Front end lowering

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WalkerContracts
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Front end lowering

Post by WalkerContracts »

Does anyone know how to lower the front end of a split screen morris minor?? i know they have torsion bars but didnt want to touch them before gtting some advice on how to do it. Aswel with lowering does anyone know how to stiffen the front suspension as mine is very soft, i thought of putting heavier oil in the dampers but will this work?? I seen front shock absorbers kits on a parts website, would these make much difference? sorry for all the questions but any help would be great, thanks everyone
leyther8008
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Post by leyther8008 »

Theres a vernier plate at the reaction ends of the torsion bars that give you a little adjustment, or you can reset the torsion bars by 1 spline which is supposed to give you about an inch and a half drop, there are stronger torsion bars availiable from specialists and theres always advice on what oil you can put in the lever arms to tighten them up.
I'll see you on the otherside'!
MoggyTech
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Post by MoggyTech »

The Morris Minor was designed with neutral suspension position with the car unladen. 60mm up 60mm down = 120mm total suspension travel (limited by upper and lower bump stops)

If you lower the car too much, you risk the suspension bottoming out, unless you increase suspension spring rate by adding stronger torsion bars, and or coil over shocks. If you simply lower the car without stiffening up the suspension, you risk mashing the inner wings, as the top trunnion hammers into the bump stop.

Some folk use engine oil in the dampers, but if you do this, check the damper mounting bolts to bulkhead are tight and in good condition.

FWIW I run with 1/2" lowered at the front with the valves removed from the dampers, and Gas Dampers Mod Kit fitted. This gives added safety, as a worn lower trunnion cannot be ripped off the kingpin, as the Gas Dampers act as a brace link that limit suspension movement beyond +5mm in either direction from maximum. Combined with 185/60/R14 tyres, the ride is pretty smooth for a Moggy :D
bmcecosse
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Post by bmcecosse »

It is lowered by simply moving the front suspension arms on the torsion bars - but why would you want to lower it ?
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downsey
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Post by downsey »

but why would you want to lower it ?
because it looks way nicer lowered
bmcecosse
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Post by bmcecosse »

Not everyone would agree! If you MUST do this - take note of what's been said already - you will have no worthwhile suspension travel, the front uprights will smash the inner wings, the suspension arms will smash the tie-plates (and wrench the eye-bolts through the front chassis members) - and if you lower the rear too much, the rear axle (assuming the bump stops have been sacrificed to get the car low) will smash the 'chassis' rails and the car will effectively start to break it's back. If you really want a low-rider car - you will need to engineer it properly.
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jonathon
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Post by jonathon »

Its quite acceptable to lower 1 spline, (about 11/2") on the torsion bars with no adverse effect on the action and safety of the suspension. You must cut down the top bump stop by a half and ideally uprate the torsion bars by 30%.
Lowering the rears by blocks should really be done by weldin on the correct axle perches for the desired amount of drop, rather than by adding lowering blocks, again you will need to reduce the bump stops by a half.
Last edited by jonathon on Wed Nov 07, 2007 10:01 pm, edited 1 time in total.

bmcecosse
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Post by bmcecosse »

At one spline down - unless stiffening the spring rate and/or beefing up the damping - the car WILL damage the shell on heavy bumps/landings. I assume it's the rear bump stops to be reduce by half ?
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Kevin
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Post by Kevin »

I think Jonathon reply say it all as he does build adjusted Moggies :wink: for a living.
Cheers

Kevin
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jonathon
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Post by jonathon »

BM , well spotted, just keeping you on your toes. Actually lowering by one spline will not cause any damage through contact, any more than at standard ride height. As I said uprating the torsion bars will help and obviously a gas damper kit will further improve the situation.

bmcecosse
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Post by bmcecosse »

Cutting down the bump stop will allow serious contact/damage (and you lose the 'progressive' effect of the taper nose on the bump stop!) - I agree completely - if doing this then some spring rate changes will be necessary - be they uprated bars - or coil spring 'helpers' or even complete replacement coils.
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jonathon
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Post by jonathon »

But cutting down the bumpstops in effect gives you the same amount of travel, and only potholes or driving up kerbs will induce the kind of excessive travel that you describe. A well set up car will produce between 1" and 11/2" of travel in normal road use. Might just be those Scottish roads or your liking for rallying :D :wink:

IslipMinor
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Post by IslipMinor »

On a lowered car, cutting down the front and rear bump stops is essential, otherwise you end up riding on them. After cutting them down, they need to be reshaped to retain the progressive profile - an angle grinder makes very short work of it!
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downsey
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Post by downsey »

I have my car lowered 1 spline and the lowest setting on the vernier plate and my front suspension works great. Unless you hit a speed bump doing 60, i dont think anything would break.
Peetee
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Post by Peetee »

Might I add that its vital to ensure your car has factory-spec ride height before you start. It's a recipie for disaster if you do what has been recommended to a car that has tired suspension.
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jonathon
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Post by jonathon »

Good points Peetee :wink: :D

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