I also have the Mulfab 4 seater leaf springs in my 4/4. Weightwise it should also work with a Plus 4 in the rear. I have been very happy with them for exactly two years. The car does not drive hard but nice and very controlled. When accelerating in the 4/4 I have a more direct conversion of power into movement than before. The old original springs had two problems. 1) they were too soft and the car constantly touched the frame. You can compensate this with too hard shock absorber settings, but that is not good and not the point of a good suspension. 2) The original too soft springs bend over before the power on the wheels changed into movement.
I did not notice any difference in the height of the car. Or if it should be, now the height is just right. In 2018 they cost £258 including shipping to Germany.
