There is no quick and easy solution and you want to be careful about making something with no rear suspension go fast. I have a kite string on the govenor lever that comes off the engine and run it up under through the parking brake slot. You can give that a yank in times of need. This however is not recomended for full time speed. Your engine will not last too long. I too have had your problems and feel your pain. I'd love and XUV but am stuck with my 4x2. It is 4 miles from one side of the farm to the other and its a long ride if you have to do it in one shot. The 4x2 is built to last not for speed unfortunetly.