When I was club racing, we put 38mm carbs on our icc’s and were slower. To much wheel spin out of the corners. Moto engines are worse, big time bottom end, high comp will add bottom end so will advancing the timing. Im assuming an autocross track is very low grip, prob already a challenge to get it to hook up off the corner. Also, if you pump up a moto engine, they become very finicky, hard to tune and easy to damage. Ive raced both built moto and stock moto in the same weekend and in a few sessions was faster on the stocker. The built moto had a very small tuning window, if you didn’t hit it rite, it was a turd.
You can work on your driving in places other than an autocross track. Go to the local sprint track (if you have one) and pound out laps. Learn to drive in a little deeper, be smoother on the wheel, spend time changing the chassis, learning how to take out and add grip etc etc.