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

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.