@redgumby --- ok I looked at your other post in Welcome Wagon where you shared some good info. What is your initial timing? What RPM is it at total? Sounds like your concern is that it's sluggish at the start but levels out, correct?
And you retarded the cam duration @.050 int 271 exh 275 lsa 108. 12.5 to 1 compression 76cc heads. Cam is installed 4* retarded. I don't know what initial timing is as it runs of the trans brake at 4500 plus rpm. Total timing was 38* set above 3500 rpm. Yes, it seems slow coming off the brake but then winds up very nicely.