GMG,
Many thanks for that, much appreciated. I should clarify that the 4 seater Roadster rear suspension was easily overwhelmed with only front occupants, and bottomed out with rear passengers extremely easily. despite uprated adjustable shocks, which as you quite rightly pointed out once bottomed out tend lose their adjustability requiring me to increasing adjust them over time. I avoid using rear carriers, as years of motorcycling has taught me the adverse effect of luggage increasing weight over/beyond the rear wheel and moving the centre of gravity can be very detrimental to handling. and braking.
Do you have any thoughts as to getting around the restriction in turning circle caused by BRB's fitment?
I also meant to increase the ride height at the front, to reduce risk of hitting the Mazda bellhousing, I don't remember the ride height ever being an issue in my Kent or CVH engined Morgans, although speed ramps were far less numerous back then compared to now
I appreciate everyone's contribution, and one of the first areas to check is whether my rebound spring is already under compression.........
If your +4 is still on its original rear springs, it may have been built during the period where MMC used un-tempered liquorice for rear springs. Worth checking for sagging. The best source for replacements has changed since I did mine - I cannot remember who people are going to. As an aside, if your +4 Sport doesn't have a spare wheel then changing the rear springs is more difficult than on my 4/4 with a spare wheel.
On my 4/4 with 80 section tyres, I don't get any interference between tyres and brake reaction bars.
As regards ride height, our 1985 CVH engined car didn't really have a speed bump ground clrearance issue. The gearbox cross member on my current 4/4 (Mazda gearbox) seems to be hitting things on an almost regular basis.