I ran a plus21-4C for a long time and absolutely loved it. Love the long runtimes with 10 minute pits easy. Also love the powerband. Nice bottom and mid. Usually ran with a 2096 or 9853 pipe.
Now I will be buying another engine.Looking at the btt. Is the btt much improved over the 21-4C? Does it have a different feel? I am looking for great runtime, with a strong bottom and mid.
Go with the btt or stick with the 21-4C?
The C has a little more bottom end over the Btt. But the Btt is smoother, with a slight top end advantage. I feel the Btt with the right clutch and pipe set is plenty capable. The btt will still blow the tires loose with a 3 shoe 1.1 spring set up