What is the best way to improve on-power steering?

[dldiaz]

Please share your advice on how to improve on-power steering
(hopefully without losing rear traction).
I am not sure which changes are best for on-power steering,
as opposed to off-power steering (which I do not need).

The model I am currently tuning is an RC10T3,
but I would appreciate general tuning tips for any model.

Here are my thoughts:

1) move front lower shock mount closer to the wheels (more weight transfer to the front wheels?).

2) use the longer, more inside on the shock tower, mounting position for the front camber links (gives more front traction?).

3) stiffer rear springs (reduces rear weight transfer?).

4) use a rear anti-sway bar (also reduces weight transfer?).

5) shorten the wheelbase by moving spacers at the rear hub (allows quicker direction change?).

6) move the battery forward (more weight over the front?).
((I tried this, the downside is loss of rear traction))

[Coelacanth]

Other than adding a front wing, I think you've pretty much covered everything. You've done all that and you're still getting on-power understeer?

[jwscab]

you might also try a little bit heavier oil in rear shocks. rather than change the spring rate, changing the damping will help reduce squat. you can also change pistons, rather than oil weight.

also try tweaking your rear toe-in, less toe-in at the rear will give you more steering ON power.

last, though not sure you can do it with the T3 chassis, is less caster on the front wheels.

[broodenburg]

great question. I'm suffering the same problem. Caster CAN be changed on the T3. Not sure, but i think there are 25 degree casterblocks for the T/B3 (30 is standard if I'm correct).

On this forum I've seen guys using T4 casterblocks with T4 inline axles. I'm only using the T4 inlines at this moment and that doesn't do much yet. Perhaps combined with the T4 casterblocks there is a noticable difference.....

Did you increase camber on the front or even use some lead weight in the front?

[jwscab]

oh yeah, one thing I have seen mentioned on the B2/B3/T3 chassis, is a lead or brass weight inside the front bulkhead to help keep the nose down.

[dldiaz]

Other than adding a front wing, I think you've pretty much covered everything. You've done all that and you're still getting on-power understeer?

No, sorry for the confusion.
I have not tried any of these options, except moving the battery forward.

I don't want to start tweaking everything without a better idea of how it will affect the handling - the truck is currently tuned to the "standard setup" as described in the T3 Complete Tuning Guide. So everything I listed above are options I might try.
(I don't want to change any hard parts -caster blocks, rear arm mounts, etc.- or add extra weight, until I have explored the options above.)

The truck will oversteer easily when OFF the power,
then it pushes a lot while ON power.

Oversteer I can control with throttle modulation (and with zero trail-brake dialed into the ESC), but the push doesn't allow me to use full throttle until halfway down the straight...

[vwjuice]

I'd sat all the B3 since AE SUCKS and buy a good quality buggy like a Traxxas Bandit.



I would try adding a little weight first. Just too see if that helps.

You can also try different tires front and rear. On my T4 I used too run whatever the grippiest tire was on the front and I would run something like a holes got that would have great forward bite, but not as aggressive side bite. That helped a lot on that truck.

[Charlie don't surf]

Where in the corner are you lacking on-power steering, entry or exit?

Lacking on entry is usually a instant weight transfer issue, because of damping/caster/tire. But that's only the norm, not the only item.

If you aren't transferring (and keeping) enough weight on the front end during initial turn-in(damping), the front end will rebound somewhere in the corner, changing the weight and decreasing the effective cornering. Too little (caster) keeps the tire too flat in the corner to be effective @ speed when the top of the tire tips out from lateral weight transition and imbalances the front to rear. Wrong tire or compound of course is what it is-
On a side note, your truck/car should roll through the corner (off power) at the rate of speed you expect it too, if you add power before that point, you shift the weight and alter the corner-

Lacking on exit is usually ride height/caster/front toe issue, But again- there are other factors that can make a big difference.

When accelerating out of a corner the front end unloads and goes "static" where no spring or oil forces are acting upon chassis weight (theoretically) so if you have too much (ride height) in the front you can lose any effective contact weight on the front end. Decreasing the ride height and "locking down" the front end reduces this. (Caster) too much caster jacks the front wheel beyond the effective scrub point. (Toe) in decreases the drag arc of the inside tire, and increases the turn radius. Sometimes adding 1-2* toe out makes the corners come alive-

On the T3 (as I recall) you can move the on-center king-pin up and down via shims between it and the caster block, this helps the truck have more aggressive steering characteristics, as the on-center pin really pushed the top of the tires out on the truck. 25* caster is also prob your best bet, 30's should be aggressive in, and dull on exit. The T3 also had a very laid down front shock option, far outside lower- inside upper, if you try this you have to raise the rear oil weight and decrease the front to balance it out. Overall, without knowing the track-tires-conditions-driving style etc (sounds like you have a pretty good handle on all that) I would bet it is a front or rear ride height issue-

Now...back to Calculus

[Charlie don't surf]

.....oversteer to understeer? Ride height/droop- too much up-travel in the rear and front.

[dldiaz]

.....oversteer to understeer? Ride height/droop- too much up-travel in the rear and front.

Thanks for the info!

The problem is definitely on corner exit, I get through the apex fine, then it just pushes and pushes to the outside as I accelerate.
It is not because the truck wheelies, it is not an overpowered model at all.

So, the more laid down front shock position might help "lock down" the front end, as you explained... I think I will try that first.

Perhaps a bit of toe-out as my second step.

[dldiaz]

.....oversteer to understeer? Ride height/droop- too much up-travel in the rear and front.

Hey, could you explain:
""too much up-travel in the rear and front"" ?

I don't quite understand that.
Thanks!

[Charlie don't surf]

Well, the laid-down position is more for entry overall. I would reduce the droop (internal spacer install) and add a little toe-out, you will give up some stability in the straights with toe-out though-

[Charlie don't surf]

.....oversteer to understeer? Ride height/droop- too much up-travel in the rear and front.

Hey, could you explain:
""too much up-travel in the rear and front"" ?

I don't quite understand that.
Thanks!

If the front end rises too much, it loads the rear end with weight- not enough front end weight= lack of steering. By reducing the droop (shock extension) you "hold" the front end down, keeping weight on the front during acceleration

[dldiaz]

Okay. I have some good options to try.

[askbob]

Good points to note.