1972 and newer chevy small block heads had hardened seats for running unleaded
gas, unless the 327 you have is a hi compression engine you shouldnt have any
problem running unleaded gas, performance will slowly fall away as the valve
seat wear do to lack of lead lubrication .. you can buy in some states lead gas
additive that will enable you to run unleaded gas without eventual valve
damage,, but additives can be expensive over time. If your engine is in pretty
good shape and all you want to do is run unleaded gas you may consider either
buying a set of heads that are 72 or newer or have yours reworked with new
hardened seats,, check with your local machine shop for pricing,, I just paid
$180 to have a set of heads reworked with out the added expense of the machine
work, labor and cost of seats, I imagine it would be cheaper to buy a reworked
set of 72 and newer heads,,, if you have a higher compression 327 engine with
smaller chamber heads you may probably want to buy a later set of heads with a
larger combustion chamber and install them on your block,,,the higher
compression heads you dont want can be easly sold to a corvette enthuisast or
some one who is builing a race engine.. if you remove your valve covers you
can obtain the casting numbers, as well as determine the year they were made
from the casting ID, on the front of the head there are distinct casting markes
that help Id them too, but the best way is to pull the valve cover,,, becareful
when buying heads,there are some heads that are of lighter casting that are
undesireable,,They are prone to cracks because of the lihter casting and poor
circulation.. you can forward your casting numbers to me and I can look them up
and give you the information on your heads,, someone may have allready
installed later heads on your engine and you may not need to do anything.. good
luckRichard57 cameo
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