Kind of.

1lb sitting on a soft setup is still the same as 1lb sitting on a hard setup. Either way, any given tire will have the same contact patch with either setup.

What springs/shocks change is the amount of weight that is transferred to that tire when the rig is in motion. A very stiff setup will resist a change in weight bias, and a very soft setup will more freely allow a change in weight bias. That change in weight bias changes the shape and size of the contact patches of the tires at each corner. If you allow the weight to shift to the outside rear while cornering, that tire will provide more grip than it normally would, just as allowing the weight to shift away from the outside front, that tire will provide less grip than it normally would.

If adding weight to the front improves cornering, that means the front needs to see less weight moving away from it. Adding weight is the easiest option, and unless it is a great deal of weight that is needed, you can re-tune the suspension and have similar results.

Not always. Sometimes you want more weight. Remember that all of this is to optimize traction where it is needed. A perfect weight balance at all times is not ideal. Sometimes having more weight at one end or side or corner is.

not really what i meant. When you have a heavier car you also need heavier shock oil don't you? Now imagine putting a shock of a 1/5th scale on a 1/8th buggy, it will be way too hard for such a light car, so adding weight will make the shock work better and mantain contact beetween the wheels and the surface.

i'm usually not a big friend of weight transfer mm3 rules!

Most of the time i run a little bit more weight at the rear 48/52 or something in that direction.

Not always. It depends on what you are trying to achieve. Everything is relative.

A smooth, high grip track will favor a stiff setup with less weight transfer. A rough, low grip track will favor a soft setup with more weight transfer.

i'm running on a relatively small bumpy high grip track

Then you need to find a good compromise between something soft enough to absorb the bumps yet hard enough to not transfer weight to a degree that you will traction roll in the corners. However, you can accomplish that with more than shocks/springs.

I think FS said it early on in the thread (heavily paraphrasing here)...if you are not sure which way to go, pick one and take it to the extreme and see what the effects are. Personally I learn a lot more by doing something wrong than I do by doing something right.

Don't overthink things guys.

Over the weekend I did my testing as promised however I'm not going to include those results in this post, instead I'm going to provide more factual post on some better tests I created. From what we can see from actual rc car designers is that less weight increases the possibility for higher cornering speed (notice the word possibility).

Now the test I used was similar to the test the myth busters used when looking at how slippery a banana peel was. Here a picture of my actual setup
As you can see as the hight of one end is increased, the side loading of the tires are increased. So for my weights I used one lipo saddle pack and two nimh 6 cell stick packs. So without going further here are my results (I still want to test it a few more time to verify it but here are the initial results)

Test 1(no weight)
Reached a hight of 17.5cm

Test 2(1s lipo)
Reached a hight of 17.4cm

Test 3(2s lipo, full saddle pack)
Reached a hight of 17.1cm

Test 4(6 cell nimh)
Reached a hight of 16.9

Test 5(12 cell nimh)
Reached a hight of 16.7

Now these results are as I predicted how ever I stumbled across something I hadn't really out much though into before, for the lighter car when broke traction it increased the rate at which it fell at a quicker speed than a heavier car, so for an example let's use the one from the team associated engineer. If we have a string with a mass at the end and we start swinging the mass in a circle the lighter mass can reach a higher speed before it breaks right? Well once it breaks free from the string it's also leaving the string at a faster rate than the heavier mass too and what that equates too is that a lighter car can corner faster but when it looses grip it's more violent and harder to recover from and a heavier car being the exact opposite. Now what we are experiencing with increased traction with the added weight has a lot to do with this. Since we are driving on dirt and there are many inconsistencies, we are experiencing is the tire constantly being loaded and unloaded, well what I'm trying to get at and I'm not sure how to lead into this is that when we are driving at the edge of our traction limit and we hit a small bump which loads the tire and decreases tire effectiveness we loose traction and we effectively have 0 lbs of traction force, and a heavier car is less effected by it to a certain point. We can also see that as weight was added the decrease in traction wasn't radical, so when we add weight to the car we are trading a little traction for more stability/drivability making it easier for us to drive at the edge of our limits more of the time. Clear as mud?

Nice work!

I figured this would be better than using antisquat to test my theory, plus now the results are quantified instead of just by "the seat of your pants" kinda thing.

When traction broke on the lighter car you mentioned it fell at a faster rate than the heavier car.... do you think the angle of the ramp would also have an influence on the rate the objects fell? You would have to eliminate this variable before that observation can be quantified.

That's the exact reason why it fell faster, now we cannot do this test without getting the same results regardless of the angle.
Think of the increased angle as an increase in cornering speed, if you are cornering faster when the car does loose traction it will act more violently and act the same was as the test shown with the increased angle.

Agreed.

That test isn't valid without that battery secured in place. Standing it on end like that changed the Cg and therefore the result.

Doh.

I don't believe that to be relevant because each car will have a different COG will be affected in every setup down to the suspension height and the roll resistance, and get to different heights but they will all follow the fact that as weight increases tire efficiency is decreased. If you wanted the most accurate test possible you would have to weight the tire directly with it being perfectly 90* to the surface it's being tested on. And I don't have the time to go that far into it and I don't see it as productive. If you wanted to nit pick you could say its invalid because I have two different sets of tires front and rear. I'll also add that I was consistent in testing and all packs were added vertically