First Generation Firebird-L Mailing List ......................................................................... Just to add, depending on your pistons and what heads you go with; consider the fact that the cam may need to be changed.
As you may know, many lower compression to prevent pinging due to the lack of fuel octane. Back when I ran the original 62 heads [10.75:1] and 91 octane fuel, I had to retard the timing to prevent pinging. And, the more the timing is retarded the hotter the engine runs etc. Fortunately there are a few later cam grinds that are designed to work with the older high comp heads by lowering the effective/dynamic compression. In terms of the 6x head, many are happy with the performance and select it because of it's availability. The heads Joe listed would be nice to have, but they're not readily available - they only came on a relatively small percentage of engines, hence the price. The 6x runners [with some porting] are not significantly different than the HO heads at least not enough to notice on a street car. So, unless you're a purist or going for tenths on a track, the 6x is a popular alternative. Also see: http://ronspontiacpage.com/reference-pages/stockheadspecs.htm PeteJD [69 400/400] ------------------------------------------------------------------------ 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/>
