I've just about read through most of this post and was curious as to what top speeds you are achieving now? As far as Top end an acceleration go.....you can't have both (without spending for it (in terms of getting a bigger/better engine))
So you have to ask yourself is it worth it to modify your engine or buy a new engine, just to be the king of your parking lot.
Gearing will help you slightly , but as those other guys said the limit of the engine will not allow for much more improvement. Believe it or not there are plenty of .12 engines that would cream your engine, simply because they rev much higher. The torque your engine produce is awesome, which is great for acceleration, but for top end you need more RPM's
Some things you can try along with your new gears (if you buy them...is getting a longer stinger for greater top end speed) Also don't for get to adjust your shifting points on your two-speed to get the most out of your current engines RPM's
Also get a nice aero-dynamic body for your car...Hell..get a 220 Lola body. I'm sure your friend will start crying foul if you came out there with that
Lastly, consider getting a bump box for startign your car and lose the pull-starter...that alone could add a couple hundred RPM's to your engine. (less rotating mass)
Lastly the 4tech 3.3 is really .20 engine with mad torque...meant for the Revo and Jato off road vehicles. I've seen my friends 4tech ripe tires right off the rims and destroy gears, clutches and transmissions.....you name it
, but the fastest he's gotten his gotten it go is 67.8 mph (clocked by police radar gun) Close, but not 70mph. He's using 33% Traxxas fuel too.
If you want a mill that will run him down....I've heard great things about this engine
. Others on this forum can attest to it greatness.......and.......wait for it.........its only............$175