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[05omegav6]

Longterm replacement for the rear bush together with better steering response

I know Chris is not convinced, but with poly fronts fitted, pattern rears only last about 20k. Once bolted on, balljoints are a doddle to change, with no set up required.

[feeutfo]

The situation is different on a shopping front wheel drive car, though. You have the forces from the driven axle to control so there isn't the luxury of allowing some "give" in the bushes to compensate for cornering, etc. or it'll torque steer all over the place.

What problem are we trying to solve with the original bushes? IME they have very much less "give" in them than the front bushes and, again IME, they don't seem to fail as quickly.

A bit more accuracy, although a vast majority if that problem can be removed by fitting tyres that actually work, and life span.

My lemforders rears are two years old and no splits or seperation, but whilst removed for some poly experiments, I clamped the bush In a vice and tested the resistance by levering/pulling the wishbone. Far from scientific but they are quite loose.

So some improvement in longevity would be nice.

But I've just purchased a 10 ton press, so no worries here really. I just would be nice to fit and forget.

[Marks DTM Calib]

Note that ten ton is borderline for pressing out the front bushes 

More than enough for the rears, a good vice will do those.

[feeutfo]

Note that ten ton is borderline for pressing out the front bushes 

More than enough for the rears, a good vice will do those.

Yes iirc I've seen 11 ton on this press, if the gauge is akawut.


Or cut the fe@kers out is probably just as easy now.


... Got press me.

[2woody]

Hmmm, I presumed the only reason the rearward bush is vertical is to give yaw movement given the excessive play the front oe bush can give throughout its life?

No - I'm sure its part NVH and part handling.......

Lots of NVH research points to a loose wishbone front-to-rear being the most important thing for comfort. Well, actually the hub centre being free to move a bit rearwards under bump deflection. That's part of what GM will have been trying to achieve.

From the handling side, what you really need is some automatic toe-in when cornering. This has the effect of gaining more turn than the driver thinks he needs ( or better handling to put it another way ). This is achieved as follows .......

under cornering, the outside wheel is more loaded than the inside one. The floppy vertical bush allows the wishbone to move rearwards ( see above ) It also allows the wishbone to move inwards at the back. Now think of what's happened to the outer ball joint - its moved both rearwards and inwards. Compare this to the steering tie-rod, which doesn't flex at all - you get bottem ball joint in and rearwards and steering knuckle unchanged, hence the wheel toes in slightly.

( don't even think that I came up with this one - it was down to a good mate of mine who just happens to be chief suspension designer for xxx )

[05omegav6]

If the rear bush is too soft or worn, then the front wheels toe in at the first sign of ANY load

[TheBoy]

On TBE, I've been struggling to get GM rear wishbone bushes to last more than 12-15 months - which is next to frak all in mileage terms (5 or 6k max)

[VXL V6]

On TBE, I've been struggling to get GM rear wishbone bushes to last more than 12-15 months - which is next to frak all in mileage terms (5 or 6k max)

Just wondering if bigger wheels with lower profile tyres and stiffer springs is accelerating the failure timescale?

[TheBoy]

Possibly, Silver Bullet's have been in ages now (about 6 months before the homemade press got broken at Newent)...  ...although TBE has had front polys in for longer...

[2woody]

undoubtedly

[feeutfo]

Stiffer suspension= less suspension travel=less wishbone movement= less stress on bushes to my mind. Poly giving less yaw too.

The rear bushes fitted at Newent where Meyle heavy duty. NOT Gm. NOT lemforder. Iirc...?

TB where Rusty Bullets bushes Meyle or Defo Gm..?

[feeutfo]

...and how long did the failed bushes spend on Elite suspension? ...with an enthusiastic driving style...?

[feeutfo]

For example, TBE doesn't roll around like this particular Elite any more

[05omegav6]

That front seat passenger looks about as impressed as Mrs TB

[Kevin Wood]

For example, TBE doesn't roll around like this particular Elite any more

What? Even when full of salad-dodging journalists?