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Re: Mmmm The handling still needs work.
No life (a.k.a. DattoMaster)
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The reason for mid corner change, most notable in the middle of turn two, is I'm breathing the throttle to get the car to rotate back into the second apex. Same thing in turn one. I'm not making any steering corrections, as I said in the early post I steer with the pedals. In fact many of guys are taken aback by the fact that I'm drifting the car and making hand signals at the same time. As you know loads of opposite lock scrubs speed.

So I measured the end play tonight and I've got as much as .008" if I'm measuring this right. I'm grabbing the backing plate with my fingers and pushing in on the axle flange with my thumbs, that results in 3-4 thou. Then I put my fingers behind then flange and thumbs on the brake shoes and pull out this results in 3-4 thou the other side of the 0 on my dial indicator. So 6-8 thou total. I just did the driver's side but I'll assume the it has the same issue. So basically I've got near 1/4 millimeter of slop in there. I will add another shim behind the bearing to get it in spec.

Posted on: 3/13 4:53
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Re: Mmmm The handling still needs work.
No life (a.k.a. DattoMaster)
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Well with so many exclusions even reading back through i cant tell what we are actually supposed to be looking at or analysing anymore???

What is the issue?

Posted on: 3/13 12:26
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Re: Mmmm The handling still needs work.
No life (a.k.a. DattoMaster)
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Sorry for the thread being so convoluted, so for clarification purposes;

Post 1: first video current wayward handling.

Post 4: second video shows non-functioning right rear shock due to top mount coming undone, the car weaves but has an up and down motion to the oscillation dissimilar to the video in post 1.

Post 8: video of car pre-oscillation issue, same exact set up but with H145 rear end, problem started with the install of the H190.

So to surmise; first video shows current issue, second video shows what it looks like with no damping, third video shows how it was before this issue. Binding tends to be snap oversteer / opposite lock, car weaves all by itself without any steering correction. So Id say no binding. The car behaves & feels different now versus known condition with 0 damping. So Id say shocks not likely cause.

The left side rear axle has 6-8 thousands of end play (havent checked right but expect the same).
So the question now would 16 thousandths / 1/64 of end play cause the car to weave back and forth as it does in the first video?

If Im visualizing this correctly; in a corner the outside axle would push in and the inside axle would pull out, the rear track would be 1/64 inside of the front track. The rear would move toward the outside to correct the dog tracking, this would cause oversteer / rear steer, which intern would lower the lateral force which may in turn cause the axles to move again, hence the tank slapper.

This vigorous back and forth action also likely explains the bizarre wear pattern on the rear tires.

In a previous post I noted the inside edge of tires looked like someone took a woodworkers gauge to the inner most tread block.

Posted on: 3/13 18:57
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Re: Mmmm The handling still needs work.
No life (a.k.a. DattoMaster)
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I'm no expert but the scale of this issue is surely far too small. 1/4 millimeter. Tyre side walls will deflect say 15mm millimeters and nothing but bushes locate the entire rear end allowing probably another 25mm . I cant believe what your mesuring could do it. Although the tyre wear is indicating something.

If you can move the axle with your fingers that sounds odd. The bearing is pressed on the axle and it normally takes a hammer to drive them in or out. Any movement by finger force would be within the wheel bearing itself or the wheel bearing has moved back and forth enough to wear a clearance in the housing?

Could it be a stuffed wheel bearing?

Posted on: 3/13 20:07
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Re: Mmmm The handling still needs work.
No life (a.k.a. DattoMaster)
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Yes I can pull push it by hand. With the rear suspension in full droop , the wheel and drum off, it will just be the weight of the axle.

The bearing is sliding back and forth in the housing. It did it much worse than this before I shimmed it the first time.

The bearing could indeed be stuffed; once I actually pull the axle I'll know for sure. Given the number of miles put on the car and the fact that the bearing is for a car that's 200 Kilos heavier you wouldn't think so.

The wheel bearings in the H145 had been on the car for 15 years without issue...........of course that doesn't mean jack either.

Posted on: 3/13 20:53
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Re: Mmmm The handling still needs work.
No life (a.k.a. DattoMaster)
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I measured the right side and I'd say problem found; you can actually see the play it moves almost 20 thou, add that to th 6-8 thou and you have near 3/4 of a millimeter, which is pretty near a 1/32".

If this isn't the issue its surely a large part of it.

Now I just need to get a motor back in it. I won't know until my next event with the car in mid May.

Posted on: 3/14 4:47
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Re: Mmmm The handling still needs work.
No life (a.k.a. DattoMaster)
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no way less than 1mm play in wheel bearings is causing that.

bottoming out will certainly cause snap oversteer, a gradually increasing bind situation like you might get from a traction arm length conflicting with elongating spring length isn't the same thing though.

I've never seen a leaf sprung car behave like that. Somethings fundamentally wrong with the rear end, and it's not just 0.030" of bearing play.

Posted on: 3/18 23:16
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Re: Mmmm The handling still needs work.
No life (a.k.a. DattoMaster)
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Harry it could well be. Regardless I need to get the end play back to spec.

It really doesn't feel like it's binding at all. While it does look like snap oversteer, from the driver's seat it's really not. I'm not having to make big corrections on the wheel.

I totally agree that I've never seen a leaf spring car that frequency weave.

My next event with the car is in May. Between the end play and the new dampers I'm hoping it will be solved. I also am going to try discounting the rear bar to see if that is somehow causing this.

Posted on: 3/20 2:53
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Re: Mmmm The handling still needs work.
No life (a.k.a. DattoMaster)
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Is it possible to floor pan is touching the diff housing at the third member and pivoting, under high load conditions. The H190 housing is physically larger [taller] than the H145/H165 housings.

Posted on: 3/20 3:45
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Re: Mmmm The handling still needs work.
No life (a.k.a. DattoMaster)
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Benny it's possible but there are no obvious marks. When I first installed it I was concerned about that and checked. I also checked when I was under the car installing the new bushings.

Posted on: 3/20 4:27
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