Argon Z

has anyone ever had any trouble with brass valve guides

LS1derfull

Do you mean bronze guides? They are good with hi rpm and hi spring pressures because of their lubricity, but powdered metal stock type should last longer in street use with mild cams and spring presssure.Bronze guides allow for tighter stem to guide running clearance which helps valve job last longer.

PurEvl

iTrader: (2)

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by LS1derfull:
<strong> Do you mean bronze guides? They are good with hi rpm and hi spring pressures because of their lubricity, but powdered metal stock type should last longer in street use with mild cams and spring presssure.Bronze guides allow for tighter stem to guide running clearance which helps valve job last longer. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I see the computer is working again eh <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />

wolfman jack

dont you want to run more stem to guide clearence to make up for the higher expansion rate of the bronze over the steel?

LS1derfull

Bronze is very soft and will not tolerate loose stem clearance.Its lubricity allows it to be run tight for better valve seal and valve job life.Steel guides(iron, or powdered metal) expand more requiring loose clearance to prevent grabbing.
Actually the way it works is bronze conducts or absorbs and dissipates more heat from valve, allowing it(valve) to run cooler and expand less.

Argon Z

thanks