Scooterotica

I have a modified rb20. 32 tm mikuni, 62mm crank, case weld and transfers opened up all the way on the cylinder. I currently have a jl mk4. It's the full race. I'm not a huge fan. Although the power kicks in like a turbo it has very little torque down low. I am looking for an exhaust that will give me torque down low but will allow the motor to rev high. There are many choices and I am a bit overwhelmed.  Any thoughts, experience, recommendation is helpful. 

Chiselspeed CST 4, CST 6, or cst 8

Rayspeed nk 

Franspeed sport tourer

Pipedesign Voyager 

Or is the answer a variable ignition ?

A variable ingnition my help with the low down power problem allowing it to pick up before the pipe kicks in.

I don't think you can make a choice based upon the only information stated. Do you know your port timings?

(I have just responded to a request on this Forum about base packers & with some of these cylinder kits as standard, they need to have a decrease in transfer port timing. That is one of the main advantages in 'stroking' a two stroke, gaining blow down, should it be required)

That said, the advice about ignition is good, though that alone will not solve the characteristics of your engine. The first advance/retard ignition I ever used convinced me of the benefits in tractability gained, & that was in the 80's. You probably need a programmable set up, but don't be surprised if you find the necessary retard to be in the order of 10 degrees.....

The exhaust timing is between 185 and 188. Sorry I cant be more exact than that.