First Generation Firebird-L Mailing List .........................................................................
I've been reading this thread and it raises a question on compression ratio. I'm going to have my 400 rebuilt. As far as I know, it's currently stock so it would still have the 10.75 CR. I have not noticed it having a pinging problem althought admittedly I've driven it very little. My original FB400 seemed to get along fine on the premium unleaded of the day with a conservative centrigical advance. Yet several in this thread have indicated problems with todays gas and the high compression ratios of these 400's. My understanding of current Octane ratings is that current 91 octane is around 93 under the old system in use at the time these engines were built and should be fine for these engines. My 64 T-bird, which had a 10.5 CR didn't seem to have any problems on today's premium. So what's the common wisdeom here??? I'd hate to have them rebuild it with a lowered CR if it's not really necessary to do so. ------------------------------------------------------------------------ Submissions to Firebird-L: <[email protected]> Unsubscribe from Firebird-L: <[email protected]> Help: <http://FirstGenFirebird.org/firebird/Firebird-L.html> Classifieds: <http://FirstGenFirebird.org/ubb/> Owner Pictures: <http://FirstGenFirebird.org/show/>
