Evan---Roller rockers reduce friction on the rocker shaft, and some also
have rollers at the valve stems. The ones at the stems give these stems
a better chance to decend into the valve guide without a side load, and
this should make the guides last longer. I don't believe this to be a
good place to first put your money, as you can buy a lot of guides and
rocker shafts for the price of the roller rockers. There's very little
performance gain with this modification.
Now if you get the set of RR's that increase the ratio, then you will be
holding the valves open longer, permitting a duration that allow more
air and fuel to enter. This will give you more performance, but like
most performance mods, takes more fuel to get it. C'est la vie. This
method of improvement usually is down the list for most enthusiasts,
going after such things as raising the compression, and the lightening
of the flywheel. RR's are very useful when using a high performance cam
that requires stronger valve springs, where wear would be accelerated
on the stock valve drive train.
Others may say differently. There are those on the list who have the
RR's and can tell you the benefits. Tim?
Dick T.
'73
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