Hydraulic Lifters, JOHNSON HYD. LIFTER 231-252 V6, TA_V1405J

Do not under estimate the importance of your lifters. TA 1405 series lifters use the original GM type valving and have a hardened face to prevent wear. We recommend you use our TA Hydraulic lifters for any hydraulic cam combination. TA Hydraulic lifters can rev to 6500 RPM and are designed to maintain precise valve timing under all operating conditions. Part No TA 1405 incorporates a constant orifice metering ball check valve that provides precise oil flow to Buick shaft mounted rockers via the hollow pushrods.

-- Prior to 1970 Buick oiled their rockers via integral passages on the cylinder block and cylinder heads. Oil was delivered through these passages direct into the rocker shafts. The oil was then distributed to each rocker by a feed hole in the shaft at each rocker position.
-- 1970 and later Buicks oiled the valve train in the more conventional manner: up through the pushrods.
-- In order to use TA 1405, TA 1410 or TA 1415 lifters in pre 1970 engines a few simple changes are necessary. Other than changing the lifter to the later model you will also need to use a hollow pushrod (`70 and later) and `70 and later rocker assemblies. If you would like to retain the earlier style rocker assembly; TA offers Hybrid adjustable pushrods that incorporate the smaller radius tip at the lifter and the larger radius tip at the rocker. You will also need to block the oil feed passage that delivered oil to the rocker shafts. Block this passage in the head itself or in the cylinder block.