The stock ignition can make about the same power, but the curve is a little nicer with an ignition with more retard build in. Over 50hp is do-able with a stk stroke 250r, with the stock ignition, and inframe pipe/pump gas. And It can be done with a very nice power curve. The 4mm stroker crank is worth around 5hp on this size motor, if done corrctly. Even more fun is the fact that a well setup/tuned alky/4mm/drag piped/stk cyl 250r can outrun most drag 370 prox setups.