Talk Morgan Forums Community The Malvern Arms The pros and cons of sliding pillar suspension.

The TR chassis isn't particularly stiff even with the body fitted but will be better than a Morgan one. One must remember that the body will add some stiffness.

In bare form, you can lift each corner of the Morgan chassis a couple or more inches before any other corner lifts. Torsionally stiff it is not. However......

Believe it or not, the Morgan body adds a fair bit to the overall stiffness and the introduction by Morgan of the rear suspension hoop and scuttle roll bar increased the torsional stiffness considerably. In addition, the diagonal front cross-frame brace (anti-tramp bars) modification adds a lot more. This leaves the chassis between the cross-frame and bulkhead as the likely greatest point of flex.

On an unmodified pre-1990s Morgan, much of the compliance necessary for road-holding and handling will come from the chassis and body supported by stiff springs. On later and earlier modified cars, the additional stiffness will require softer springs front and rear.

I can't remember the lengths and poundage of the front springs that Dave Rutherford developed for me but they were based on the overall and individual corner weighs of the car as well as the desired ride height (lower). On the rear springs, the middle leaf was inverted; an old but effective trick for lowering and softening the rear.

So Morgan chassis and suspension design: an early 20th century blacksmith solution to early 20th century roads. It's quirky, odd, outdated and an anachronism but somehow it manages to deliver and entertain us. Just enjoy it!

Wirewheel, get your tin hat on; there's some 'incoming' heading your way I suspect!!!

Adrian, through TM I have learned about the 'stiction' issue and also have some experience from it myself - it gets worse when the lower bushing is worn and the upper bushing becomes an efficient 'brake' due to the pillar not being aligned. This is the reason why a went for the Vesconite Hilube bushings. From what I've read the Vesconite 'material' does not change it's friction properties under high pressure as bronze does and it certainly feels that way.
Now, I shouldn't really involve myself into any deeper technical discussion as I don't consider myself qualified. But, as a layman I can appreciate that the traditional Morgan chassis is not perfect and I could easily accept a change for the better. It's my opinion that such a change can be done within the present chassis concept. Here on TM there's lots of proof: new materials, structural enhancement, refined springing and damping, variable front end geometry etc etc.
I personally believe that MMC's future existence depends on their workmanship skills and the reputation it gives them and the pride it gives their customers - I think that's what many of us pay for, at least I am.
On the other hand a 'new' chassis could perhaps make the Morgan more competitive as a 'street car' - maybe a good thing market wise, but in my mind it has to be a true Morgan solution: a unique in-house construction in line with core values like simplicity, light weight and easy maintenance.
Then there's the money...
I love my traditional Morgan (with some refinement) for what it is and represents - to build a new 'tradition' will certainly take some time.

"core values like simplicity, light weight and easy maintenance."

I'd agree with most of that line, except the light weight. Sadly Morgan are still making cars with the mentality of a blacksmith, ie, if you want it stronger, use thicker and heavier material. The Three Wheeler is a classic case in point, and could have been a perfect opportunity to break away from their blacksmith in residence.

Very interesting discussion about sliding pillar, is there a reason that the factory haven't adopted the Suplex and/or Mulfab remedies in production? Clearly they give a huge improvement.

Please forgive my ignorance, perhaps I'm confusing the chassis weight with the over all weight (which I consider quite low...)
Please correct me (again) if I'm mistaken

Not your fault Thomas, having had a lot to do with Caterham Sevens in the past, I just don't have much faith in Morgan to be careful or even know how, to build strong but light cars. The Trad at around 1000kgs is only relatively light, my old Caterham 21 was around 750kgs, same as an early Elise, so surely a trad could be around 800kgs if they tried, and the Three Wheeler at over 525kgs dry is at least 75kgs too heavy.

The problem with the Morgan front suspension is not only stiction; it is distortion.

Imagine this: a fabricated stub axle made from a casting with two steel tubes welded on to it through which a 1" kingpin supports the stub axle with springs either side.

Then consider the sideways forces exerted on the outside wheel. This will distort both the stub axle and the kingpin. Result: lock-up of the the kingpin/stub axle assembly.

Bearing material will not overcome distortion.

This is exactly what I was badly trying to get across. Very well put

Something that has occurred to me since starting to Hillclimb the MR2 and strip it's suspension to replace the worn out bushes is how this relatively simple design which is completely adjustable might be applied to a Morgan front and rear. If coil over shockers were utilised to reduce height then these could be attached to a modified front frame and brackets simply attached to the chassis for swinging arm, with front trailing arm similarly mounted. The rear would need careful thought for design. Just a thought!

Adrian, beware! You are one small step away from convincing yourself that competing in a Formula Ford or some other single seater is just the thing.

If you do, you will start to realise how adjustable a race car's suspension really is and how corner weights, ride height, spring poundage and camber, castor, ackerman and all sorts of other geometric delight will hold in store for you!

Tempted? You may and should be with your interest!

BTW, I also sprinted a Van Dieman RF84 FF1600 and Royale RP3 FF1600.

I hear all the arguments...but am not sure they are really valid.

Why?

Most of us own and enjoy Mogs because of their idiosyncratic semi-vintage characters. Remove them all and you have a pastiche of a 1950s car.

The chassis is a joke, as far as stiffness is concerned, so it is part of the suspension. The suspension, well it works but can never do the job of a modern system.

If you want a car with a modern chassis that looks like a Mog it will cost you £85K. It is called a Plus 8. I'm sure MMC would put a +4GDI engine in the Aero chassis if you paid them, but who wants to pay £80K for a 6 foot wide +4 with a modern tub and suspension? Better to buy a nice little Lotus...

No, the trad Mog is what it is. Flawed, yet a delight.

Rather like many of us here....