Frankly I don't buy this.
You don’t have to.
I have seen it happen first hand.
The stamped timing cover won’t hold the forward thrust if it’s on the high side, nor will the nylon button(which is why I won’t use them in a roller cam application).
The SBC community has reinforced covers, along with waterpump housings that have stop bolts to support the timing cover from being pushed forward.
However, that stuff only works to prevent cam walk from the cam moving foward.
There can just as easily be the same amount of force rearward as what there is when I timing cover gets bent outward.
The plain gear being pushed hard against the block wears a groove into the block........ like what happened recently to a customer of mine who has a roller cammed 505.
When he pulled it down for freshening, the area of the block where the cam gear rides is badly worn.
No thrust bearing on the back of the timing set.
http://www.iskycams.com/how-to-prevent-roller-cam-walk.htmlhttps://www.hotrod.com/articles/cam-thrust-explained-killing-engine/
