I have a set of used series III S/C heads that I had oversized si valves put in the biggest you can get, ported polished runners exhaust intake and bowls, comp cam springs for an xpz cam set up on stock rockers and the under cut retainers for extra valve guide seal clearance. Well 5k miles later one of the guides got lots of play in them I bought a set of 12 bronze guides from si same ppl i got the valves from and the head actually has to be machined to accept the guides there 1/2 inch od and they will need to be cut down to the right length the come at 2.750 inches long and the id will have to be honed possibly after install I will have to double check the id and vavle stem and see what clearace if at all I have to start with and I was just wondering if anyone else has had this done because there is not much room for error in the valve seats or the valves crashing with the oversized valves if the guides are off just a bit. Also is there a differnet or better guide to use other then bronze?
