Author Topic: Torsion Bar Adjustment - I know ... its been explained many times  (Read 479 times)

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NSharpley

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I'm across all the Haynes manual info, ie. 1 spline = 1.5mm ride height, etc.

My issue is I cannot seem to get both sides the same.

I am initially measuring from the lip above the bottom ball joint to wheel arch.

I've set one side, the gap is 640mm.

On the other side I move between 625mm and 685mm with one sline movement.

It doesnt seem to matter what I do, move a spline at both ends of the torsion bar or just one, I end up with around 60mm change.

I'm after that 640mm on both sides.   

Current Alfa:
1975 Alfetta GT 2.0 Race car

Past Alfas:
1989 Alfa75 2.5ltr
1982 Alfetta Sedan 2.0
1976 Alfetta GT

sportiva

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Re: Torsion Bar Adjustment - I know ... its been explained many times
« Reply #1 on: December 04, 2021, 09:26:30 AM »
The torsion bars have different numbers of splines 34 front and 35 back. Based on the 1.5mm per spline formula, If you remove the whole bar and rotate it 16 or 17 splines at both ends either clockwise or anti clockwise, it should bring the height difference into the 24-25.5mm range.
« Last Edit: December 04, 2021, 09:38:19 AM by sportiva »
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ex
75 2.5
2.0 Alfetta Sportiva #22
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bteoh

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Re: Torsion Bar Adjustment - I know ... its been explained many times
« Reply #2 on: December 04, 2021, 02:15:34 PM »
The way I do it is to measure from the ball joint to a reference point on the wheel arch , say you have 640mm. Then secure the lower wishbone to that height and rotate the torsion bar till it slips into the splines easily. Easier to do than counting splines. Good luck  :)

NSharpley

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Re: Torsion Bar Adjustment - I know ... its been explained many times
« Reply #3 on: December 04, 2021, 03:03:07 PM »
The torsion bars have different numbers of splines 34 front and 35 back. Based on the 1.5mm per spline formula, If you remove the whole bar and rotate it 16 or 17 splines at both ends either clockwise or anti clockwise, it should bring the height difference into the 24-25.5mm range.

Its like an awakening!

All sorted now.  I understand the process now.

Thank you.
Current Alfa:
1975 Alfetta GT 2.0 Race car

Past Alfas:
1989 Alfa75 2.5ltr
1982 Alfetta Sedan 2.0
1976 Alfetta GT

NSharpley

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Re: Torsion Bar Adjustment - I know ... its been explained many times
« Reply #4 on: December 04, 2021, 03:05:35 PM »
The way I do it is to measure from the ball joint to a reference point on the wheel arch , say you have 640mm. Then secure the lower wishbone to that height and rotate the torsion bar till it slips into the splines easily. Easier to do than counting splines. Good luck  :)

That would work if I had torsion bars that could move rearward through the bridge, like standard bars.

Mine are 28mm and wont move through.

I watched a YouTube vid where they did the adjustment that way.  Such an easy option with smaller bars.  But wouldnt work for me.

Counting splines, albeit tedious, works.

Current Alfa:
1975 Alfetta GT 2.0 Race car

Past Alfas:
1989 Alfa75 2.5ltr
1982 Alfetta Sedan 2.0
1976 Alfetta GT