Rear suspension height

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Steven collins
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Rear suspension height

Post by Steven collins »

Checked the car over this morning and noticed that the
O/S rear has dropped by nearly an inch in height compared to the N/S and is quite noticeable from behind (to me anyway)
Could this be due to the parabolic springs or the shock absorber?
Springs “looks” the same as the N/S but I’m no expert!!
When pushing down on the rear wings N/S seems “firm” O/S feels weaker but both “bounce back” about the same amount.
Any help/ideas would be greatly appreciated.
‘66 MGB
Many thanks.
Ian F
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Re: Rear suspension height

Post by Ian F »

I don't know anything about parabolic springs - are they the same, drivers side to passenger side?

I would disconnect the shock absorbers ( original or telescopic?) and check the ride height from bottom of chrome strip to centre of wheel. These should match and measure 13.5" -14.0".

Ian F
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1972 BGT, Blaze, Navy trim, recessed grill
1961 Midget, 948cc, now sold
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Steven collins
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Re: Rear suspension height

Post by Steven collins »

Hi Ian, the springs look equal to each other side to side, so I do suspect the shock absorbers, they are the original type probably been on the car over 20 yrs 😳
Current measurements are as follows:
Front
O/S. 13”
N/S 13.1/4”

Rear
O/S. 14. 3/4”
N/S. 15.1/2”

from bottom of chrome strip to centre of wheel.
Ian F
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Re: Rear suspension height

Post by Ian F »

The rear does look a bit on the high side, but I don't know if that's what parabolic springs should be like.

I would disconnect/remove the shock absorbers and measure again. The lever arm dampers shouldn't really affect the ride height, at least not in a standard set up. They should sit somewhere around halfway through their arc of travel when at rest.

Some telescopics can exert a "push" on the suspension, but I don't believe lever arms can

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1961 Midget, 948cc, now sold
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Steven collins
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Re: Rear suspension height

Post by Steven collins »

Thanks for the extra information it’s much appreciated, cannot get to the car for a few days now due to family issues but will let you know how I get on once I’m able.
Thanks again.
Not_Anumber
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Re: Rear suspension height

Post by Not_Anumber »

Have you got any further with it ?
1979 MGB GT
1999 Jaguar XKR
2003 MG TF
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Steven collins
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Re: Rear suspension height

Post by Steven collins »

Sadly not been able to get under the car yet but as soon as I am able I will keep you updated on what I find and what the remedy is (at the moment it feels like an itch I cannot scratch, will be glad to get it sorted)
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Adrian Oliver
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Re: Rear suspension height

Post by Adrian Oliver »

Shock absorbers have no effect on ride height whatsoever.

They are purely there as a damper of spring action.

Perhaps the rear springs have been tempered differently?

If you transposed the left to right and right to left you would know.
1962 Chelsea Grey MGB
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