The new DarkSoul 7075 Billet Aluminum Differentials are done….. finally. Seeing as how the Losi 5ive is currently the only large scale (non-clone) on the market with a plastic diff housing, we felt it was only a matter of time before the big engines were going to start eating up the plastic housings (much like the HPI Baja, before they switched to metal housings), so we started working on a design, but as we ran our Losi 5ive, and we started to see others having issues with the front drive cup / dogbone getting extremely hot, we sort of went back to the drawing board a bit to try and see if we could do something about the heat.
There were several iterations of the center diff , radial fins, interrupted radial fins, vertical fins, so on and so forth, and as I got more into the design, and remembered (duh) that we had 5 axis machines next door, we went with sort of a turbine look, that actually pushes a little bit of air back across the spur gear as well.
In our testing, we found that (depending on setups) we would see temperature drops on the diff housing itself (as compared to stock housings), as much as 20-30º, but what really blew us away, was the front diff drive cup, we saw temp drops averaging 30-40º , but sometimes as much as 50-60º. The 5ives with stock diffs were getting up to 180-205º (hottest I saw of the day) at the drive cup, and when run side by side, for the same amount of time, 5ives with the billet Turbine Diffs were easily 30-50º cooler on average, and as mentioned, sometimes as much as 60º cooler.
So why does this matter? heat is ALWAYS the enemy, a cooler car (any part of it) is a happier car, keeping the diffs and drive cup/dogbone cooler, means the steel will retain its temper longer, and therefore stay stronger and less prone to wear. The diff fluid will stay cooler, and therefore remain more consistant in its “diff action”. As well as the cooling effect, you get the strength of the 7075 aluminum, it will not bend, flex, or warp from heat or stress of big HP engines, and since it cannot flex like the plastic, they won’t leak either when properly assembled with a new gasket and form-a-gasket on the diff cap.
Why 7075 ? With a maximum tensile strength approaching almost double the max tensile strength of 6061 (83000psi compared to 45000psi), why wouldn’t we? Using such a strong (and light) material for this application will ensure that these last the life or your 5ive.
Street Price -
Front or rear – $140 (will work front, rear, or center)
Center – $160 (will only work in the center)
Available now at TGN –
Front / Rear Standard Diff housing – Billet Diff Housing for the Losi 5IVE-T
Center “Turbine Diff” housing – Diff Turbine Housing for the Losi 5IVE-T