mike_Webb

Interesting...

http://www2.towerhobbies.com/cgi-bin...?&I=LXCKT7&P=7 It does say however it is for the Steel Diff (3918) but list the part number for the molded outdrives (3908).

FEATURES: Steel ballbearing construction

INCLUDES: Two bearings

SPECS: 4x8x2mm IDxODxW


for some reson though my Bushings that I got with my Brand new TC3 are only 1.85mm and my spare busings are 1.87mm wide...so I wonder if the bearings are too thick.

Grizzbob

iTrader: (2)

The older ones(for the steel outdrives) are too thick, but there ARE proper ones(or at least were) for the molded too(it's not case closed because THEY'RE IN MY DIFFS). Unfortunately I don't remember precisely what part number they were, but they DID specify that they were for the 3908 outdrives on the package(& yes, they were from Associated, not an aftermarket company). I also know that they're a bit different from the oens for the steel outdrives because I actually have one of the old bearings in my front diff. When I was rebuilding my diffs & adding in the molded outdrives, I accidentally lost one of those bearings, so in desperation, I used one of the older ones to see what would happen. And as a result, it had a tendency to nearly lock that diff up(because of the older bearing not fitting properly, so it binds). However, it made me curious, so I just left it that way & ran that diff up front(like a spool), & it actually works pretty well like that. It still has some diff action, but it also behaves a bit like a spool(but it doesn't chew up CVD's, because it can still slip in extreme situations), & I'm still running it that way. Seems to work well, & actually gives me a bit more steering than a spool would.....

Bubblestc3

How long ago did you get these berrings for the diffs?

Two weeks ago while at the racetrack, I was helping a friend build a car. While building the diffs, we encountered a problem. the two bushings were about three tenths of a mm too thick, causing the diff to be loose(the ring gear would just spin because of no pressure on the diff balls because the outdrives were too far apart). But as we tried to put the diff in the car, it felt like it was too tight of a fit, and felt like it was binding. Time to bust out the digital caliper! After sending my friend up to the counter to get the correct parts, he got the berrings for the steel outdrives, which I told him to go and take them back and get the bushings. He came back asking if the berrings for the plastic outdrives would be better for the car. I told him that ae does not make any berrings for the plastic outdrives, but he persisted, so I had to go and have a look.

Sure enough, they were for the plastic outdrives, correct width and everything! Although I still do not recall the part number for these berrings, they INDEED fit the plastic diffs!

rinkrat99

Hey GrizzBob

I didn't mean to offend you when I said CASE CLOSED. All I was trying to say was that Associated provided the answer and I think thats fine for me. I will not use the bearings and I really do not need to spend hours trying to find the correct bearing. I do appreciate your insight and I am guessing that Associated pulled the part probably due to some diff's melting.

I am a bit confused when you said you used the thicker bearing and it SPOOLED. I tried the bearings and all it did for me was to expand the outdrives off the Diff gear and therefore gave me no contact to the balls. The wheels would spin freely off the ground but once there was any resistance, the diff gear would just spin without any power to the wheels.

In the future, if you ever find the correct part # or a place to get the bearings, please post it.

Again thanks for your insight

RBLove

iTrader: (90)

Mike D.,

Nice meeting you and racing with you this weekend. See you in a month.

hobbyman_7

iTrader: (9)

Does anyone know of anyone who mill's TC3 chassis's for moving the batteries in closer or does everyone do this by hand?

mistercrash

iTrader: (5)

I know "rayhuang" did it in a recent past. You'd have to contact him to ask if he still does it. Or it can be easily done by hand with simple tools. Just go on my website, click on "MY TOYZ", then select the thumbnail of the TC3 and click on the "battery placement modification" link and follow the instructions.

Good luck

Grizzbob

iTrader: (2)

Bubbles, I got them about 5 or 6 months ago(when I finally decided to stop messing with the aftermarket aluminum outdrives)....rinkrat, I wasn't offended really, just trying to be absolutely clear about it. And I should also clarify about the bearing thing, when I lost one of the newer bearings, I didn't switch them both out for the old ones, just one(so the front diff has one old bearing & one newer one), & after trying it that way it had the effect that Bubbles just described. And since I didn't feel like tearing it apart again, I just tried running it that way, & found that I liked it(like I said, it's kind of like a compromise between a spool & a normal diff). I'm not going to say it's the right thing for everyone, but if you feel like experimenting, who knows, you might like it......

Rory

Flash Gordan - actually, heatsinks are a complete waste of time, in almost all circumstances they make the motor hotter rather than colder, because they cover all the ventilation holes. when the car is stationary they take heat away from the motor, but pretty much as soon as it starts moving they block all moving air from getting to the motor and so make it hotter.

regarding the diff bearings/bushings, AE (nowadays) say bearings cannot be used in the molded outdrives, claiming the diff will not operate properly. I would guess that as someone (rinkrat?) said AE probably used to make a bearing kit for the lightweight diff but discontinued it due to melted diffs/some other problem

Bubblestc3

Try asking at the track, while getting lunch or dinner or something. Most of the people that I race with, that have done this modifacation know someone who can mill it on a mill, or they can do it themselfs.

I did mine by hand, just cause I was board and had nothing to do, so I started to put some different parts on my TC3.

Brant

There is all sorts of material on the web about roll centers and how to find them and what happens when you move them.

However there is not much info on pitch centers, how to calculate them and how they are affected by different adjustments.

Does any on know of a book , website, or ??? that explains how to calculate where the pitch center is located at, or talks about the pitch center and what adjustments affect it?

fast-ho-cars

iTrader: (4)

i have been using ball bearings in my molded diff for some time now. they have to be narrow like the bushing. the ones in the ACER bearing kits are.

a common mistake is to try to use the nonflanged bearings that are also used for 10th pan car front wheels. the inner and outer dimensions are the same as the AE bushings but are too wide. they will cause the diff to be locked up or way too loose trying to get them to work

dasgruvn

k...

for sticky tight tracks...i'm starting to play with suspension setups...what front piece would be beneficial to use on say...socal!...bubbles? anyone, thanks!

currently using F + 0

Bubblestc3

Pitch center is almost the exact same funtion as roll center. But Pitch Center is talking about the longitudinal axis of the chassis, where as roll center is talking about the latitudinal axis of the chassis. On the TC3, it will be hard to alter Pitch center without affecting the Roll Center of the car. You could always use the arm carriers to alter the weight transfer of the car(ie. antisquat/kickup).

Bubblestc3

dasgruvn,

What I have seemed to like recently is the F+0 block, which will give less weight transfer to the front wheels(so less traction on slipery tracks), but quicker response into the corner. When you change the kickup, you are also changing the total caster in the front of the car(the more caster you have, the more induced camber while entering the corner. As the car transfers the weight to the front, and the wheels turn, you will have the tires' contact patch flat with the road surface), which could give you less steering.

Now, depending on what you want your car to do, you could change kickup, or change the C carriers for different caster angles. Dasgruvn, since we are talking about the SoCal surface, try using the F+0 block, with 4degree C carriers. the less kickup will give you the steering/twicheyness that you want, but once you enter the corner there is some extra camber(from having the 4degree caster blocks) that will give you some more control.

dasgruvn, next time you see me at SoCal, stop by and say hi, I do not think that we have met... (will you be there on saturday?)


Chris