The spring pockets need to be larger, as the spring is physically larger. I think TEA charged me $50 for the machine work, then you have to run the Comp locators (Comp 4712 ~$35.00) to locate the spring in the new larger pocket. Well worth being able to relax and not worry about any broken valvesprings, IMO. Shawn

 

Does anybody know about how much it usually costs to get the heads machined to fit 987 springs? What all has to be done? Thanks!