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Question:

Big block, solid lifter, valve clearances?

Have an iron block, aluminum heads, solid roller lifters, Jessel rocker shafts, what should my valve clearances be cold, and hot??

Answer:

Your cam dictates the valve lash. What cam is in this engine? Contact the cam company. Most have on-line tec support or a 1-800 customer service department.
Only way to be sure is to put clay on top of a piston and turn the engine over by hand and then measure the clearance on the indentation in the clay.
On solid lifters tappy is happy I don't have a manual here, but if you need to get it going now that phrase will help you.
Because you apparently have a built engine here rather than a factory assembly which simply has solid lifters, and the data you have is either inconclusive or conflicting then I will recommend the following procedure: Assemble them cold and adjust to Intake .010 and exhaust .020. After firing up the engine, adjust the carb, if it is so equipped, to a smooth rich idle and run it in for a couple of hours mixing idling with moderate load and a few full throttle pulls through 2nd gear to seat the rings. Bring it back into the shop good and hot and set the valve clearances at .008 intake and .016 exhaust hot. After adjusting the valves readjust the idle to 700 RPM and set the timing. initially set the timing at about 2 degrees BTDC until you hav run in the engine, If you are without clear specifications for timing use a vacuum gauge and play with it between 2 and 10 degrees BTDC with the vacuum advance disconnected and plugged, you are looking for the highest vacuum at idle as a starting point. Run it hard including lugging it in high gear at around 2500 to 3500 rpm at or near full throttle, if you are getting spark knock back it down 2 degrees at a time until it does not knock when lugged. If you get no spark knock when lugging it you might try advancing the timing 2 degrees above the vacuum indicated optimal setting but do not go beyond that point. After setting the valves and timing readjust the carburetor to the best lean idle and set to 650 to 700 rpm depending on where it feels comfortable. In the old days a lot of this was done totally by ear - hence the term engineers. Today I think most holders of that revered title do not have a clue where the term came from.
Well, generally it's going to be .030 intake and exhaust (hot). Adjust to those clearances cold then recheck at operating temp. But it would really help to know year, make, cu. in., which aftermarket heads, to be absolutely sure. On some engines it is .024 intake / .030 exhaust and so on, depends on the lifters and valve train geometry.. What brand of lifters and cam profile? Usually they will specify valve lash and adjusting procedures. Edit: Wow, kinda' tight valve lash, krazybob, ( might be a lttle tough on the old cam lobes), and then there is your timing numbers / advice with absolutely no details to base it on ( H.E.I.?..which brand? / mechanical advance curve?, and vacuum advance numbers?, cam timing, brand of lifters, cam specs, rocker arm ratio)...Look, S-51D, the best idea is to Do- It- Right using the correct adjustment specs. The data is out there, once the configuration is identified.

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