340 Chugging instead of Reving

512Stroker said
Rat I agree about the cam timing should have been degreed in.
If the cam timing were way off wouldn't it run poorly through out the entire rpm range? Food for thought.
The plugs a pig rich but that again would not cause a sudden change at 3000 rpm.
Im inclined to point fingers at the ignition system like other members have suggested.

I once had a ohc engine thst I screwed up the cam alignment on, advanced something like 14deg (about 1 timing tooth) and it would rev to about 2800 and then pop, fart, spit and buck.

Completely different engine, but similar behavior, so I wouldn't ignore the cam timing... Just my take.