Sell it and buy a 82 model CR250 , heaps of torque! 83's ain't bad either.
83 CR250's are a great bike!
The 84 RM250 cylinder is more torquey with more bottom end than the '82.
Machining 20 thou from the bottom of your '82 cylinder will help in 2 ways by lowering the exhaust port and raising the compression..