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

Fitted my SSL rear Coilovers a few weeks back and at the time I only managed a very short bedding-in run, they definitely give a more supple rear that balances nicely with the SSL front kit which I already have

As we're all in lockdown, I thought some 'spanner porn' would be appreciated

Here's before with the MMC stock set-up



And after with SSL, giving adjustable pre-load & ride height fine tuning, and adjustable damping on the shocker

Also the dual spring set up gives a rising rate system. As the main spring reaches maximum compression the lower spring, which has a higher rate, comes into play.

Although I initially thought the same as you it's actually the other way around Peter. Dan at SSL explained as follows:

Both springs compress initially but the shorter spring becomes coil bound first (at around 25mm total compression from static) despite being the higher rate, thus leaving the longer main only in play. Seems counter-intuitive, but when both springs in play, being in series, the combined rate is lower still. Once you've got your head round this it all makes sense

Thought I would add my thoughts to this thread, having owned my Morgan with full SSL setup for 6 weeks now.

One of the reasons I bought this specific Morgan was because of the suspension upgrade. It’s a decent wedge of money, so my expectations were high.

The first drive out on smooth roads showed the car had impressive road handling and flew round roundabouts. However on more uneven roads I found the ride to be less controlled and creaks and rattles were coming from all over the car. Off speed humps at low speed it sounded like bits would fall off. First thing I did was to check damper settings, where 14 clicks is maximum. The front was at 9 and the rear at 13 ! Softened these off to 4 on each and ride quality improved but still far from perfect.

I reached out to @PJB and overall several weeks Peter helped me tweak the settings. I had to back off 5-10mm on the seat springs at the front to get to a point where the spacer kissed the hub. I also found general cleaning of suspension, lubricating the bonnet strips and applying oil between runners and body helped eliminate a lot of the noises.

I have to say , without doubt, the service PJB gave to me as a 2nd owner of the suspension was incredible. Far surpassed my expectations. So thank you Peter

Now the final update is tyre related, so I will put my findings in my separate thread here http://www.talkmorgan.com/ubbthread...h-tyres-for-2011-plus-4-sport#Post642177 . Upshot is though, the ride of the car was being substantially impacted by old rubber. 4 new tyres fitted last night and the ride has improved 100%. Only now can I experience the full benefits of the SSL setup. It’s a completely different ride to when I first got the car, so happy bunny here.
When we get to a point where we can swap rides, happy to let others take the car for a drive to compare.

Dave

Sounds like you've made some great improvements Dave!

Have a look here at the first graphic with the red line.
https://sites.google.com/site/morganatica/suspension/springs-progressive-rising-rate

I am not talking specifically about the Suplex type, but first of all about the normal front axle.
It is definitely counterintuitive
In the arrangement of the Morgan front suspension it is not a series arrangement. It is a parallel arrangement. With that the contra-intuition already starts. Both springs add their forces in the arrangement. It is not a series connection. When the lower spring presses together with the upper spring on the wheel hub, force is very high and the suspension is hard. Unfortunately, this is already the case when you only need little spring power and the car could be driven more comfortably (this is what the properties of the Suplex principle build on to change this disadvantage).
If you drive over a bump with the lower spring already preloaded and the upper spring is compressed but suddenly the lower spring loses contact, then only the upper spring is in play. As a result the car suddenly sags.
In principle the lower spring is responsible for two things. Firstly, it is responsible for preventing the car from tilting in curves (on the unloaded side it prevents the car from climbing up very high) and secondly, it is responsible for the controlled escape from a bump.

It always amazes me when I replace tyres on my Mog how much the ride improves.

Yes, one of the lowest cost suspension upgrades you can do along with not running the tyre pressures too high

Having a car with MMC developed 5 link rear, I would be really interested in a comparison of the two arrangements. PJB, who I agree does go the extra mile, will always say that the Suppex setup is better, however a less biased opinion would be interesting. 5 link rears are definitely the way to go though.

I know which Cain (Wolf Performance) prefers for traction

To be fair the SSL version is technically superior but the MMC version has the link mountings welded to the back axle. It does benefit from the addition of SSL dual rate coilovers though.

I've also heard from more than one source the SSL 5 link kit has too softer springs. I believe Peter (Gambalunga) asked for higher rate ones for his car.