318 timing chain.....and why the engine should come out.

glhx said
I wonder about the @50 number

I’ve seen cams with a smaller @50 and a larger advertised duration and it makes no sense

I was taught that the @50 was to accurately compare cams from many companies.

But then I see a lot of mixed up stuff.
A 262 with 218/224

Then see the he268 with 218/218

And I think the k6900
With like an advertised 285
But he @50 is much lower than even the 262.

Which cam is bigger?

That tells you the steepness of the ramps. Less advertised duration with more duration at .050" means steeper ramps on the cam lobes which opens and closes the valves quicker. Modern performance cam designs use faster ramps, old-school cams (like the older Mopar Purple Shafts) use slow ramps. Others can chime in regarding how that affects performance I'm not super knowledgeable in that realm.