350 Rebuild Kit
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The small block Chevrolet engine has gone through several changes over the years since its induction to the Chevy engine family back in the early 60's. The first notable change was in 1969 when all small blocks went to the larger 2.100 rod journal and the 2.449 main journal size.
In 1979/1980 they moved the dipstick location from the left hand (drivers side) to the right hand location that was used all the way up to 2002.
The next change to the engine came in 1985 when chevrolet went from a 2 piece rear main seal to a 1 piece rear main seal, decreasing the overall rear main seal leaks associated with the engine and making it a less labor intensive repair if it did leak.
In 1987 Chevrolet brought about a new valve cover bolt pattern which moved the location of the bolts from the outer rails of the cover to the actual center line of the cover, giving an more even distribution of force on the actual gasket,
once again eliminating the majority of the valve cover leaks associated with the side rail bolt design. In 1987 the other change that was made was to the bolt pattern on the intake manifold. The center 4 intake manifold bolts were angled upwards allowing easier accessibility to the bolt heads. This change made it so that the intake manifold from 1986 and earlier would not work with the 1987 and later heads. The combustion chamber of the cylinder head design after 1987 went back to the 64cc size from that was used in the late 60's as opposed to the 76 cc chamber used through most of the 70's and early 80's.
In 1996 the final change to the engine family was made with the induction of the final Vortec version of the engine. This change implemented a new plastic timing cover and once again a new intake manifold bolt pattern and a raised Vortec intake runner.
Please note that during the late 60's and early 70's that there were several different size combustion chambers used in the cylinder heads and you will need to double check your casting number to confirm what size chamber you have for compression ratio purposes. Most all the heads used after 1976 were the same chamber size up to the mid 80's when Chevrolet had some model specific heads produced for cars like the Corvette and the Camaro.
All Performance Kits below are for 1969-1984 model year engines.
Call to have a performance kit built for your 1985 and later engines