The earlier Comp rockers(prior to them being bushed) came with the recommendation of 350lbs max open spring force.
I’d also use high zinc oil.
I did have some issues with the unbushed rockers and roller cams using springs that had about 525lbs open force.
Actually, now that I think of it....... one of the problems was with a SFT cam application and just under 400lbs open.
BUT, they were running gas mileage type Mobil 1.