Cam and Valve Spring Question 16v

[brian_wagner at sbcglobal.net (Brian Wagner)]

All right after some horse trading I have acquired to set of stock 16v cams and will be sending a set to Delta to be reground. The question of the day is what is the maximum profile that I can use without changes the valve springs? I am only looking for a moderate gain of 8 to 10 hp (in reality probably a little less).
 
Shrick offers the following profiles
 
260, 268, 276, 284, 300
 
items that are bold ( I would assume you need different springs)
 
Your input is greatly appreciated.
 
Brian