Talk Morgan Forums Morgan Sports Cars Classic Morgans (pre-CX) Roadster 5 link rear suspension re-visited

I fitted the SSL front kit many moons ago, and have been very pleased with the results. The only real issue for me is the need to keep adjusting the ride hide to get the optimum setting at regular intervals, say each service.

Last year I fitted the 5L rear and although the ride improvement was not as dramatic as I had hoped , it was an improvement. However the big bonus was a really drastic improvement in the handling. It has sharpened the turn-in, and taken completely tamed the rear end waywardness that is inherent using leaf springs and a powerful engine.

I think the balance between front and rear is really good, and the whole car feels so much better. I am now happy to let my wife drive fast in the wet and I will nod off in passengers seat (on longer journeys!)

Just to add I wasn't referring to the SSL kit but MMC's own version and spec of such. On a mixed road 240 mile trip on Sunday the ride was considerably improved by having a heavily laden suitcase on the rear carrier although only myself and small dog as passenger. As expected not a hint of bottoming out due to high spring rate and dampening but definately favourable articulation, maybe requiring a click more on the front AVO's as well, highlighting how the rear affects the front as Cain had previously suggested.

To cast the net further as I believe the ARP4 had similar 5 link rear (and have been around longer), I wonder what spring and damper rates were used on those.

I had assumed that, Richard.

I too have realised that playing around with the front suspension definitely affects the rear. In my case I have been trying to get the optimum setting for the front ride height (on the Suplex/SSL platforms) so the rebound springs are taken out of the initial loading on bump. This has had a big effect on the bump absorption at the front AND appears to have softened the rear as well (although I made no changes there)

To me the balance front/rear now feels pretty good running solo. I will be interested to see whether it changes when touring 2 up and laden.

Just had a chat with Dan White at SSL. Apparently they are already working on alternative coil spring/damper units. Thoughts are that MMC went for excessively stiff units to limit roll. SSL's own 5 link offering has top links angled inwards to limit roll, so allowing softer springs. For the factory system which has parallel links top and bottom, they are hoping to provide progressive springing using two end to end to give a more immediate effect on roll control. Conversion when available in six to eight weeks, will be adjustable for both spring pre-load and damping.

Richard, having discussed this with Dan a few times over the last 12 months, he knows the issues with mine (1st production 5link) problem is the spring length available on the MMC setup is difficult to get 2 coil springs in and not coil bind in compression, but fingers crossed he develops a solution

I have increased the size of the tyres to 195/65 R15 so this lifted the front end by 10mm. I then used 10X1mm shims (from the race kit courtesy of Peter Ballard) under and 10 over to lower the ride height to maintain the same front ride height of the car. On the rear, because we often tour with heavy luggage ( ) I have fitted slightly higher rated springs on the rear. I still need to play aroundd with the damping a little at the rear though. I still occasionally get bottoming out on bad bumps. It would be less of a problem if our roads were less of a problem

Yes I mentioned to him the possibility of concentric springs to achieve desired progression but don't know if that's practical. His follow up suggested not. Apparently a single progressive spring wouldn't give the necessary roll resistance so final solution will be something of a balancing act.

First complete assembled Spax coil spring/damper unit from SSL to address the over firm, over damped units on the factory 5 link rear. As promised adjustable spring pre-load and damping for these dual spring rate units.



Provisionally arranged to have a pair of these fitted next week at SSL allowing an immediate opportunity to evaluate

Well despite discussing with Dan over 14 months ago, us impecunious northerners are last in the queue

Many thanks for posting Richard, update patiently awaited, I'm so close to SSL you can call in for a cuppa

Long day travelling first to SSL and then return to Norfolk. Met the hospitable Dan White, a director of SSL, to have a pair of his prototype dual rate coilspring/damper units fitted. His able assistant Andy had them on in no time after jacking up the chassis just enough to remove weight on wheels and allow easy removal of mount bolts.

Meanwhile Dan explained just how they were going to work. The short higher rate spring at the bottom dilutes the rate of the longer softer spring giving an even lower overall spring rate initially as per the reciprocity formula of springs in series. After a calculated 25mm of suspension movement above static, the shorter spring becomes coil bound leaving the longer spring alone in play with consequent immediate increase in spring rate to limit roll.

As the new units were the same free length as OE, the swap over was very quick and easy.





Andy noticed the axle was not quite central to the chassis so that was tweaked as well via the panhard rod. Unfortunately this then left the wheels not centralised to the body, although only by a few mm, so a compromise was found. Dan and I then went for a 5 mile test drive on his favourite set of local roads.

I drove first and immediately noticed the expected softer ride. I could say it was like a magic carpet but that might be overcooking it It was a substantial improvement though with no more crashing over bumps as before. We tried a few speed bumps and it took those in its stride as well. What I wasn't expecting was an improvement to the cornering though. Sitting close to the back axle the improvement is felt literally through the seat of your pants. The sudden increase in spring rate limits roll even better than before increasing grip of tyre on outside of turn. This translates to even better tuck into corners although it was good before. Dan then had a very spirited drive and pronounced the settings as good as you could get in a single days testing. As mentioned before these units are adjustable for both spring pre-load (via locked base collar) and damping to compensate for driving style, touring etc.

Job done we retired to the pub for a late lunch followed by comfy home A very enjoyable and informative day.

I understand these units are now available for other 5 link Roadster owners.