i am upgrating to cosworth cams for my 9 ,supertech valve springs and retainers, also getting a triple vale job done and light porting ,ie blend bowl into seat area ect ,my head man asked what the spring height should be ? as he can shim them and make them all the same , i checked around and cant find a answer, can anybody help , thanks

 

http://www.junauto.co.jp/products/cy...lve-spring/?en


I would think that supertech should have an answer for you. After that I would check with cosworth to see if the tolerance from supertech is adequate for cosworth cam.... Above link was for your reference so that you can get those info from manufacturer of your parts.....

 

well after a lot of research i got a hold of a surertech engineer , supertech products are made in argintina, but i talked to a us rep, spring height for a evo9 is 39.6 mm thats with the valve closed ,Supertech offers 3 spring rates for a evo , first, part #m10007s , 78 lbs at 39.6 mm valve closed ,200lbs @ ,11.5 mm, max lift 15.5 mm, #2 part # m10007d 96lbs@ 39.6. 246lbs@11.5 lift , max lift 15.5mm #3the tech said these springs are for drag , short endurance moters as they would actually slow your moter down ,fighting spring tension, part#m10009d 120lbs@39.6mm, max lift not spec ,but the tech said, lift is less than 15.5mm as the inner spring would cause coil bind ,this is all part of blueprinting a moter if your moter builder dosent ask these question about spring height , i wouldnt use them ,as this measurment is part of a pro blueprinted engine build, thanks daninPA as you got me on the right track ,i knew there was a answer to my question thanks all