Try tightening the diff.

One thing I didn't see you mention. Do you have too much steering off power going into the corner or too much on power coming out of it?

Both on and off power. Probably more so off power. Once the back end starts swinging, it's hard to get on the power anyways, so that could be affecting the on power over-steer. But even if I slow right down going into a corner so the back end doesn't break loose, it's not like I'll get an on-power push from that point on.

Are you running the right tyres for your track?

Also where abouts is your rear shocks mounted on the arm?
I found inside hole give more steering and slightly less stability.
Outside hole removes steering and adds a little stability.

Also, how much toe are you runing?
Front and rear?

Never asked about droop or ride height either. It's strange that no matter what is done that it has too much steering. It should definitely be able to be tuned out.

Definitely not a tire issue. I've been racing at that track the past 2 years and know what works.
I've found the exact opposite with the shock mount on the arm. Inside gave me more rear grip and less steering. Outside gave less rear grip and more steering. But I was trying not to mess with that since the springs were balanced with a specific hole location.
Rear has 4 degree toe in, which is the max I can get. Front, about 1-1.5 toe in.

My ride height is rear 29mm, front 30mm, which is pretty much the stock setup. Droop is almost stock as well. I did add a bit more droop up front to help with forward traction.
The only thing I've found that really makes a difference in calming the front end have been stiff front springs, and really low grip front tires.

My SC10 was giving me fits with oversteer mostly doing quick maneuvers like a chicane & trying to set up for a jump immediately after a turn. What was happening was the truck wanted to continue to roll thus over-steering coming out. Going in and letting off throttle was okay but braking would put it over the edge and it would lose grip and slide.

Backing off on the slipper helped some. What really helped was putting the front & rear camber links in the same location at the wheel. For my truck it was middle on front & middle on rear. Felt much more confident going in & coming out of turns. Looked at the lap times and they were lower by at least one second.

It took me a long time to figure it out. At first I thought having a long link & low roll center was the answer to my prayers. But this only made the truck worse. It would just roll more and magnified the problem. Maybe it would work on a larger track. The one I am running on is about 60x40. The longest straight is about 30'-40'.

Adding more weight to the rear caused me to oversteer more as well. Moving my battery all the way forward works best for me. That was discovered in my process of trying to find my 'oversteer' problem.

Everything is a tradeoff. If you can't get the steering that you want with a balanced spring setup then go ahead and unbalance it a bit. Even if it doesn't take the bumps as well if you are faster that way, use it. Something is still a bit weird though.

Hey fred, thanks for this great thread. I know it has been discussed before, but could you please give a quick explanation of how moving the upper link either up or down or making it longer or shorter affects the car? I want to make sure what i have written down is spot on.

I've read through every page, and nearly every post in this thread. Amazing information Fred and we all owe you a debt of gratitude for that. Also to the other contributors who have helped out, thanks to you all.

I just started this process on my RB5 last night. Spent about 4 or 5 hours trying different spring combo's and figuring out the best way to actually "see" the balancing in action. I found that dropping it was too difficult. Not only can I not see when it's coming back up, but the rear bounces around too much. I then tried to hold down both the front and back and let go at the same time. While this worked ok, I found it to be fairly inconsistent. Finally I tried the center of gravity method. To me, this works the best.

What I did was put a hard case 7.4v lipo sideways on my work bench. I then balanced the car on it until it would rest on it without tipping to the front or rear. I then used the center point of that battery and marked it on the top of my battery strap. Once I had that figured I pushed down on that point with a nut driver. I watched how evenly the chassis would move down, and then after getting it all the way flat on the bench, watched how each side raised (speed wise). To me it was the easiest, most re-creatable, most consistent way of doing this.

To verify that this worked I simply purposely unbalanced the car. You'll notice as you push down on that center of gravity point, if your front is too stiff it will end up hitting the bench after the back has already touched. Likewise if your rear is too stiff, it will do the same.

To me it's a great method of testing this. You can literally push down on the center of gravity point VERY slowly and watch the front/rear touch.

Is this a proper way to do this, or is there something wrong with my method? I tested it and it seems to hold very true. Plus it's a lot easier than trying to judge the "speed" of the lift in the springs by just eyeballing it.

I did preliminary testing just as you describe, however, I will attemt to explain why it got me into the ballpark and not "fine tuned"

To my thinking, the only problem is the difference in "progressiveness" of the front or rear.

Examples:

1) One end of the vehicle has the shocks upright, and another end they are laid over.
2) If the front spring is shorter than the rear.
3) One end (usually the rear) is greatly preloaded vs. the other.
4) One end has a specially wound type of spring that affects progressiveness vs. the other end.

These all would seem to me to have potential to throw off the "bottoming out" test.

The "mid range" of shock stroke used on 95% of the track, where the suspension should not be (or even close to) bottoming out on, is the part of the track to tune and balance for.

Again, these are just my musings. Take them with a grain of salt.

It's good that you brought that up. I try to find a setup that allows the orientation of the springs to be as close as possible front and rear. If the backs are laid over, I want the fronts laid over as close to the same as possible. It's a personal preference but with the intent being balance it makes sense to have the same amount of leverage at the same amount of travel.

So my method of doing the "push down" on the center of gravity should be ok right?

Just wanted to double check before I go too far. To me the science and the tests I did seem evidence enough that it's a good gauge to determine my front/rear balance. I ended up with quite stiffer springs on the rear, same ones on the front, so I'll see how it goes tomorrow during racing. Still need to work on my shock oils though. Going to wait until I hit the track for that though.

Oh and one thing I did notice is that my pre-load (spring spacing) is almost dead even from front to rear. Not sure if that's luck or because of the balancing I did, but just an observation I had.

Use whatever method works for you.

That's how I did my SC10, and my kid's, too. I ended up using stiffer springs in the back to make it balanced, as well. It's made the back end a bit looser both off throttle and on, but I've got some more things to try tomorrow to hopefully get that improved. With my truck, I've ended up with much more preload in the back then the front to get the ride height I want. I've also got the rear shocks more upright than the fronts, and would like to get them more laid down, as well. I only need the time to go through the balancing process again. Dang elusive time, anyways...