I hazard a guess at a m120~ spring, or an m110 if the airseal is really really good. If the components around it have a really shitty airseal, could be as high as m130.
Safe bet is m100 which should be 360ish
gambling that you could go over 400 still, you can try a m110.
I futz with V2s, V3s and V6s. I could be wrong... but probably, most likely not, as far as I know.