Re: " Just had a TBI---350 CI built with all the Edelbrock good stuff,
heads, intake,cam,headers and so on. The mechanic that installed the new
heads said that he thought roller rockers don't have that much benifit
if you are not running high RPM."
Your mechanic was absolutely correct.
"Roller Rockers" are a complete waste of money and are about as
helpful as a magnet on the fuel line.
There is NO power loss in the valve rockers in a stock,street driven
vehicle.If there was ,there would be major overheating that a little
trickle of oil would not be able to cool.Also there would be tons of
wear at the contact points.
I recently inspected my wifes 350 engine that has well over 200,000
miles over a period of 28 years of hard service and the wear at the
rockers was MINIMAL.They can go another 200,000 miles easily.If this was
a source of power loss from friction this would not be possible.
Perhaps at very high RPMs or when lift accuracy is necessary due to
the high performance nature of some race engine,it makes a measurable
difference,but you would be throwing your $ away.
There are three kinds of lies: lies,damned lies,and statistics.