Well having built race cars & fast street cars as well the best I have seen is a simple ladder leaf with a floater combo , it is hard to spin the tires even in the rain .We have had cars win 100" shootouts , they produce consistancy even with varying track conditions .
Playing with the stock suspension will net some gains as well, the pinion snubber simply works but it is horrible on the street , adding froward sections of leaf spring & clamping them tight with a square to U bolt stiffens the front leaf section & tranfers a lot more power as well .
4 link systems do work but tuning them in can be a nightmare , there are over 250 possible settings & finding the right one can be a long process & then if you run on a different track or different traction on the same day you are lost again .
I have set up 2 Caltracs with minimal results , they are a variation of the old Leaf link designed by Mopar back int he 60s