FRPP A-50 valvesprings?
 

Has anyone here ever used these? From what I've read,and what is says in the link,these will work with factory heads. I've read on the corral,and IIRC SVTP,that these will work with the factory retainers which have different installed heights on intake and exhaust. Anybody know for certain?:shrug:

http://www.fordracingparts.com/parts...artKeyField=44