Having more rear bias, how do you adjust for the lost in front traction? As in, steering.
Sorry for not having enough time to read from the beginning, so far only managed a few pages. Have you arrived at a baseline ratio of front to rear bias for rear and mid configurations? :nod:

Shifting weight rearwards increases steering not decreases all things being equal. The reason this seems counter and why everyone gets it backwards is that if all you do is move weight but don't retune, you have also effectively changed the roll stiffness at each end.

The first sentence admittedly came as a surprise, but thank you for reminding me how this thread is different. Keep falling back to the old way of thinking. :sweat:

Let's rephrase that,
What would u recommend to do when we move weight bias rearward?

If my understanding is close, should it be to lower the front RC, increase front camber gain and lighten front shocks?
And it is not impossible for a 2wd to have good steering even with a 32%/68% front to back bias?

Tried it but doesn't work
 

Hi please don't take this the wrong way. I was going to use this method this season with a test rig but I'm stumped at stage 1.I drive a B44.1 and I tried to do the spring resonance testing on the bench and it doesn't work. On matter which springs I use on the rear end it settles down straight away. And no matter which springs I use on the front it remains very lively. It seems that spring resonance is not going to happen on a B44.1.

Try something a little different. With the oil out of the shocks push down on the front end with one hand and the back end with the other hand until the chassis is hitting the work bench front and rear. Release both at the same time and watch just the rate at which the front and rear rise. You can even video it and slow it down to get a really good idea. What you are looking for is the rate that the chassis moves up, nothing else. The end with more mass is going to oscillate longer. That's not what we are trying to match. We are trying to get the initial wheel rate the same from the springs reacting to the chassis weight. I'm not real familiar with the B44 but if you have the right springs you will be able to get this done.

So I have tried this, but are we looking for the initial rise to be the same speed. So shouldn't that first initial rise rise with a level chassis.

You must have a very soft spring in the back. Remember to take all of the oil out of all of the shocks before starting. Set the shock collars so that the car at rest sits arms level. This is done for easy reference. If the drop test isn't obvious then hold the car flat to the table where the chassis is flat against it front to back. Release and watch the rate each end rises. If one end goes up faster than the other, it isn't balanced. No car is immune to this technique. If it has springs then this will work.

I would make one change at a time, ergo just move the weight.

Weight is the last thing you should be messing with. I'm not saying you'd never want to mess with it. Just last.

Think so? I used to move the battery on my oval car all the time. If it needed to cut harder into the corner, I'd move the battery further back. It would hurt steady state steering and smoothness (because it forced more weight transfer) but it worked and it was easy to do..

I have to admit, I'm not a big fan of moving the battery. Its a coarse adjustment and if you subscribe to the theories we've discussed in this thread it will throw off the undamped spring balance front to rear. I could very well be wrong about this but for an oval car on a smooth track you were probably able to get away with this a bit more because the chassis wouldn't have been subjected to rapid positional changes (jumps, bumps, wounded marshalls, etc.). From what I have seen, it does work on off road cars too but you can start to unsettle the car really easily with porpoising and such. Now, I'm not a great tuner by any means so take this with a grain of salt...

Did I say that moving weight has no effect? I don't remember saying that anywhere.

bds: If you move weight and the car becomes unsettled it's because you've thrown your suspension balance off. It needs to be rebalanced. A balanced car doesn't porpoise.

I have to agree with everything you have written but this part, being that you mention real cars here. From my experience with a '70 chevelle and an '87 trans am, just a tire change alone made a dramatic increase in handling before changing out the stock springs and shocks. Most r/c racers will attest that tires are 90% of your setup.

I believe he is saying that you should start with suspension first so that your car is properly balanced. It's basically like making sure your car is setup properly before going out onto the track.

Yeah you're probably right.