Question: for those running a gear diff with AW grease, have you found the need to rebuild the diff because it loosened up? (or have i built in incorrectly?:blush:)

It can change two things..

When turning, the rear will have more grip, but softening too much can cause the tire to skip, losing corner speed. You want just enough to keep it planted, but not skipping.

When accelerating, more weight will transfer to the back of the car, leaving less grip for the front tires to steer and accelerate. You'll want to minimize this as much as possible.

HEY TONY!! :)

I've got the suspension changed 'round on my first RWD M03 conversion. A couple questions:

1) did you really need to cut away the original servo mount/body mount structure? Looks like mine will clear the body (at least the Alpine I'm mocking up).

2) to mount the shocks at the front you discuss shortening the pivot pin and using the same hole for the lower shock mount. It's looking like I need to trim back (or remove outright) the actual lower shock mount from when that arm's on the rear (where some might argue it belongs). Was this your experience?

3) For shocks I had a set of ally shocks. Removed all (3) the o-rings from the inside and installed them with the fourth o-ring on the shaft outside to serve as travel stops. Really looks like I could use one more o-ring to extend my travel stop. Need to add some pre-load clips so the springs (long) support the car. Again, does this seem to mirror your experience/expectation?

This first one will get the nice lightly-used Alpine body. I'm trying to get the mounts to pick up the holes already in the body, so this will take a bit of jiggering around. Looks like the front will be solved with yet another pair of M01/M02 front (straight) mounts. I'll have to dig through my rear mounts...the standard M03 rear mounts (on the rear mount supports I haven't cut from the chassis) don't have quite enough "dogleg" to pick up the holes. Close though.

Thanks,

Scottrik

wheel stuttering
 

Try measuring the play in the wheels and add some shims, to take out play.

You have done fine, but probably have flung the AW off of the gears, into the open void in the gear diff.
Or the viscosity of the grease has changes in the hot Orange County weather. :blush:

SCOTTY!

Questions, questions, questions....

I cut away the servo mount...not for clearance, I only did it so it'd look cool! Otherwise at first glance (or 2nd or 3rd) it'd just look like a normal M03. So that's the only reason why I cut it off.

The front shock? No I didnt need to cut the original lower mount off the arm although it is a REALLY close fit I'll grant you. Take a look at the pic and that's what mines like. Close, but doesn't quite touch the lower spring collar. You could just trim the front edge of the old lower mount back by 3-4 mm that'd sort it maybe?

The rear shocks? No rocket science here. All I did was keep playing until I got the arms to sit level. Which is pretty much what I do on all my cars.

TG

THAT'S the solution on the front shock lower mount. I knew I needed to order in some mount balls...didn't realize (or remember) they extend out that far.

I'll rob a set from another project so I don't have to wait while Tamiya get around to delivering them.

Thanks!

Scottrik

Hey Tony,

Those shock mount balls you show...do you have a Tamiya part no. or what chassis kit they'd be from? Can't find 'em digging around on Tamiya USA, etc.

Oh, do they have a threaded stud or do you use threaded rod?

Thanks again. If I can get this one done I've got three to go. Had a Datsun 510 to do and RC Mart got me my NSU and Subaru 360 bodies WAY faster than expected.

Scottrik

Scott,

They are the steering arm ball joints from the mini ;) No idea what the part number is though.

Tony,

Can I ask why is that locking up the diff's an added advantage over a tighter locked ball diff? and I see that it has added advantage on bigger tracks..

My assupmtions are that ball diff's are smoother round the bends and the gear diffs are a wee bit squarish when it comes to tight bends.


Thanks.

Aye yai yai...

I was HOPING there was a way to buy packages of them rather than how they come "for the Mini's" which is in the Metal Parts Bag A. They're referred to as part MA16 there. There are 2 in the bag...need 4 for the front shocks times (ultimately) 5 cars. Ten parts bags are a little much. Sure, I'd like a few extra diff washers too, but 20 of 'em is probably a bit much.

Does anyone know how to get just the ball studs? Or something similar?

Thanks,

Scottrik

I was able to order some of these from my LHS. They're part #9805825. Don't recall how much they were, maybe $2 for 4 or 5 of them? Here they are on Tamiya USA.
http://www.tamiyausa.com/product/ite...uct-id=9805825

Rally tires for a Mini... I'm turning my M03 into a rallye machine. Using the Tamiya rally block tires, cut to fit a Mini wheel. If you've done this, have you used an insert? Or do you go insertless? I glued one tire to the wheel with a Tamiya 60D hard foam insert in it... it was tough getting everything to fit.

Yep, they're the ones Scott. I was lucky, I got a job lot of a whole heap of them at one stage from some shop that was closing down. So I just sorta had them at hand.
I cut the hinge pin off so that there was enough room to screw the ball connector in. I epoxied it as well for a bit of security.

You don't really need inserts with cut down rally blocks. They're so hard that the insert has no effect at all. However....you may want to reconsider... We've found (well we're 99% certain anyway) that the rally blocks have such tough sidewalls that there's no 'give' in them at all and all the shocks are transmitted straight through to the drivetrain, and then...BANG your internal gears go. Yet the guys running RC18 tyres (specifically Proline Mini bowties) have no gear problems at all because the softer tyres with full foam inserts absorb a lot of the shocks.

You'll find that ALL full-size FWD cars all run locked diffs in racing. Its just a fact of life that with 2 wheels driving at all time, the things just leap out of the corners better... And no matter how tight you do a ball diff, it's still not the same.

Actually, Tony, you are incorrect on the locked diff for full-sized FWD racers. Those are really only used in drag racing. Road racing cars that are FWD use limited slip diffs. These are not fully locked and are able to have some differential wheel speed. The reason for this being that a FWD car with a locked diff can be very difficult to turn, especially in low-speed corners, due to the fact that both wheels will turn at the same speed. Cars with that set-up can be a real handful to drive. Basically you are fighting the steering through every corner as the inside tire hops and skids around the turn. Generally, a limited-slip allows you to steer through the corner easily as an open diff, but transfers full power to the wheel with the most grip and a percentage of the power (based on how the LSD is set-up) to the wheel with less grip. This basically means that you get full power to the outside wheel and a percentage of the power to the inside wheel. The result is that you are able to maintain corner speed through corner entry and apex as well as launch hard as you accelerate out of the turn. I've driven a FWD racer with a properly set-up LSD and it is infinitely better than one with an open or a locked differential...

Ok, now back to our regularly scheduled programming...