sean-- The Quantum sport is great for stock as long as its not the one with reverse. the the guy who was TQ in stock at the last CRL race uses one.

no reverse, just the standard forward/brake quantum sport. will those "worlds" capaciters do anything for stock racing? again, i dont know if i would really need or notice it because i mostly want to race purley for fun, i dont really plan on competing for points or anything. BTW what is so bad about the reverse speedo? i know you cant use it for compitition,but does it hinder performance?

The "worlds" kit dosen't help much for 1/12 in gereral. The reverse does cause you to loose a little performence but not much though.

are there any good web links with 1/12 racing video clips and or pictures of cars and set ups?BTW what kind of bodies are you guys running? i ordered a parma speed 8

Calandra 3.2 diff
 

What's the verdict on how well the new large diameter diff works on the Calandra 3.2.

Is it worth putting it on a 3.1 or is there very little difference ?

My 3.1 diff seems to live quite a long time between rebuilds now that I have engineered a proper thrust race in to it to take the side load normally placed on the outer bearing.

The diff that comes with the 3.2 uses 12 diff balls instead of 6 or 8, so it does last longer, but if you are happy, dont worry about it.

How many balls you use depends on which spur gear you are using. If Kimbrough, then yes you will use 12 balls. The kit comes with Du-Mor gears and they still use 8 balls even in the outer holes.

The reason using the outer holes is better, is that it gives the balls much more mechanical advantage. Moving the balls out in the gear makes them grab the rings better even with less tension on the diff nut. This in turn - A) makes the diff last longer, and B) makes the diff spin smoother and freer.

The small ring diff works very well too. As stormperson said, If you are happy with your current set up, then don't worry about it. Spending $45.00 to "fix" something you are happy with, may not be worth it. On the other hand, if you decide to get the large ring diff, I'm certain that you won't be disappointed.

john

stormperson , johnnywhopper

Thanks guys - I'll run what I have until I break it.

Then look at the 3.2 diff.

Bob would you mind sharing how you improved the thrust bearing to take the burden of the side loads? I'm interested because before I switched to the rc4less ceramic bearings I ate the outside hub bearing constantly.... um, of course it was because they were all defective since I NEVER hit boards or anything unless I'm hacked... oh, and I NEVER hit anyone else's car; they always hit me!!! :lol::lol::eek::cry:

BigDogRacing

I found a local supplier of bearings and bought a thrust race which has 4mm ID, 10mm OD and is 4mm thick. Cost was £ 5
( $ 8.40 )

Next file off the little lip on the cone which locates the spring washer.

Put the cone on the axle reversed ( large end to the bearing ) which will put load on to the outer race and not the inner race.

Put the thust race on the axle and follow it with the spring washer

Then use a narrow TC3 alloy wheel nut ( Trinity supply ) to fasten it all together.

Because the 10mm dia thrust race is smaller than the hole in the wheel the wheels still go on and off as normal without stripping the diff.

Diff is now really free, The spur can not be made to slip with your thumb and lasts for 4 meetings without any maintenance.

Thrust rece has been on the car for appx 12 months now and just needs a clean each month.

Very nice Bob! To be honest I have never thought much about the load that is put on the outer hub bearing- it's ridiculous to put a opposing vertical load on a bearing made to handle side loads ONLY!!! No wonder those bearings eat themselves constantly!!

So you simply purchased a 4x10x4 thrust bearing and installed it with the cone reversed to carry the load straight to the outer hub bearing and housing. Nice. Obviously you had a minimom amount of threads for the axle nut; I wonder if a shorter cone washer would help or even milling a little off the original washer?

I'm calling Memphis bearing supply right now!!! LOL

Bob is your thrust bearing the kind that is prebuilt like the Tamiya diff thrust bearing or is it seperate pieces?

Bob my local bearing supply doesn't show anything smaller than 4mm ID- could you find the brand name and or the application of the bearing you have? THANKS!!

BigDogRacing

The thrust race is pre-built - It has two grooved plates and the balls are in a brass cage.

You can't thin the cone down any further because the thrust race will touch the main axle ( It sits over the threaded part when assembled ) Using a 3.1 axle or an IRS axle there is about 1/8" of thread showing past the thin nyloc nut when assembled.

Never had one come loose on any axle yet and I have converted over 20 axles for friends.

BigDogRacing

Have a look at this site -

http://www.ball-bearings.biz/uk/cata....php?subtype=8

This is where I got the thrust bearings

bob
,
can you post a pic of your axle upgrade

casey