Pumilio Design gear differential for TRF501/511 and DB01/DB01R
 

Just installed my gear diffs on my TRF501. The diffs are manufactured by Pumilio Design. I have not yet driven them, but they feel very smooth, hopefully they will perform too :woot: On the down-side, at least on my car (TRF501) the front upper deck needed some cutting for the diff to fit, but at least on my opinion, it is not that big of an issue.


Pic.

http://lh5.ggpht.com/_CbsnmK9PWPY/TE...milio_diff.JPG

The price is 120 eur for one diff, which equals to slightly more than a new ball diff made with ceramic bearings and balls.

How much were they Mof? and who do i speak to about ordering some?

Im liking the look of those, seriously would be interested in a set if you have more details :thumbsup:

looks good

I also want them where to buy:thumbsup:

Also interested in where to buy :)

Pm sent.

Made in Finland?

The casing is.

Internal gearing is from an Xray NT1. Outdrives are custom machined Tamiya TRF501 oneway outdrives and the pulley is also a custom machined Tamiya pulley.

some details on price and where to order them from would be nice.

look nice!

The website is a bit of a struggle and I can't see them on there at all ........... how do we order? :(

PM sent.

They feel even nicer :thumbsup:

Too bad I have not yet had the opportunity to test them on the track :cry: But I've heard good things on them from some other drivers.

The price is updated on the first post.

120 euro?

surely that is a mistype.

a set of gear diffs is going to cost 1.3 times more than a db01r?

No, it's not a mistype.

I am not the one who makes them, but there are a few factors to this. Firstly, the need to buy the gears, pulleys, oudrives etc for the diffs. Then a quite a bit of custom machining (outdrives and pulleys need custom machining), then there is the whole diff case that needs to be manufactured and so on. And the production rates are low, it is not a mass product.

If you go and buy all the necessary stuff to make a ball diff with ceramic bearings and balls and TRF501/511 outdrives, it will be quite expensive too (the prices are rounded values):

Outdrives, 23 eur
Ceramic balls, 10 eur
Ceramic thrust bearing, 10 eur
Ceramic bearings, 10 eur
Screw and nut, 10 eur
Pulley, 4 eur
Diff plates, 4 eur

The cost comes to around 70 eur for one. So yes, the gear diffs are more expensive. But they are also a different product compared to the mass produced parts that you use for the standard diffs.

And I think it is not right, or fair, to compare the price of an entry level model like the DB01R (which by the way costs around 300 eur in Finland with no tires, wing or body, so in reality around 370 eur with the necessary stuff... taxes, gotta love 'em...) in Hong Kong etc to something custom made, like these diffs.

PS. If you look at the price of mass produced carbon or alloy parts for TRF501/511, you also see a trend of not-as-cheap-as-db01r-would-have-been :) Rear front or rear lower bulkheads. 30 eur. Each (so 120 eur total for the car). 60 eur for the chassis (one piece of carbon fibre), oneway 45 eur, alloy hubs 40 eur / pair and so on, even the body is 45 eur. The diffs don't seem as pricey as if you compare them to the plastic parts of the db01 as if you compare them to the price of the parts for the TRF models...

What are the advantages over ball diffs?(i had to ask)

No maintenance whatsoever once the right oil is found. If its manufactured (and build) correctly...

I find it very hard that there is hardly any maintenance with gear diffs. Just ask any durango owner, even the spec r owners. Tell me a gear diff that doesnt leak!

Ran a couple of runs today with the diffs. I really, really, like them. :thumbsup:

If durango diffs leak often / a lot, that does not mean that all of them do...

Maintenance free is a bold thing to say, so I'll just say that a lot less maintenance. 100% slip free, which, at least in theory, translates to more precise throttle control. Consistent performance, no need to readjust the diffs. Easier to setup correctly than ball diffs.

I am not saying one can't make a ball diff as good as a gear diff. But I can't, and I can say that my diffs have never been smoother while being slip-free than they are now. :thumbsup:

When comparing the durango diffs to 1/8th diffs, its easy to see why. The "o-ring" (if you can call it that) simply isnt up to the task. It dosent help putting washers in between partly because of the design, but mostly because the ring dosent compress like conventional o-rings. 1/8th diffs do not leak because they're build slightly different.
I dont own a durango, but i've seen the diffs up close and personal and I'm sure its only a matter of small tinkering to make the seal work 100%.

The pink DB01R in this vid has these gear differentials, but as the track is very slippery, I am not sure if the video shows any advantage or disadvantage of the diffs... but I decided to post it anyway :woot:

Hey Mof

I personally couldn`t tell but nice driving and loved the track ! it had some different kinda jumps i haven`t seen before :woot:.

Keep us up to date with how the geared diff holds up and perform!

Cheers

Andy

yeah 120 euro per diff is off the chart, i agree it can be justified how they arrive to the pricing, but no way would i even think about it

that vid shows just how well the DB01R's jump that thing just flies over that large jump up the back and lands nicely on the down ramp and was being driven very well, my one is probably the best car ive had in terms of jumping

apologize for going off topic, but since your on the subject.....

what weight, whether lipo or plus additional weight is a good balance for the db01r?

currently using around 290gram lipos

Yes, the price is high, and it is everyones own choice wether they want to spend the money on their car or not. I am quite happy with them, no leaks so far, and they are currently in my TRF501, and if I were to buy a DB01R, I would just swap them there, and if I were to buy a 511, I would just put them there. Pretty versatile diffs in that manner. And to lower the initial cost of purchase, I sold my old diffs, which I really don't want anymore. :)

mof, tell you contact to check his email. Havent got a reply yet.

I believe he's been on summer holiday. Hopefully he'll answer you soon.

all i tend to do is match the weights left to right, with a 290g lipo, ur electrics should add up to the same amount on the other side of the car, if u do get the other side to balance up to 290 ur car would end up being around 1560g depending on a few other factors. mine started out around 1590g so i put lighter electrics in and a lipo the right weight to balance it up and its now 1515g,which is just above our legal limit here, lightening up the car doesnt seem to have affected the handling, but the car jumps and flies through the air even nicer than it did before

Hey Mikey, I thought legal weight for 4wd was 1600g

Although this is offtopic, I'll comment on this anyway...

The motor (the heaviest of the electrics apart from the batteries) hangs out quite a bit on the DB01/DB01R, so just having them (lipo and the rest of the electrics) weigh the same does not mean the car is balanced out.

If I remember correctly, the car on the video I posted has around 290g lipo + 60g additional weight on the battery side to balance the car left/right.

Where can you order these diffs? Thanks.

You got a PM.

Thanks buddy!:thumbsup:

I preferred gear diffs in my zxr in the 90s on high grip surfaces as they worked better and made the car feel easier to drive. I used different grease thicknesses to better suit the surface. Strange that gear diffs are coming back in a big way. Still way over priced but look great.

Just in case someone ordered these (or use some other gear diffs), remember to readjust your slipper. Remember that gear diffs have zero slip so they will cause more strain to the belts.

Is there a site to place an order of these diffs?

You got a PM.