Steve:
Yes you should always control end play even with a solid flat tappet camshaft.
It could be said that its more important than on a roller. In My Opinion.
Assuming its on a Chevy right?? What brand of engine in the old days had more OEM camshaft failure than any other?
If you said Chevrolet than your Right!!!
The engines that do not use a thrust plate to control camshaft movement relied on the helical cut gears on the distributor
drive to pull the camshaft to the rear of the engine during acceleration.
This keeps the camshaft lobes in one spot and the wear pattern on the bottom of the lifter happy.
The camshaft lobes are not flat. They are ground at a slight tapper. The lifters are also not flat. They are spinning when being ground and have a slight crown in the center. The high edge of the cam lobe rides on the outer edge of the lifter causing the lifter to spin in the bore.
The tension on a good tight timing chain set keeps the camshaft from moving forward when you let off the gas pedal and life is good under the timing cover.
Now your 1974 Impala has 67,000 miles on it and the nylon teeth on the top gear are all in the oil pan and that timing chain
is about ready to jump a tooth. Your cruising along with the 8-track playing Chech and Chong and de-accelerate for a stop sign coming up. That camshaft is chucking as far forward as that loose chain will let it, sometimes the only thing stopping the cam from falling out is the 3 cam bolts grinding into the timing cover. Now the lobes of the camshaft are moving forward and backward 3/8" of an inch. The camshaft can not make the lifters spin anymore. Now your cam and lifters are done.
Long story short.......
Control the end play on the camshaft and you will not only see better cam life but your ignition timing will be a lot steadier.
Matt
P.S. Camshaft end play should be limited to about .010 to ..020 in a perfect world.
