Anyone know the mm for coilovers springs? Looking to upgrade to swift springs

 

There's many different sizes of coilover springs. Best bet would be to contact the manufacturer and find out what they came with. Also something to consider in case you are looking at upping the spring rate, you will need to have the coilovers revalved for the higher rates if going more than 4-5kg over what the coilovers originally came with.