Some will argue this to no end.
I will say from my personal experience that I have run 1.9 modified rockers on stock springs with shift point above 6000 for quite a while and had 0 issues.
Although some have done this and said they broke springs. Personally I think it was because of other issues.
The point of the higher load springs is to reduce or rather eliminate the possibility of valve float. It's not to get a ''tougher'' spring so they don't break on you.
I'm not sure what Scotty was getting at in his question above but a roller rocker would be ideal if you have the cash.They cause less friction and are a more accurate lift of 1.9 compared to the lift of the modified 1.9's because of how the modified 1.9's are made.
