When I hit the key it spits and sputters then takes off like you got your foot mashed on the throttle. I shut the key off when it hits 4,000 RPM's, I figure thats plenty high enough on a brand new engine.
When I still had my 87 YJ I picked up a 4bt to put in it and never did. Sold the YJ to buy a 79 Dodge 150 with a BB383 that was bored and stroked to a 402. Should have never sold the YJ. I later sold the 4bt since I didnt have anything to put it in. Then sold the 79 and found this XJ.