center diff in an e-maxx - RC-Monster Forums

_paralyzed_ · **center diff in an e-maxx -** 10.21.2007, 08:05 PM

I'd like to put a center diff in my e-maxx, but without the extra gear reduction of the tranny it's geared to the sky, above 60mph with briang's speed calc. (Thanks BrianG!) It's a hyper 7 diff,48 tooth spur. I WILL run a 2200/kv neu 1515 on 5s, with stock ratio e-maxx diffs(of course aluminum cups, RR gears, fastlane combos) but with the smallest pinion, a 12 tooth, it's geared to fly! So........................................
Should I run an e-maxx tranny, or mod up the center diff like I'd like to do?
Is the neu enough of a powerhouse to push that, or am I beyond the limits?

Thanks for any input guys, I'm almost ready to start my build!!!!!!!!!

squeeforever · 10.21.2007, 09:36 PM

Why not run Hybrids? That would give you some extra gear reduction...If not, you can get as low as a 9T mod1 pinion. I don't think Mike has them, but Tower has Century mod1 5mm pinions down to 9T, maybe 8T if I remember right.

_paralyzed_ · 10.21.2007, 10:35 PM

with an 8t pinion it's at 42mph with the above mentioned setup, so two more questions:
1. is 42 mph too much for a neu 1515 and a 12lb maxx?
2. could I gear higher, or will mod1 gears mesh okay at a 8/48 ratio
thanks again guys!

_paralyzed_ · 10.22.2007, 04:42 PM

bump......................

suicideneil · 04:55 PM

1. its not so much speed, but the gearing that will adversely affect the Neu. So long as the esc doesnt overheat, the motor will be fine unless you go totally crazy. As for weight- if a Hv6.5 can push my 11.5lb Gmaxx around without too much trouble & at about 30mph, the Neu will have no trouble at all- should be a doddle infact.

2. That I cant answer, but you can also use BrianG's calculator to determine the diameter of the gears, and whether they will mesh when used with an Emaxx tranny. There is obviously a limit to how small you can go since the motor can only 'tilt' so far before it touches the tranny/ runs out of adjustment space. For what its worth, 10/66 with 32p gears was about as small as I could go on the Emaxx tranny; use the calculator to determine the diameter of the gears, and then you should be able to see what MOD1 gears will work also.

EDIT: Oh yeah, and get the hybrids, not the combo bulks- you will only regret it when the diffs fly apart and you have to upgrade later anyway.