Ride Heights (Again)

[jjad]

Thanks so much for the photos Geoff, it is really clear in my mind now!

Cheers, Jonathan

 

[DavidN]

You have already answered your question, Malcolm...if you rotate the bar one spline at one end only, the ride height difference is great.

You are right too about the 3mm rule, so you need to rotate each bar by 6 to 10 splines, at both ends to achieve the desired ride height.
...

Guys, I don't get it. ops:

I tried to drop my F6 van on it's front about 2 to 3 Centimeters but had no luck.
My van has the "newer" style torsion bars without a lever to adjust the height so I had to mess with the splines.

I rotated the torsion bars one spline "lower" on their rear end which dropped the car waayyy to much. :eek:
(I was so shocked of the "lowrider-look" that I forgot to take exact measurements but it must have been about 6 to 7 Centimeters. ops

After that I rotated the torsion bars on their front end one spline in the opposite ("higher") direction.
(Rear end - one spline "lower" + front end one spline "higher".)
I ended up in gaining additional 6mm in height from where I initially started.

Can anyone guide me in the right direction how many splines (front end / rear end) and in which direction ("higher" / "lower") I have to turn the torsion bars to gain the 2 - 3 Centimeters of lowering?

That would be awesome !!!

Thanks,

David

 

[DavidN]

I just did an "as exact as possible" measurement and can provide some more data ...
I used Malcolm's Ride Height Sheet to do the measurements.

Before our attempt to lower the van we had:

H1 LHS: 271 mm
H1 RHS: 271 mm
H2 LHS: 245 mm
H2 RHS: 244 mm

After re-setting the torsion bars (1 Spline "higher" on the front side & 1 Spline "lower" on the back side of the bar) I have:

H1 LHS: 271 mm
H1 RHS: 271 mm
H2 LHS: 248 mm
H2 RHS: 247 mm

So we gained 3mm of height. :?

Can I assume that when setting the torsion bars 1 spline "lower" on the front side & 1 spline "higher" on the back side of the bar that the car would be 3mm lower then?

That would mean to lower it 30mm I have to set the bars 10 splines "lower" on the front side & 10 splines "higher" on the back side of the bar?
Is my thinking right here?

 

[Cornish4]

Hi David, it seems so simple doesn't it, move bar one spline and job done. Oh that it would be that easy. I wish to go the other way by about 5-7.5 cms all round, so I will be interested to see what our fellow forum members come up with before I tackle the job. I have been told by Derek Flavell of Renospeed in London that it is very much a case of trial-and-error, if you know what I mean.

 

[DavidN]

Okay, meanwhile I got really helpful information from some real experts.

The front torsion bars of the later models (models without excenter) have 20 splines on one end and 21 splines on the other.

Therefore it is possible to adjust the ride height by rotating the torsion bars the same amount of splines at each end in the same direction.

For 1 spline rotation you'll get 3mm difference in ride height.

For example:
If you rotate the LHS torsion bar clockwise (looking in the direction of travel) 1 spline at each end you'll gain 3mm in ride height.
(RHS torsion bar has to be rotated counterclockwise then.)

To lower the car by 30mm you'll have to rotate the LHS torsion bar 10 splines counterclockwise on both ends and the RHS torsion bar 10 splines clockwise on both ends.

Once you got it it is pretty simple, isn't it.

I'll give it a try and report back as soon as I can get hold of the special tensioner tool.

 

[Cornish4]

Hello David, when we had a go at adjusting the ride height of Marigold a while back it seemed that moving the front torsion-bar one spline in the bracket under the seat it raised the front by approx 50-70mm, unfortunately the back then looked a bit low, and as I load the car up a fair bit on trips at home and to France, I would like to raise the back too, by atleast 70mm. This is the part of the job I'm not sure of. The information you have posted is very informative though.

 

[DavidN]

Hello David, when we had a go at adjusting the ride height of Marigold a while back it seemed that moving the front torsion-bar one spline in the bracket under the seat it raised the front by approx 50-70mm, unfortunately the back then looked a bit low, and as I load the car up a fair bit on trips at home and to France, I would like to raise the back too, by atleast 70mm. This is the part of the job I'm not sure of. The information you have posted is very informative though.

Exactly what I figured - just the opposite way.
We initially changed 1 spline at the back of the front torsion bar which lowered my F6 van about 60 mm.

To set the ride height on the rear axle you have to pull out the rear torsion bars which is a hell of a job to do!

The rear torsion bars have 24 splines at one end and 25 splines at the other.
Rotating them per 1 spline (each end in the same direction) will adjust the height by 3mm.

Here's a diagram that shows how to raise the car by 18mm:

 

[DavidN]

Okay, as promised I follow up on my lowering project.

Below you'll find some before-and-after-shots ...

We lowered the car by turning the front torsion bars 6 splines on both ends from the original setting.
We did it as shown in the diagram I posted above but just the other way round.
(Diagram shows how to gain additional ride height.)

As turning the torsion bar(s) by one spline should make a ride height difference of 3mm, turning the bar(s) 6 splines should leave us at 18mm difference from where we started.
At least that was it in theory.

In the end (and after loosening and re-tightening all the front axle bushes to let them set properly) turning the bars 6 splines made a difference of 33 Millimeters.

Original setting was:

H1 LHS: 271 mm
H1 RHS: 271 mm
H2 LHS: 245 mm
H2 RHS: 244 mm

With 6 splines "lower" we have:

H1 LHS: 271 mm
H1 RHS: 271 mm
H2 LHS: 212 mm
H2 RHS: 211 mm

I hope these measurements will help anyone here to set their ride height properly!

Now I still have to do a front axle alignment ...

 

[iMacThere4iAm]

Glad you got the height you wanted in the end
I need to do some wheel alignment, so I'll be interested if you can take some photos as you go...

 

[Lobster]

Interesting reading, thanks. My F6 looks a bit high at the front and could do to come down a bit so thats food for thought.

Just need to pluck up the courage to do it now...

 

[Cornish4]

I noticed when we raised the front of Marigold she felt much softer on the road, especially over speed-bumps, much nicer to drive. So don't go too low Lobster. Once I get the back end up a bit, need to be a bit brave, I will raise the front again.

 

[Lobster]

It wouldn't be a massive drop, 20mm maybe. Just to stop it looking like a 4x4 really.

 

[Cornish4]

That's ok then David, didn't think you were going for a weed-cutter, leave that to those VW Splitty owners eh.

 

[Lobster]

No I did plenty of that when I was younger - Mk1 R5s that were very low coupled with uprated torsion bars and shock absorbers was a lot of fun although removing the rear bars was always incredibly hard work! I really should get round to scanning some pictures really.

I actually like the look of the VW buses that are lowered (and preferably with Porsche / Fuchs wheels too) but they must but terrible to drive.

 

[iMacThere4iAm]

I'm looking forward to raising Felicia up like a 4x4 but now's not the time...

 

[Cornish4]

I think a mildly lowered Vdub bus looks fine but go too far and the strain on steering joints, especially track-rod ends is too much. These buses are for showing only really, and as you say David not everyday drives.
I guess Tom before you do the 4L Trophy next year you will need to give Felicia a bit more ground clearance. I take it you are still hoping to enter the event.

 

[renault4mad]

Oh god.....dont get brian on the subject of raising suspension....

 

[Cornish4]

Between you and me Andrew is fighting shy of helping me do the work on Marigolds' back suspension, so I guess I will have to tackle it myself. I thought he likes a challenge, and there's me thinking he's a brother in arms.

 

[iMacThere4iAm]

That's right Brian, and I know how you feel about the 'raid' look... I reckon you should do one yourself and make it more than just a look

 

[Lobster]

Between you and me Andrew is fighting shy of helping me do the work on Marigolds' back suspension

Can't say I blame him - removing rear torsion bars was a horrible job 15 years ago, can't think I'd want to do the same now. I feel tired just thinking about it!