners and welders are beyond me these days and I have to pay to get my shiny bits fitted. Hence the finance fuhrer's recent change in attitude, she flipped when I told her what I'd spent on the diff rebuild.

I'm going to set about having some fun in the car with more green lanes, possibly an RTV trial (if I dare risk my bumpers) and some longer journeys around Scotland and Ireland (apparently holiday budgets are nigh on unlimited....).

I'll be seeing a few of you guys along the way too, thanks to the forum.

sniper