Roadster Anti-Tramp Bar Issue

At the beginning of the Roadster Series II production (early 2008), the MMC made some modifications to the rear suspension. They attempted address an axle wind-up issue that was causing the prop-shaft to impact the car in it's most extreme expression. Their original solution was to fit a single Mulberry anti-tramp bar on the right hand side of the car.  These anti-tramp bars were already being used in paired sets on racing Roadsters. 

Traditionally, anti-tramp bars are always fitted on both sides of a car. But it was felt that a single bar would do the trick, cost less and the space on the right is partially obstructed by the battery and its fittings. The first cars with the Mulberry bars did well. Mulberry anti-tramp bars are designed for Morgans. They are additionally unique as the end at the axle are fitted with a compliant bush, press fit into the bar and through which a graded metal attachment bolt is placed. This compliancy allows the suspension to operate fully and freely, unlike many other anti-tramp solutions that inhibit the up and down movement of the suspension.

After the first few cars so fitted, the MMC decided to copy the Mulberry design in hope of saving costs. In doing so however, they used different fittings and changed the all-important bush to something less compliant. Anti-tramp bars on these Roadsters have a tendency to shear their bolts at the axle saddleplate and bend or break their fitting bolts at their front.  The improper but most common solution is to greatly reinforce the ends of the bars.

The MMC now makes the assembly with a more compliant bush and higher graded fittings than these first copies. These are a better idea for someone with this problem. The ideal fix would be to fit two quality anti-tramp bars, one per side. There are some doubts as to the long-term affect of a single anti-tramp bar on what is a performance sports car.
 

SUSPENSION NOTE (EARLY 2009 TRADS)

Sometime in 2008, the MMC realized that their new 4 leaf rear springs were losing their ride height, allowing the rear ends to prematurely sag to an unacceptable degree. There seems to have been an attempt to address this first with a higher arc specification but ultimately this did not provide the desired result.  At some point, the company turned to a new, higher quality spring supplier with an excellent reputation. (And the cost of Morgan leaf springs since doubled.)  Apparently, on fitting the first batch of these springs, it was immediately apparent that the arc specification given the supplier was now too high. Sop as to use these springs, the company fitted "lowering" plates between the leaf springs and the saddle plate. These are used by racers to give a car a racing profile (see racing Roadsters). In this case, they lower the ride to a more normal height.

However, in fitting these plates it is necessary to use longer u-bolts. Morgan rear u-bolt length is very important. If they are too long, they will bend and crack the thin horizontal flange at the ladder frame of the chassis.  If the thing flange is broken, a crack in the perpendicular "strength) section of the frame soon follows. A SPECIAL NOTE must be attended to by these owners. The newest leafs have the correct arc and ride height WITHOUT this plate. When leaf spring replacement becomes necessary, the plate should be discarded and NEW shorter u-bolts used rather than the originals with these "transition" cars.