[myblueheaven]

All over catalogs and ebay sellors of pontiac parts i see the stock pushrod length of 8.693 and 5/16 wide shaft. Yet all over this site i see varying lengths from 9.7... what ever to 8.7... what ever, and evrything in-between --. Not the 8.693. - Even sig erson has theirs at 8.693. I can't find any for sale that are different than what i see for sale.Yet many many users on this site declare all kinds of different lengths, giving all kinds of different reasons to have them. If I go to a parts wherehouse and simply ask for a set of stock pushrods for my 1969 350 CID, are they going to ask me what length or simply give me one size and be done with it. I built 3 other pontiacs and assumed the rod lengths were the same for all pontiacs and all the engines worked great, though the pushrods I purchesed were from different sources like sig erson, comp cams and a even Pep Boys! They were all the same size? Did I just get lucky each time I built my engines not knowing there may be a different spec push rod to use for certain applications or is there really only one standard and then custom lengths for odd non stock spec engines that are the creations of the builder? Thanks.

[b-man]

The standard stock pushrod length for 99% of all Pontiac engines built after 1966 is 9.145". The 8.715" (8.693" is close, replacements seem to vary a little for some reason) pushrods were used on the '61 -'66 engines before the change to the later head design where the valve angle changed and the valves were moved to the center of the chamber.

1967 was a transition year where both lengths were used, the longer ones were used on GTO and GP big-valve heads.

The RAII, RAIV, RAV and early SD engines used different lengths over 9".

Your 1969 350 uses the 9.145" pushrods. You probably just got lucky in the past, the wrong pushrods for whatever year you're working on just won't work right.