Talk Morgan Forums Morgan Sports Cars Morgan Three Wheeler & Super 3 Ground Clearance 5 Speed

I’ve discovered the ground clearance at the front of my car below the tubes that the number plate mounts to is only 110 mm. Furthermore the bell housing reduces that by another 25 mm or so and that’s before I get in! There is a scrape mark where the bell housing has bottomed out on at least one occasion but no other marks on the underside of the car. Is this normal for a 2012 car? To the best of my knowledge it has red spax shocks on the front which appear to be adjusted to their softest setting, with the lower wishbones parallel with the ground. the car is running on Blockleys at 22 psi. Comments, especially with regard to early models would be much appreciated.

Hi, Mine is pretty low too - but I like it that way. If you have red spax on the front, you know that you can adjust the ride height by doing up the big ring nut on each towards the top?

The lower wishbones are not normally parallel with the road, sounds as though your car has been lowered. If you have the steering comfort kit fitted this should result in the steering track rods being horizontal, are yours angled up towards the outer ends, if you haven’t the comfort kit fitted one way to correct the steering geometry was to lower the front of the car which then resulted in horizontal track rods again

The comfort kit raised the outer ends of the track rods by 50mm

My early 2012 car had bad bump steer under the standard setup. The steering rod arm angle down significantly.

The comfort kit remedies this. However some people like myself got the adjustable front shocks and lowered the front of the car until the steering rod arm was more horizontal and mitigated the bump steer. From memory approx 110 mm clearance at the front tubes

Possibly same for your car?

I have since then gone the comfort kit route and been able to raise the ride height by an inch or so.

I did this after using the front number plate as a road grader on an unsealed road. Quite a few of these in NZ at the more scenic spots!

Rog, u beat to it! Must type faster!! Lol

Like Rog G and P964 say, the important thing from a bump steer point is that the steering track rods are horizontal and you need to set the ride hight to get this. The early Suplex shock absorber equipped cars ran pretty low to achieve the horizontal steering arms and handled considerably better than the following Spax cars. The arrival of the Comfort Kit improved things for the Spax cars, although still far from perfect.

I do have to disagree with the assertion that the tie rod must be horizontal, as that is not at all the case.

What does have to occur is that at normal ride height, the 3 imaginary lines drawn along the upper A arm, the tie rod, and the lower A arm must intersect at a common point.

See the diagram below.

If that is the case, bump steer with be nil, regardless of the angle of the tie rod or control arms. Unless you are changing ride height significantly over or under the design ride height, then bump steer should be fine (assuming the steering kit has been installed on early cars). I should also mention here that changes to camber (which occur with ride height changes) and caster that require changes to the tie rod length to maintain toe can impact bump steer, but only if the length change is relatively large.

Fortunately for most owners the M3W suspension is not adjustable for camber and caster so it's hard to screw up. All this assumes you are only raising or lowering the ride height +/- an inch or so. If you are going say +/- 2" or more from stock then it would be worthwhile to check and adjust bump steer as required.




BTW-the diagram was taken from this article (https://www.onallcylinders.com/2014/06/27/correct-bump-steer/),

The M3W suspension in standard form is far from perfect and requires the Empire kit or similar modifications to get even close to your diagram. With it fitted Line 2 is achieved, as well as adjusting caster and camber. The Comfort Kit addressed some of the bad design and reduced the bump steer. All it did was raise the steering arms to a horizontal position and this seems to reduce the bump steer to an acceptable level, later cars had the Comfort Kit built in with raised steering arms on the uprights. In practise a horizontal steering arm, with a standard comfort kit set up, seems to be the best compromise. Although the standard suspension is non adjustable there are some quite large variations, even from side to side, particularly with early cars.

Quite agree Ian, the set up on my 2012 ( No 70) M3W had never been 100% to my satisfaction despite it having had a rebuild/new hybrid chassis in 2016.
A couple of weeks ago I had Craig at M3W Services Swindon fit a Black anodised Empire Kit.
What a world of difference it now is. I was well impressed with Craig's workmanship and the equipment he used to get precise set up of my caster/camber and toe angles.
I recommend this to anyone who's MOG is in need of it.
By the way I am still running the original Suplex shocks up front, they still do their job but i will evaluate if an upgrade would be of benefit. I have adjustable Spax at the rear.
Ian

Ian or others,

Are there any advantages to getting the Empire kit if one has the comfort kit already?

The bump steer issue was very bad on pre Comfort Kit cars (pre 2014 spec) but was considerably improved with the Comfort Kit and it's modifications were incorporated with post 2014 specification cars. I got the Empire Kit for my 2013 car before the Comfort Kit became available from Morgan. It sorts out about 90% of the poor geometry of the early cars suspension. I think if I had a Comfort Kit spec car from the start I would have been happy with that, it probably sorts about 70% of the problems.

The advantage of the Empire kit isn't as massive now as it was in the early days of M3W's. It does improve thing still and make the steering feel better to my mind and it allows you to set the steering geometry up correctly for caster, camber and track.