Bit odd at speed?

[andy198712]

Hello!

Hard to discribe in the title so here goes

1972 standard beetle.
Front
HD roll bar
Kyb gpr shocks
Stock height
Stock Camber nuts wound in to give max neg camber
Tyre are 175/65/15 on empi 8's

Rear
Swing axle
195/55/15 empi 8's
Stock shocks (was too oversteery in the wet with gpr's on the back too)
Stock height (has positive camber at rest and thinking this isn't helping)


I used to have a camber compensator on it but took it off when I changed to 1500 box.

It was a 40hp so maybe I just havnt realised it much as I didn't really travel at speed much over 50...

But now it has a 2110 I'm noticing it more.

Any advice?
The long term plan is koni's all around and lower it but I have a big deep sump on that worries me.
Its a daily driver too.

Slow speed its great!
But higher speeds it feels a little unstable when I turn in, like it was to turn in more then I ask... Maybe it's the softer rear? Or pos camber or high CofG? Just doesn't feel stable...
In a straight line its good at reasonable speeds, and good on rough roads (no bump steer)

Thanks for any input, hopefully I described it ok?! It's a odd feeling! Kinda over sensitive?

[PhillipM]

Check the rear toe setting. Sounds like not enough toe-in.

[andy198712]

Ok thanks I'll measure that at the weekend it does feel like the back tryin to oversteer but not...

[Piledriver]

Did it have a factory Z bar?
If so it came with softer rear bars to compensate for it in bump.

Air pressures also have huge effect, we used to get a question about 3x a year about cars with new tires and horribly twitchy steering at speed... The tire shop folk don't realize T1s should have lower front pressure.
(wheel/tire and suspension mods effect how much, but factory recommended was 18F/28R or in that range)

[andy198712]

How do I tell if it came when new?
Yh I agree on the pressures! I normally set to factory spec or plus 2psi

Cheers

[Piledriver]

How do I tell if it came when new?
Yh I agree on the pressures! I normally set to factory spec or plus 2psi

Cheers

I thought that all swing axle beetles after ~67 or so had it as std?
The camber compensator prevents the inside tire jacking but toes AFAIK not soften the rear end in roll.
(68+ is USA were all IRS, so Z-bars are rare as hens teeth here)

Both reducing rear roll stiffness and anti-jacking are desirable features on a SA car...
Perhaps use both ? (have never personally had a car with either, had a 64 Ghia, 66 bug (pre-Z bar) and rest were IRS)

The bodies (Even the IRS cars) all had the mounts in the rear inner fender area, hole is about 30mm, with 2 holes or studs to actually mount the Z bars bushings. Check for variations in the paint?

Actually installing a Z bar would soften the rear up in roll, reducing oversteer (that's why it exists)
Its actually tunable by playing with the free play in the bushings.

[Dan Dryden]

Sounds a bit silly, but just go around all of your suspension and check all the nuts and bolts are tight.
I had a problem with the front of my 1302 feeling like it was trying to fall over itself during high speed cornering.
Embarrassingly, I found a couple of the lower strut mounts had worked loose!

[buildabiggerboxer]

Sound advice Here ^^^^^^, Also Stock rear ride height is the first stop for the big camber adjusting hammer on swing axle cars, bring it down one outer spline and it will be a night and day improvement, 30* toe in is all it needs, the usual bushes sermon applies.
European 1200 models had no z bars fitted, blank rear 1/4 moon vents identify 1200's, In my view they are overrated anyway on the circuits, there are better ways, but they can work well on the street with stock tb's if shimmed to work full time as above, they promote under steer and help traction out of tight turns, as I said, not what you want on the race track, but safe for the street.
If you are fighting the car on straight but undulating bits of road, or odd steering inputs needed when braking hard or hitting the loud pedal, it's likely you have bump steer, and you will need to address this.

[Dale M.]

As for handling, if front end is twitchy think of what you have on rear for anti roll/sway bar... If rear is twitchy think about what you have on front... Sounds silly but anti-roll/sway bars have big influence on how handling is on "other end of car" ("Chassis Engineering" by Herb Adams).... On both my fiberglass buggies I had heavy duty anti-sway bars front and rear, and car handled pretty flat, but once it got loose you (hard race track type cornering) were sort along for the ride till car decided to give control back to you.... Also ran some where between "0" and 1/16 toe in on rear of buggies but buggies all handle well up to about 80+ MPH and it was sort of "just to fast" considering....

Dale

[Ol'fogasaurus]

Andy, by any chance do you have off-set wheels in front? If so this could affect the steerig (camber change).

Lee

[Slow 1200]

what's your front toe set at? with negative camber the stock setting doesn't necessarily work, also what about the caster?

[andy198712]

Sounds a bit silly, but just go around all of your suspension and check all the nuts and bolts are tight.
I had a problem with the front of my 1302 feeling like it was trying to fall over itself during high speed cornering.
Embarrassingly, I found a couple of the lower strut mounts had worked loose!

Not silly at all, I chased a knock for ages and turned out to be the top and bottom rear shock bolts mixed up! Mean one would tighten and stay loose

[andy198712]

Sound advice Here ^^^^^^, Also Stock rear ride height is the first stop for the big camber adjusting hammer on swing axle cars, bring it down one outer spline and it will be a night and day improvement, 30* toe in is all it needs, the usual bushes sermon applies.
European 1200 models had no z bars fitted, blank rear 1/4 moon vents identify 1200's, In my view they are overrated anyway on the circuits, there are better ways, but they can work well on the street with stock tb's if shimmed to work full time as above, they promote under steer and help traction out of tight turns, as I said, not what you want on the race track, but safe for the street.
If you are fighting the car on straight but undulating bits of road, or odd steering inputs needed when braking hard or hitting the loud pedal, it's likely you have bump steer, and you will need to address this.

Yep I own a 1200 so no rear z bar
Drop it one click on the rear, got it. Will check the rear bushes when I do, and measure them for reference.
Is that 30minutes? Can I check that with a tape measure? We have the kit at my car club but might be a while....
No bump steer, handles well in a straight line and over bumps ect which is a plus

Cheers

[andy198712]

Andy, by any chance do you have off-set wheels in front? If so this could affect the steerig (camber change).

Lee

I'll find out the ET and report back

[andy198712]

what's your front toe set at? with negative camber the stock setting doesn't necessarily work, also what about the caster?

I'll measure it and find out