Mick, check the open pressures(all of them) on those roller springs. I would break in the cam in with the Eddy springs and then, if the open pressues is not over 400 lbs, swap the roller springs into the motor. I run 165 to 190 lbs. on the seats and shoot for 375 to 425 lbs open, but you should absolutely break the new cam in with less pressures