Generally speaking 30 degree seats will flow slightly more at low lift (say .250 or so and less) than 45 will due to less valve shrouding by the valve itself. They also tend to wear the seat less due to less sliding action as the valve opens and closes. Unless it's a stock valve job I change all my seats to 45'. Most of the time the valves will be replaced so that 1 piece valves will be used. To my knowledge MOST HP valves are supplied in 45'. But HEY,,, that's just ME Bruce Hevner -------------- next part -------------- An HTML attachment was scrubbed... URL: http://splatter.wps.com/pipermail/amc-list/attachments/20081029/4db4b9a3/attachment.htm _______________________________________________ Amc-list mailing list Amc-list@xxxxxxxxxxxx http://splatter.wps.com/cgi-bin/mailman/listinfo/amc-list