Horatio

It's really very clever and relies purely on gears and mechanical means to stop the low traction wheel from spinning. No electronic sensors, or brakes or clutches - just gears/worm drives. On 3 diff cars it makes a lot of sense - otherwise you can potentially end up with 1WD on slippery tracks. Hardly ideal, no matter how easy they are to keep within the lanes with all the power going to 1 wheel with no traction. With actual LSD, more power gets to the ground where it's needed. It's down to the driver to harness all the extra go! Lol.

Horatio

New Autocad, 3d modelling, virtual prototyping, new materials to work with - I'm sure there's a way to make a bullet proof 1/10th Torsen diff that's still light enough to be useful.

There is definitely scope for them in 1/10th.

It's just the tool up cost I guess. If enough people wanted them, it's the sort of thing that crowd funding might make a reality. Or perhaps Tekno/Losi/Hobao might take a punt - you never know. Stranger things have happened.....

Horatio

So Torsen and Salisbury type diffs should definitely still be classed as variants of gear diffs, as both are purely mechanical.

waitwhat

iTrader: (4)

If you want to get rid of the goofy handling of a center diff you have two options:




Those special diffs for 1/8th scales are ridiculous. There is a reason nobody uses them. Pro drivers could use them without the $$$$ and they still don't run them. What does that tell you? There is no way I'd want to spend that much money to add a bunch of failure points and complexity to my car.

Horatio, have you raced a 1/10th 4wd buggy with a center diff? Have you tried the same car with a slipper instead of the center diff?

Horatio

Read the previous posts - the answer to your question lay within. Always used a slipper, as 1/10th torsens are only hypothetical at this stage.

waitwhat

iTrader: (4)

I didn't ask if you'd run a torsen center diff as obviously those are not available for 1/10th scale. I was asking if you'd run one of the multitude of 1/10th scale cars that have a center diff (HB, XRay, AE, Tekno, ect) and run it back to back with a center gear diff and a slipper/spool.

See this is another example of how your lack of recent racing experience means you don't have anything but a theoretical say in the matter. For the last few years many shaft drive 1/10th scale 4wd cars came with center diffs as standard. The newest generations of cars have a slipper standard as the dynamics of a 1/10th scale electric 4wd buggy mean that a center diff just doesn't work well on high grip surfaces.

Horatio

I've categorically and comprehensively listed the cars I've raced. I have years of track time with 1/10th and 1/8th where suspension geometry, tyres, shock tuning and a multitude of other things still apply as much today as they did then.

Check the fast guys and who do all the techie stuff for them in the pits. Maifield provides the thumbs and the feedback.

So respectfully, you are entitled to your opinion.

Centre diffs were not used on any of the cars I raced in 1/10th, only slippers which were on every car I raced, 2wd, 4wd on or off road.

At present, we see gear diffs and ball diffs being used in 4WD and 2WD.

You may only base your opinion of what constitutes as good based which 'pro' uses what and how recently they used it. That's cool - that's exactly how the brand's want you to think.

Torsens are an as yet, un-tapped area of opportunity for 1/10th - it's only a matter of time. You are quite wrong to conclude that because less people ran Torsens, they are less effective than open gear diffs.

Horatio

To be clear, if I had the option to run a centre torsen on a shaftie, I would - provided I still retained the option to use a slipper clutch in conjunction with the diff. With electric classes, the way electric motors deliver their power, slippers are a good idea.

waitwhat

iTrader: (4)

I only care about how a parts configuration works on my car. I look to those faster than I am to see what direction they go, but I am by no means beholden to what they do. For my HB 4wd I built my own slipper as the unit from HB was vaporware available only to one or two team drivers. I had already arrived at the necessity of a slipper based on my own testing, and my desire for a more "normal" feeling 4wd. I let lap times dictate what I use, just like the pro drivers. If torsen diffs produced faster lap times, pros would use them. They get paid to go as quickly as possible, there is a reason they use what they use.

Do you have any experience with electric powered 4wd cars with a center diff? Do you understand the vehicle dynamics of an electric powered car are vastly different from a nitro powered car equipped with a center diff and a clutch? The instantaneous full torque of an electric motor and a lack of clutch makes for a car that is very dynamic when driven at the limit. Overstep the traction limits a tiny amount and the car starts to do crazy stuff. Get rid of that center diff and the car becomes much more predictable at the limit.

Horatio

I'll take that as a rhetorical line of questions.

I wouldn't run an electric car without a slipper. I wouldn't choose to use a centre diff in an electric car unless it could be utilised along with a slipper clutch as well.

waitwhat

iTrader: (4)

It is not a rhetorical question, there are many electric 4wd vehicles (of both 1/8th and 1/10th scale) where they come as standard with a center diff. Some of them have slippers available as an option (only 1/10th scale), but many of them do not (no slippers available for 1/8th scale as the rc monster "slipperential" is no longer produced and nobody makes a slipper for the Tekno 1/10th scale 4wd buggy either). You don't have any experience with these cars and how they respond when switching between a center diff and a slipper.

Another thing to consider is how a center diff performs under braking forces. A nitro car has adjustable brake bias on the outputs of the diff, but the braking forces of an electric motor must go through the diff. Some electric 1/8th scales have provisions for mechanical brakes, but that is not an option for 1/10th scale. How would a torsen diff work under braking forces? Would it let the front tires lock up while there is no braking forces to the rear? Would the rear tires lock up and let the front freewheel?

trf211

B64 slipper fits in the eb410 with no modifications from what I understand.

posts 2515 in the eb410 thread.

Horatio

Why is this directed at me, like I'm not qualified to discuss Ball Diffs vs Gear Diffs?

I don't need you to explain to me all the 'Roger Irrelevant' stuff to do with brake bias on 1/8th nitro buggy vs no brake bias on an electric buggy etc. Effectively every 1/8th Nitro Buggy/Truggy has a slipper (of sorts) because they all use a centrifugal clutch which inherently slips. But we're not really talking about that.

We're (collectively - not just you and I) talking about the virtues of ball diffs vs Gear diffs and we can't have that conversation without mentioning Torsens. Torsens are relevant to the conversation. Your rambling opinion as to why my opinion doesn't matter - like some kind of thought Nazi - isn't.

I still qualify to talk about these things even if I had no thumbs to begin with. Get over it. Or maybe I'm quicker than you driving with my toes - we'll never know.

Likewise, I don't know anyone who's tried to use a Torsen in a 1/10th buggy. But I see no reason why they couldn't be developed for them. That conversation is also relevant.

As a side note - I'm literally 'so old' I still use 3VC stick radios. I prefer them. Does that make me even less deserving to comment? Lol.

Going from what we know though, Torsens worked well. Their popularity was not great in the good ol'USA because of the cost and type of tracks you guys race on.

Track fads change, as do designs of 1/10th scale buggies.

waitwhat

iTrader: (4)

So which diff has produced the fastest lap times for you in back to back testing?

Horatio

Dude - GFY. Have a nice day.