hey Fred I lost the place where you mentioned u like to start at a shock location that ends up perpendicular to the arm at full travel. Then u match angles front and rear. I did that on my xb9 and the best angle is top outside hole on tower with both bottom shocks on outside hole. I looked at my b6 and it’s similar it seems the furthest tower hole out on most models gives you the closest perpendicular angle. Wouldn’t that leave little tuning option if u had to move the hole out one more to achieve balance? In my case would t be better to start with stock locations and work from there?

Sorry meant to say full compression

Also to match shock angles front and rear after finding the perpendicular angle make u change from that location?

when u say equal up top front to rear say I’m third hole out on front tower do third hole out on rear regardless of angle? And bro if u knew how interesting this thread has been for me I’ve spent hours reading trying to get it all down, but I’m quickly learning actual application is where the learning takes place. Thank u for helping me out brother

no what your saying makes too much sense, I don’t know how you could read it and think differently??? Lol. As far as Ackerman, castor angle and bump steer will these have as noticeable effect on steering as camber links? Also, camber gain really confuses me...on fwd does more front camber equal more steering? It makes sense in my head becaus the tire leans over flat and would have a better contact patch, but I’ve read on some tuning guides in the rear more negative camber frees up the rear... that doesn’t really click in my head. I would think as the rear seats left to right the outside tire can have more contact patch... so does transferring weight to the outside tire produce more grip? More roll more grip? Or would trying to keep the load equal from left to right produce more grip? What do you look for when starting to tune roll centers to know whether to address front or rear

What has a "noticeable" effect is not necessarily a huge effect. Lots of people look at all the adjustments and at tuning guides and nothing states what is going to be more noticeable and less noticeable, so they expect every adjustment to be something that is obvious. Tires and shocks are the biggest things to get right. Get those wrong and there's nothing else you can adjust that will fix it. Everything else is essentially fine tuning.

Front wheel drive is interesting as they inherently understeer. Not so much due to weight distribution, although it's there, but rather tire loading. A tire can only develop so much traction. I'm going to greatly simplify here so please don't nit pick but let's say that if the tire only had to generate grip for turning that it could use 100% of it's ability for that. Now let's say that the same tire also needs to put power down to generate forward grip. If 40% of it's traction is being used to generate forward movement, that only leaves 60% of it's remaining grip for cornering. That's less and it understeers. Again, that's greatly simplifying things. The point is to maximize contact patch but that doesn't necessarily mean that we want the tire completely flat with the surface.If that's all that mattered we'd just run swing axles. You start getting into suspension jacking effects. We want "some" amount of camber correction. Things get complicated very quickly. On a front wheel drive car, one tuning solution is to make the rear end roll stiffness very high. High to the point that the inside rear wheel lifts in the corner. This helps the rear end swing around and transfers some weight to the front opposite corner in the terms of vertical load, hopefully increasing it's grip level. Whatever you do to the load at one corner of the car affects the diagonal corner to it in terms of weight.

Getting away from fwd again, if we run lots of camber gain, as the suspension compresses we roll the tires inwards reducing their contact patch and total grip potential. Then we try to dial in more amounts of anti-squat to help counter this. That then reduces on power steering ability and now we go back to sway bars to help balance things out. You get the idea. One change affects lots of other things. When I start tuning, I start with low roll centers with little to no camber gain during suspension compression. I start with little to no rear toe and little to no antisquat. I always start at a point of neutrality and then tune from there. A low roll center is easiest to drive. It's the most forgiving. It doesn't necessarily mean it's the fastest setup though. Start with the tires. A poor tire choice will be a poor tire choice regardless of whether the car is tuned perfectly or not. Get this right. If you are real serious try not only different tread patterns but different inserts, hardnesses, and even staggering inserts front to rear. Next you go to the shocks and through the procedure there. Everything else after that is fine tuning. I like full geometric ackerman on tighter, higher grip tracks, and little to no ackerman on high speed tracks or loose dirt. It's a personal preference. I dial in antisquat based on how the car accelerates. If I have trouble spinning the tires during acceleration such as on low grip tracks, I'll run more antisquat. On high grip tracks where this isn't a problem, I'll run less. If your car can pull wheelies, you definitely have too much dialed in. This is a fine tuning step. Rear toe is the same way. I start with none. If coming out of a corner under power the rear end gets a little squirrly and unstable and fishtails a bit, I'll add some back in. Recognize that a higher rear roll center may also have the same unstabilizing effect so you might find that if you need a higher rear roll center that you'd also need more rear toe to help it. That's not a rule. Just something to be aware of.

In regards to tuning camber links, start with a low roll center. Get the tires and shocks dialed in. Drive it and see how it corners. If the car wants to oversteer going into a corner, you can try raising the front roll center a bit. Experiment with shortening it or just raising the outside/lowering the inside a bit. Where it gets a bit complicated is if you have turn in oversteer but on power corner exit understeer. Rather than playing with the camber link, you could try reducing the steering block caster angle. Caster leans the front tires over in a corner, effectively giving camber gain. The rears don't have this luxury. On top of that we have the front kick, which is especially pronounced on 2wd buggies. Keep in mind that most of what I say is in reference to 2wd buggies as that's what I mostly drive. A higher front end kick will transfer more weight off of the front during acceleration and it's especially noticeable in coners. People spend tons of time trying different camber link and swaybar settings trying to compensate for what the caster angle and front kick are doing that the rear end doesn't have the benefit (or curse) of. Then you end up with a car that has dramatically different roll centers at each end. How else do people fix these things? They run overly damped suspensions, extremely low ride heights, to the point where the roll center location is terrible, and severely limit droop. Sound familiar? This is why I try to use a process for tuning and arriving at a solution. I don't know how a setup on a setup sheet was arived at. It doesn't tell me what was tried that justified that solution and without that understanding I don't know what to do to fix something if it doesn't work right. You can't learn anything that way.

I'll leave this with a real world example, which some are going to claim is irrelevant to the rc world, but whatever. On my older RX-7's that had MacPhereson front struts, the camber gain is very little and at suspension droop you get positive camber. On cars like that, they typically handle the best with very heavy swaybars so that the car stays essentially flat in corners to maximize contact area. A downside is that they are disadvantaged on rougher courses since a swaybar is a link that connects each side of a formerly independent suspension making it less independent the thicker the bar gets. On the later RX-7's and other cars that had double wishbone suspensions, they had more inherent camber gain and more favorable roll centers through suspension travel so they could use a comparitively lighter sway bar in effect. They generate more grip and especially more when the track gets rougher. There are other advantages and disadvantages to each system that are not relevant to this discussion but I just thought the camber gain and sway bar setup differences might give you something to think about.

You will read a lot about inner and outer mounting holes on arms providing different handling characteristics. I’ve tried both and can tell the difference. I wonder though is it the position on the arm the makes the change in handling or the wheel rate? For instance if you had an equal wheel rate with accompanying springs that made for the same wheel rate with a completely laid down shock on the outer hole of the arm vs completely stood up shock on the inside arm hole would the car handle differently ? Based solely off location of the shock mounting positions? I can’t seem to believe that the shock “feels” the bumps differently the arm its a stiff peice of plastic and can a car actually tell the difference between lateral and vertical loads I don’t think it can but let me know. I hate reading tuning stuff it all contradicts. Like I saw this one article where they were quoting mark pavidis talking about 1/8 four wheel drive buggy and he said he runs the lowest hole on the tower camber link because it allows the car to roll more resulting in more aggressive steering, even a Losi tuning guide said that...I don’t really know shit but doesn’t it make it roll less? The top of the tire leans outward pulling on the angled link which in turn lifts that side of the vehicle up actually keeping it flatter...am I right on that? Because they said they longer link would keep it flatter? Smh haha