Fordguru, I thought the same thing about high roll centers on a low grip track that I used to run on with my SC10, but increasing grip by running a high roll center contradicts most of hte info out there. Like you mentioned, I think Fred alluded to it somewhere near the beginning of this thread in stating something like both setups will slide on low grip, but the high roll center will provide more grip. I had actually made a recessed u-brace for the rear for that track to get the roll center as high as I possibly could. That track closed, and last summer I ran on a higher grip (likely considered medium-high, I think), and kept gravitating towards the high roll center with bad results (twitchiness and snap oversteer on corner exit).

Personally, I don't think low roll centers used in high grip conditions only offer an illusion of better cornering power. The weight transfer to the outside tires (once the chassis stops rolling.....key point) can't be overlooked, as it does increase overall traction I believe. The difference between low grip and high or even medium grip surfaces, though, is that on the low grip surface you can't even generate enough g-force to get the chassis to lean and transfer weight.

My two cents. Comments????

Can't offer anything on the center diff bit, as I don't run 4wd.

Fred I was hoping you could give us all a Flow Chart of how you tune your cars. IE.:
First Set spring rate balance
Second Set Spring Pack
Third Set Camber

I've got a question for you guys. I'm running a Hot Bodies D8 with Tekno V4 chassis on a very small, medium-high bite indoor track. The track is extremly small for an 8th scale, we run 1400kv motors on 4s or 2s and 4 pole sct motors.

The D8 is famous for being super stable, but I'm not getting enough rotation out of the rear end or maybe not enough bite on the front end. I tried lowering the inner rear camber link on the tower and it made it better. It still needs more rotation, I was thinking of going to a shorter link on the rear as well, thoughts on this?
Thanks

Pg 1,2,3.....98,99,100... And I've reached the end. Thanks everyone for the info. I think I'm going to name my first born after Fred. I thought I had a pretty good understanding of off-road rc but wow did I have a few things backward. I have an idea on "pack" or dampening. If u want a balanced car with spring rates wouldn't u want equal balance in dampening? To achieve proper dampening balance shouldn't our cars compress at a similar rate?

Once u have spring balance can't u take them out of the equation. Use the shock locations as constants and adjust oil & piston size to once again get balance. U could use the same drop test. Take away the springs and in goes oil.

Now I would think that u would try to get the car to compress in the same way as we used for the springs. Nice and level and at the same rate front to rear. Thicker oil=stiffer, thinner oil=softer. A thinner oil would be better for rough tracks where the suspension is more active and thicker for smoother tracks.

U then would use piston size to affect the speed at which the shock compresses. Bigger hole faster, smaller hole slower.

Example is 30wt front & rear but the rear compresses or"bottoms out" sooner the the front. The front still bottoms out but a little slower. U could then add or increase hole size in the front to get the car to compress at the same speed front to rear.

Does this sound loci cal or am I totally off base?

Sodakota,

I think you're on base (for what that's worth). Once the springs/shock pistons are set, I think they should be out of the equation as far as damping goes. But keep in mind that the shock mounting position is very important to damping, too. Not only does it affect the leverage of the damping affect on the suspension arm (similar to its affect on the spring rate), but it also affects piston speed inside the shock, which also is a big factor in damping, just like oil viscosity and piston design are.

I agree with you, too, on getting the damping balanced, too, or at least knowing where you are with it, rather than just going by what somebody has told you works for them.

Go for a shorter rear upper link, side effect is increased traction on-power so you'll have to mess with higher or lower inner link position on tower to fine-tune.

Do you really want his name to be a four letter F word?

I never really got into dampening but I do balance it on mine too. I've got a couple of simple tests that I came up with to set things and the end results are a bit interesting. I just haven't had the time to write any of it up.

I guess if I had to comment it would be that I would think without the tradeoffs having equal tire pressure (higher RC) would be ideal on paper. With traction available maintaining maximium contact. But I now know and have felt the tradeoffs. I have already seen results from my new found understanding. I cant say enough about the value of this thread to me on clearing some things up better! Some smart folks here.

Trying to gain full understanding of Camber change now. I have converted to Ebuggy one of my MIP SCTE's with the Pro8. On the tower it has new Camber holes to play with more toward outside similiar to B4.2 rear tower holes.. I look forward to more understanding that should come in my next practice day or throw away day at the track.

after reading this thread ive been obsessed with my set up well more than usual i guess. i have 3 sets of springs that balance my car and now im working on the dampening aspect. here is my delema our local club races only 1 day a week. ive been working out the kinks on my set up during race nites since there is no practice days. between marshaling and working on set up i havent been able to really get full potential out of my kit. the track is indoor carpet with some big 10ft plus jumps to flat. last week i messed around with diffrent oil wt but am still a little lost.

my question is what would be the diffrence between a lighter oil with small holes vs a thicker oil with more/bigger holes? my gut tels my that u can acheive the same results with either. i know there are alot of smart dudes looking at this and would like to hear what u think.

That's a good question and an important one to know. Long story short, if both gave you the same wheel rate, the setup with the bigger holes with thicker oil would have less shock pack than the one with thinner oil and smaller holes. If you have a rough surface then you may favor the large hole/thicker oil scenario. If you have a smoother surface with large jumps, you may favor the thinner oil/smaller hole scenario.

Also the number of holes comes into play as well right? If the hole count is the same then what your saying is an easy thing to work out. But if there are say 10 holes at 1.1 size or 5 holes at 1.3 the 5 hole piston would have less total hole area and more pack? (11 vs 6.5)
The 5 while would have more resistance at higher shock speeds than the 10 hole?

That's where it can get a bit confusing. If you have two different pistons with a different number of holes, the one with more total hole area will have less pack. However lets say they have equal open area but a different amount of holes. The one with more holes will have more pack. I have a general rule, and it's really just personal preference. I use the same number of holes all around and only vary the hole size. If I'm running a 6 hole piston up front, you know I'm running a 6 hole in back too.

So for a quick comparison of some standard 12mm buggy pistons:

1.6x2 = 3.2 surface area (more pack)

1.4x3 = 4.2

1.3x4 = 5.2 (less pack)

heres a piston pack chart. The larger the number, the less pack it has