>AMC never used hardened seats in any engines. Well, I don't know about the 2.5L four, but I would think not >since the 4.0L never got them. My understanding is the slightly tougher castings allowed induction hardening of >the entire lower surface of the head, valve seats, combustion chamber and all. That would have occurred on >roughly 78 and later engines though. I don't know if hardened seats are a requirement for E85/alky, but most >likely is due to no lubricating qualities. Doubt it's any worse than unleaded gasoline though. Where in the world did you get that?? Don't confuse E85 with LP. "Induction Hardening" is a localized area type of treatment typically given to the Exhaust seats as a cheaper way of treating the seats compared to installing replaceable seats. I have done a LOT of headwork in 40 years and never seen a head where the entire lower part of the head is treated. That would make no sense operationally OR financially as the only place you really need it is the Exhaust seat. That would make the ENTIRE lower half of the head hard!! Maybe there are engines that have it,,, I've never seen it,,, Now I HAVE seen engines that will wear the Intake seat too (old 390 series Fords are one example) but they are pretty rare and usually in HD applications. MOST manufactures started treating Exh seats in the mid 70's and most all engines had them by 1980. Aluminum heads are exempt since all of them have replaceable seats and most are hard enough to work OK,, even on LP. There are NO different requirements for valves/seats when using E85 than Regular Unleaded fuel that I am aware of or have seen. Here's some real world evidence,,, http://www.youtube.com/watch?v=I-MNQFlRilE&feature=related And I STILL think Butanol is a better fuel,,,, But HEY,,, that's just me! Bruce Hevner -------------- next part -------------- An HTML attachment was scrubbed... URL: http://splatter.wps.com/pipermail/amc-list/attachments/20080601/c52a4789/attachment.htm _______________________________________________ Amc-list mailing list Amc-list@xxxxxxxxxxxx http://splatter.wps.com/cgi-bin/mailman/listinfo/amc-list