I think the quality is crap. But driving out of the driveway. Needs some RPM, doesn’t like to lug. Engine meant for light vehicle 3,000 lbs with 3:73 gears and manual transmission.
It’s in a 5,000 lb truck with 4.10 gears and 33” mud tires. Still a manual. Maybe give it more timing? I dunno. Not a great tuner.