I have enough experience with Maxx trucks on 3s LiPos that run 40+mph. And I can say that it is very hard to do. You must drop a ton of weight and gear properly. I was able to keep my temps in check but others have had very different results. I run a VXL system on a single 3s LiPo to exceed 40mph. My V-Twin runs in far excess of 50mph on a pair of 3s packs in parallel. Here is a video of my light weight 3906 E-Maxx on a Venom 5400mAh(junk) LiPo. I have hundreds of videos so if you want another, just ask.