Thanks guys for the additional info. I just dropped $100.00 on this head, I hate to start over looking for another head. This appears to have steel guides and seats in it already, is that the way the 260 came? I was planning on shaving it .030, port matching the intake and exhaust and polishing the combustion chambers. Will any of that help, or am I just putting lipstick on a pig?

The 260 E88 head had brass valve seats. I don't recall if mine had steel guides...they are now 'cause we changed them. The big problem with the E88-260 head is it has a big open combustion chamber with no quench. Welding the chambers allows you to build some quench area and shape a very good combustion chamber. I'm running 11.5-1 compression on 93 octane with 35 degrees timing and no pinging. 490 lift 290 duration cam helps bleed a little compression off. Bottom line is all the Z heads can be made into decent heads with a little work. The E88-260 just requires a little more.

Thanks to everyone that replied I appreciate all the information.

Craig

I have not heard of any E88 head with the steel seats standard from the factory. They all came with silicon/bronze seats, but we commonly call them brass seats due to the colour.

Off topic but since it was mentioned, I was wondering, what's wrong with silicon bronze valve seats? Not arguing, just want to learn something. Silicon bronze is tough material with a coefficient of expansion closer to aluminum than steel is. Have heard of performance engines using silicon bronze seats and guides.

Off topic but since it was mentioned, I was wondering, what's wrong with silicon bronze valve seats? Not arguing, just want to learn something. Silicon bronze is tough material with a coefficient of expansion closer to aluminum than steel is. Have heard of performance engines using silicon bronze seats and guides.

With unleaded fuel, valve seat failure was common with engines running often at wide open throttle or above 4000 rpm. Lead in the fuel provided exhaust valve seat lubrication and excellent heat transfer from the hot exhaust valve to the seat in the head and to the coolant system.

There are several methods used to fix the problem, including hardened valve seats, valve rotators, and sodium filled valves to transfer the heat. The hardened valve seats became a cost effective compromise and was adapted by most if not all of the manufacturers.