Midget suspension only really changed in detail during the life of the car as it evolved from the original 950cc Frogeye to the final 1500s. It was always leafsprings at the rear and col springs at the front with lever arm dampers providing extra location.
You can go miles with Midget suspension – there are numerous bolt on bits from firms like Frontline – but if you’ve got relatively low power like I have it seems to be overkill. I don’t have much problems with traction (I can’t launch any more brutally because I worry about breaking the diff and/or driveshafts) and the car behaves very predictably at high speed on circuits such as Goodwood.
At lower speeds it even copes well with off road in the rallies
Anyway, my cars got uprated dampers – standard lever arms revalved. They have also been painted red which makes them much faster.
My car also has lowered springs. As standard 1500s sit higher than the chrome bumper cars and the “rubber” bumpers are remarkably heavy. If you remove them, as the previous owner did on my car, the whole thing boings up even higher. So you are going to need lowering springs for both looks and handling. I’ve only ever dirven one 1500 on standard suspension, but on a heavily crowned and bumpy road, the car was terrible. Quite frightening as it veered around and bounced and boinged from one bump to the next.
One of the best modifications to any 1500 is to remove the bumpers. This causes the whole car to boing up in the air and become even more unstable so you’ll definately need some new springs.
Obviously with the lower springs the centre of gravity will be lower so you’re already going in the right direction. You don’t want to stifen it too much. My rear springs are lower but no stiffer. This is for traction off the line which seems pretty good (here on the GP circuit Silverstone).
The front is lower too but these are stiffer. This should help getting the car to turn in.