Center Diff?

[MacII]

Hello,

Does the E-Revo have a Center Diff? If not, is it like the Nitro Revo where you can get an upgrade part do add one?

DM

[Just go Play]

No center diff on the e-revo and there is not one that will fit the new tranny at this time.

[MacII]

"At this time" - Hmmm...do you know something? Is there room for one?

[Shelby VNT]

I have my doubts that Traxxas would do a center diff for the E-Revo or new E-Maxx. Reason being, is with a center diff comes dual brakes, and with dual brakes, you'll be looking for another servo, plus a spare place to mount it. Then you'd need a Y-harness off the speed controller to run that servo, and before you know it, things are getting complicated. I wouldn't say it isn't possible, but it's pretty unlikely.

[bmoney]

No center diff on the e-revo and there is not one that will fit the new tranny at this time.


there is a center diff for this truck, not sure where you got your information

[J3110]

I guess if you're crafty, you could always make one. Output gear + ball diff = center diff?

[MacII]

there is a center diff for this truck, not sure where you got your information

I realize Traxxas only has their "teaser" pages up but do you have any links or proof that there is either a CD installed stock or a CD upgrade?

Thanks,

DM

[bmoney]

I realize Traxxas only has their "teaser" pages up but do you have any links or proof that there is either a CD installed stock or a CD upgrade?

Thanks,

DM

I have reliable resources. make no mistake this truck was built to race and designed by a racer.

[MacII]

Are you saying it comes with the CD stock or that it is an option?

[bmoney]

Are you saying it comes with the CD stock or that it is an option?

you have a pm

[bmoney]

I imagine it would be an option unless they come out with a complete race version like the platinum.

[Suicideneil]

I'd like proof too please....

I know wallot made a custom CD for the old emaxx tranny, but there is nothing for the new tranny....

[Just go Play]

If I am incorrect about this then it is only because it has not been announced yet and nobody that I know of has done a custom install of one in the new emaxx tranny. And as neil mentioned trying to add dual mechanical brakes would seem to be at least a challenge (nothing is impossible given the right resources) with the new chassis.

If you are correct though that a cd is in the works for the new tranny that would be a welcomed option by many folks interested in racing the e-revo.

[MacII]

(Mechanical) Brakes are not a requirement. I run a E-CRT which has a Center Diff and it runs fine with Electric and no (mechanical) brakes.

[Just go Play]

No they are not a requirement but it is definitely nice to be able to set front to back brake bias.

[Suicideneil]

True and true. My only concern will be that the CD offered by traxxas will be like the nitro revo CD- a bit weak. Wallot and another guy who made a custom line of CDs used a 1/8 buggy diff as the basis for their design- 6 spider gears. I hope traxxas is taking note...

[Just go Play]

No joke and don't even think about using the revo CD if your running a decent brushless setup. It just is not possible to control the diff action... all you get is spinning front wheels.

I have the cad drawings for the modified 1/8 CD that those guys fit in the revo tranny, but I think it would be easier just to build a buggy style mount for one and ditch the tranny altogether.

[Super RC Driver]

I don't see why Traxxas would want to make the E-Revo just for racing. I think it's better that it doesn't come with a center diff because it be a little cheaper. :)

[outkast187]

I really dislike the CD in the e-revos, I tried mine at all weights and hated it. I went all the way to 500K in the CD and it just unloaded and absorbed way too much power. Im running one now with 3905 trans and its 100% better.

[Shelby VNT]

(Mechanical) Brakes are not a requirement. I run a E-CRT which has a Center Diff and it runs fine with Electric and no (mechanical) brakes.

Riddle me this, Batman - what is that center differential doing for your model if you don't have independant front and rear brakes? :D

[J3110]

No joke and don't even think about using the revo CD if your running a decent brushless setup. It just is not possible to control the diff action... all you get is spinning front wheels.

I have the cad drawings for the modified 1/8 CD that those guys fit in the revo tranny, but I think it would be easier just to build a buggy style mount for one and ditch the tranny altogether.

Word.
I am guessing the reason for the tranny is, what, gear reduction?
Aside from that, I don't see the reason for adding more weight and complexity to the driveline when my TC3(and apparently most if not all 1/8 scale buggies) just has the spur mounted directly to the driveshaft putting power to the front and rear diffs.

[MacII]

Riddle me this, Batman - what is that center differential doing for your model if you don't have independant front and rear brakes? :D

Vast improvement in cornering. Better acceleration, less wheelies, overall a superior handling vehicle vs a solid center. I'd admit that braking is not improved, maybe even a little worse but heck, I'm a racer, I'm always on the throttle! (mostly kidding)

DM

[Daytona675]

If the CD is to distribute power having one braking force(motor only)its not doing its job to the fullest. So when braking its the same amount to the wheels and give A little more to the planted tires. But with Front and rear braking when the front grabs a little more before the rear brake the power goes mostly to the rear for traction and when letting off evens it back out to handle better. Again my i remind you this is one mans opinion:D

[ntgeek]

I read in another thread that included comments by a Traxxas employee that there will be a CD kit for purchase.

[strangersinspac]

I read in another thread that included comments by a Traxxas employee that there will be a CD kit for purchase.

Yep... I read the same thing.

[MacII]

Guess it is official:

http://www.buytraxxas.com/product_info.php?cPath=1_1675_1658&products_id=3013

5614: Differential kit, center (complete for E-Revo & E-Maxx (model 3905)) (assembled with 100K oil) (use only with single speed transmission)
$39.00

[trx33]

Guess it is official:

http://www.buytraxxas.com/product_info.php?cPath=1_1675_1658&products_id=3013

5614: Differential kit, center (complete for E-Revo & E-Maxx (model 3905)) (assembled with 100K oil) (use only with single speed transmission)
$39.00

Nice Find!!!

[Sir Slide Alot]

If you use the reinforcementplate that come's with the newer E-MAXX/E-REVO diffset the diff should lock more under braking then onpower.

This would give you good brakes without disc brakes, yet still the diffaction is there when onpower or freewheeling.

[DeMoN72]

I have my doubts that Traxxas would do a center diff for the E-Revo or new E-Maxx. Reason being, is with a center diff comes dual brakes, and with dual brakes, you'll be looking for another servo, plus a spare place to mount it. Then you'd need a Y-harness off the speed controller to run that servo, and before you know it, things are getting complicated. I wouldn't say it isn't possible, but it's pretty unlikely.

Good point! I didnt think about it that way. That would make it almost impossible. Knowing Traxxas, they'll think of something! :cool:

[Shelby VNT]

Vast improvement in cornering. Better acceleration, less wheelies, overall a superior handling vehicle vs a solid center. I'd admit that braking is not improved, maybe even a little worse but heck, I'm a racer, I'm always on the throttle! (mostly kidding)

DM

Better acelleration? How? The center differential is just another place for the power to unload to the wheels with the least resistance, like any other open differential. Under hard acelleration, the front tires are going to be spinning and wasting power, while the rear, as the truck squats, will have better traction, but more power will be going to the front end, because it is light. Spinning wheels don't acellerate. They waste power and fractions of a second.

Less wheelies, definitely, but why? For the same reason as above. The power tends to get wasted to the front end, which unloads. Again, wasted power, spinning tires, and the rear end, which has better traction, is not putting down as much power as it could.

Vast improvement in corning? Only if the brakes are set up for the driver's and track's liking. When you aren't on the brakes, the truck isn't going to corner any better, in my opinion. Without a center differential, power is split 50/50 to the front and rear differentials. With a center differential, power can be split a lot more, depending on the fluids. It could pretty bad. Worst case senario, you'll have one front wheel unloaded and wasting all the truck's power, while the other wheels are just along for the ride. That doesn't help you out at all.

Better braking, probably. Braking is much more tuneable. You have the ability to control front to rear brake biasing, which I think is the whole point of having a center differential. It allows you to lock the rear brakes up, if you like, and put the truck into a nice slide, which almost gives you the effect of over steer. In this way, the truck is going to corner better, because you can it can be set-up to enter turns quicker, and rotate about it's axis, if you do a nice job setting up the brakes.

[MacII]

Better acelleration? How?...

Yikes, long post. All I can say this this, years ago when I had an E-Maxx there was a guy who also had an E-Maxx with a custom Center Diff. His truck handled better than ours (when I drove it). Now that I race Electric Truggy, I know that 50K in the center make the truck perform fantastic. Too light and it's not so good, too heavy and it seems to spin out too much. It's a world of improvement from my old E-Maxx but then again it's a very different truck so we are not really comparing Apples to Apples here.

Fast forward now to the Revo and E-Revo. The general feedback from the nitro guys who do the Center Diff is that it improves the truck. I'll find out first hand when I get my E-Revo, I plan to run it with the stock tranny for a while and then upgrade to the Center Diff. THEN I can truly answer your question based on LAP TIMES. Till then it's all conjecture.

DM

[scramblermaxx]

center diffs do not make vehicles takes off faster- in fact they actually slow down the accelaration in most cases as many have pointed out because power is wasted in the spinning front tires.
BUUTTTTT..... having a center diff vastly improves handling. a vehicle without a center diff is much more likely to spin out under hard acceleration on a track- a vehicle with the center diff is more controllable thus you can run faster lap times and not spin out so much. the power is made controllable with a center diff.

[Patrick 86]

My truggy with a center diff accelerates better than my e-maxx with the same power system did. The front wheels in the truggy do spin on take off, but you can still hold the throttle. The e-maxx would just do a wheel stand even with everything lower than stcok. Once it wheel stands you have to back off the throttle which lows you down.
Obviously you have to find the right center diff oil for your use. Not too light so the front wheels just sit there spinning, but not too thick so you wheel stand. To me center diffs are the way to go.