I'm new to the r/c world but just bought and hpi E10 monster energy drift which I have just made a few changes to. Replaced 27t motor with firebolt 15t. 5000mah 6cell batt., and ditched the drift tires for sport tires. also replaced rims and bodyshell to F150 flareside. I want speed more than anything just to bash at home but on a really tight budget. My question is with the firebolt 15t which pinion gear would be optimal as now it has a 48p 22t with 65t spur gear. Lower turns is supposed to be faster but when I still had the 27t motor I could run a 33t pinion and the top speed was alot faster than it is now. Any recommendations? And don't say brushless as it isn't in the budget.