Hoping for some gearing help .....

I just completed the build , old 3.3 Revo roller .

I used the Titan 775 and EVX-2 , homade motor mount nothing special wanted to keep it cheap . the nitro transmission had a 40T spur on it so I changed that to 36T , and I'm using a 13T mod 1 pinion . Right now it has slow speed on 4s lipos , I was shocked , or maybe that's all the Titan 775 is capable of ? I'm thinking of gearing it higher , maybe a 17T pinion . right now it has the sped of a brushed erevo with the twin 550's using 8.4 nimhs to give you an idea .

I figured the lipos would wake that 775 up .

I'm just not familiar with the tranny ratio on the nitro revo , then converting it over to electric , what's safe ?