The more camber gain you get with suspension compression, the less total contact area you have when the back end squats down during acceleration. This of course is ignoring tire flex which may compensate for this to an extent. A longer rear link will have less camber gain while a shorter link will have more. Theoretically this would mean a shorter link would have less straight line rear grip during hard acceleration but in practice that may not actually be the case. Camber link length will be noticed most in corners.

i'm currently toying with the idea of using XB4 rear arms on my B4.1 (or what is left of it), the problem is: they have 2 mounting locations for the outer hinge pins and the car will be either much wider or much narrower than stock. (approx. 3-5mm per side) What effect will a change of the rear track width have?

my options would be:
B4.1 rm3: much wider/narrower
C4.1 mm4: a bit narrower
B4.1 mm3: much wider/narrower

I had always run my rear links as long as possible, and was always dealing with the the rear end being very loose, and prone to stepping out very easy.

During a recent practice session on a very loose track, I tried moving it to the inner hub position (as short as possible). I did notice a slight decrease in forward traction, but a huge increase in side bite. The rear end was totally locked down, and allowed me to roll through the turns faster, and get on the gas sooner at the exit. With my driving style, I don't swing the tail end around in turns. It's more of a "tail follows the nose" kind of thing.

Going to a shorter link was totally against the typical "long link = more traction" logic that I had always known, but I tried it again the next time I raced, and liked it much better on a thoroughly prepped track as well.

Unless I'm on a super high bite, blue groove track with no dust, I'm going to keep the short rear link. I like the way the car feels better than with the long rear link.

How are you getting those values?

Saw the same thing with my SC10 on a low traction track. Anything medium to high traction and I start having issues getting on the gas on corner exit, and seem yo do better with the long links(lower roll center).

That's because too many setup books and racers over simplify suspension settings. Less roll, more roll? LOLz. They never mention where and when.

Too often, something that takes away traction on entry, gives it back on exit.

So on my SC10, it's a lot like yours. Full short on the rear links makes it loose on entry (almost always a good thing), and increases side bite and grip under power on exit.

I have a 3 ring binder that I take to the track with not only printed setups but all the oil piston gear etc etc charts I find on the net. Used for reference, remembering all those numbers and details is difficult. Sometimes it's also nice to read something that confirms your thinking. However fwiw I work on my car less than anyone I see. At the end of a run when back in the pits I usually sit and look at my car for a while. Pull out the book, sit and think some more. Maybe a little adjustment and clean the tires. Think, tweak, run again.
I can make a cool bomb from memory but I would need a binder to be a rocket scientist.

I had my E3.0 on the track for the 3rd time yesterday, after the first time with stock setup I had bad wheel bounce on small sharp bumps. So I balanced my suspension per this thread, worked out the oil wt. I like the way the shocks are handling bumps now, jumps well also. My experience out this time was the back end sliding out easily after landing and turning immediately for a corner. Also understeer on corner exit, turn in seemed fine. Hard on brakes into corner rear was planted. So scratching my head thinking of suspension geometry, what to try. I was at upper links same hight and length front and rear. Same sway bars, lightest also. Hard to change driving style when turn is just after a landing, gotta turn or hit the pipe. My shocks are a lower frequency to deal with bumps, so I thought I need more roll stiffness. Also, rear wheels wearing more on outside between middle and edge. So too much roll, right? Also causing rear washing out? I shortened links in the rear, hard to tell any difference. Shortened front to match, felt like I could drive the buggy faster and rear wasn't as loose. On power steering improved, but really helped to quick tap brakes half way through corner then more than enough on power steering. Any suggestions? Could really use the help. Also rear tire wear, harder on bead area like wanting to get torn off the wheel. No matter setup always harder on rear bead and sidewalls than front. Front wear is about even across, after shortening front link noticeable more inner tire wear.

Try removing the rear sway bar but raising the rear roll center with the camber links.

Fred, honestly removing the rear sway bar was going to be my next move but track was closing. That would give me a lot of extra weight transfer, do you think that would make my rear tire wear worse? I make it to the track only once a month at least, so making moves in the right direction helps. I understand it's all a learning curve. I feel setup is like a different language and what does what are the words, how to know what to apply it to the buggy is speaking fluently. I know the word I just can't speak it yet. If that makes any sense! Thank you for your help.

If your tires are wearing more on the outside than the inside, you're roll center is very low. Raising the roll center either by lowering the inside link or shortening the link will cause that wear to move inwards. I tune my roll centers based on tire wear.

A sway bar is a device that does increase roll stiffness but it never adds traction. It only takes it away. If my tire wear is where I want it but my steering isn't, I'll use a sway bar to even it out by adding a sway bar at the end that doesn't have a problem. In other words if the car is oversteering I'll add a bar in back.

I thought I read that you said to use camber links to get tire wear even. So that was my first move to shorten the links. They're as short as they can get, I'll try dropping it next time out. Do you think the outside tire wear and rear end sliding out are the same issue? Rear roll stiffness too loose. Too stiff and you get inside tire wear, due to lack of body roll? Also, wouldn't adding a rear sway bar give more steering?

Are you running any negative camber?

-2 all corners

Which car are you running?