AS for the gearing issue first what type of motor are you running. I am running the stock 16,19 and 43,47 my car seems to top out around 165-180 with those gears. The track I run on is very tight so the stock gears are great. But I have a place that I go and have marked 150 then 175 then 220 ft so I can see where my cars top out at. I would first look at your clutch set-up and make sure it is correct sounds it might be a little loose and you are never getting the rev's out of the motor to pull the straight. Learn that from nats. last year with the mtx-2. If that is ok then check your needle setting for either being to lean or to rich. Try going back to stock setting and set your idle, then top end, then bottom end and see if that helps. Let me know if that helps if not I may have a few more suggestions