59AB valve train questions

J

JunkyJud

Member
I am rebuilding a 59AB for a Model A pickup with a stock rear with 3.54 gear that will run 65 mph tops (mostly 45 - 50). This will be a driver and not one that will be beat on. I'm to the point of putting in the valve train and need some rational guidance on the valve and spring choice. I'm not trying to prove anything with this build, including the money I spend. Here is what I have:


- 59ab block bored .040 over
- 8CM Mercury crank
- Stock style .040 Sterling pistons NORS
- Re-ground stock cam to 8CM specs
- Stock, solid NOS lifters
- Re-ground original valve seats with one that was replaced


My valve length requirements (with no lash accounted for) range from about 4.848" - 4.873" (the one with the new seat). This seems to put me in the Chevy valve length range. Here are my questions:


- Should I run stainless Chevy valves on both intake and exhaust?
- With the 8CM grind, should I run LZ springs or are the stock style okay?
- With the Chevy keeper position being lower, and this being a mildly driven engine, will I have to shim the springs or is the extra installed length not too much of a problem? I want to avoid shimming.

- Are there better options than the Chevy valves considering the length that I need?
- For the amount of valve tip that needs to be ground off from a 4.9110" Chevy valve, will I lose the hardened end?


Thanks for any input.
 
All of the parts you list or any combination of should work fine in your engine.
I would recommend you NOT use the stock lifters that have the elongated slots in the side. They are cast iron and prone to breakage.
Use the ones that have 2 small 5/32 holes in the side. Be sure they are new or have been refaced on both ends. DO NOT put used lifters on a new or reground cam.
You should at least check all of the valve springs for the same pressure at the installed height.
If any of the valves come up short, the ends can either be TIG welded with 347 stainless or built up with Eutectic 16FC bronze rod.
 
Yes, the lifters are original style NOS. They are hollow and have the small holes on the sides. Thanks for the reply.
 
I am really not the motor expert, pete^^ knows his stuff, but for a cruiser I would think there is no reason for stronger springs, like LZ, thats mainly for high RPM race motors
 
A good set of stock replacement spring should be fine . . . you're not putting in a big cam and the engine won't be turning high RPMs, so using a lighter spring will help your cam last longer (less wear on it).

You'll need to find a machine shop that knows how to setup the valve lash and has the right equipment and knowledge to do so.
 
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