foampervert

iTrader: (5)

Hiya folks,

I've started this thread so that we can discuss technical stuff about on-road cars (f1, 1/12th, 1/10th touring, mini, fwd, even gp cars)

Do let this be a thread for technical discussions on tuning and driving, do not bring personal grievances here.

Enjoy!

-Alexander

foampervert

iTrader: (5)

Hiya folks,

To kick off the discussion, I've recently returned to on-road and am driving a tamiya ff03. Generally quite happy with it except that the car is a little twitchy and the rear spins out everytime I let off the throttle (even at low speeds).

This is my setup:
Front:
Damper: 400
Spring: white (but I tried grey<harder then white, which made it a little better>)
Ride height: 5mm
Droop: 3mm
Front toe out: 2
Camber: 2
Caster: 0

Rear:
Damper: 400
Spring: fluorescent red (softer then normal red)
Ride height: 6mm
Droop: 0mm
Rear toe in: 2.5
Camber: 2

Using spool
Tamiya b3 tires all round
Tamiya 14t motor
Gear ration: 4.58

Any suggestions? It's hard to drive consistently because I have to be on-throttle all the time.

kerk

iTrader: (2)

Bro, before you change anything, can you try to put in some droop on your rear. You can try about 1mm more than your front droop, so that's about 4mm.

Cheers!!

foampervert

iTrader: (5)

Hiya Kerk,

Won't more rear droop cause even more rear to front weight transfer during off-throttle?

As it is, car works pretty decent except off- throttle... When I go off-throttle, the rear end tends to slide out. No probs when I'm on-throttle, rear end is very planted.

Thanks for the comment though, let's open this to anyone with 4wd/fwd touring car experience... Anyone?

-Alexander

sammies

iTrader: (1)

Wild guess... but i think both of you talking about different things... or rather, probably both of u have different definitions for "droop"...

I think Kerk refering to downstop value.... while alex refering to droop droop (how much chassis lifts before wheels aer off the surface)...

kerk

iTrader: (2)

Hi, Alex you are right about having mass moving forward. With (let me rephrase, thanks Sammies too!) up travel available on the rear axle, when you go off throttle, while the rear rises, but it will not be stopped by the droop's grub screw, rather it will allow the chassis to rise but not trying to lift the wheels off the ground. This will allow the rear wheels to maintain that little more traction.

To start off, what I suggested, it will most probably make the rear pretty planted, but the steering will be kinda blunt. Gradually reduce rear up travel with a quarter turn at a time. Its very interesting to try this. I've always found it very effective.

Cheers!!

foampervert

iTrader: (5)

Hiya Kerk!

Thanks for the tips! After an extensive day of testing at Atalon race track, we've discovered it's all because of the spool... The tighter the front diff(or spool), the more twitchy the car becomes. This may be a phenomena for fwd cars as we have not tested on anything other then our ff03. Swap the diff in and instant tameness.

The car now diff out (loses drive) at turn out due to chassis roll, so we're gonna try to solve that. The car is a world of difference now. Seems spool on a fwd requires extremely careful setup... The diff makes the car what a fwd should be... Super easy to drive.

Zakkie and I are both on very different setups, we'll see if it pays off in the continuing days of testing before Tac.

Thanks again!

-Alexander