well, after consuming the first 17-18 pages of this thread..I gave the spring frequency and next step around shock fluid tuning a go. (just into this hobby 6weeks or so)

B5 rear w 17.5 originally had white rear and green front springs. using slomotion ( benefit of getting into this 3 years after this thread started) on the iPhone i was able to confirm I higher frequency in the front and reset to middle top positions and end up adjusting frequency to match the rear landing on black front springs. beautiful.

it's a reedy 17.5, peak 90c 4000mah battery spectrum servo and futaba or 304 sb receiver ,viper vtx10 black setup.

cheating a little I didn't start w 20 weight oil, and w some of the advances in the b5 setup I left the stock setup 1.6 Pistons in the front and 1.7 Pistons in the rear.
I landed on 32.5 rear, 35 front losi shock oil after two other combinations. ran the track between and felt/looked like the right mix and pack. and car felt more planted and stable to the track than ever.

onto RC and the next steps in the process.. thanks to the contributors so far!

Think I found a better setup now.

Car is a Slash 4x4 LCG 1/8 buggy conversion for highspeed on-road usage.
Total car weight 4.3Kg / 9.5lbs
Front axle weight: 1.8kg
Rear axle weight: 2.4kg


Here is the new setup:
Front: Associated blue 83gf/mm, shocks in outer holes
Rear: Kyosho green 66gf/mm, shocks in outer holes

+ YouTube Video

Here is the first try with stock Apache springs:
Front: HPI white 82gf/mm, shocks in outer holes
Rear: HPI white 82gf/mm, shocks in 3rd hole from outer

+ YouTube Video

I will take a stab at it. I think the second video is a tad bit closer to being rising at the same rate. First one is very close. Any others??? Unfortunately i won't be trying this method until I can get a way to record in slow motion. I tried! I just can't notice anything without it.

I must have missed several pages of video for shock tuning...

This might be useful for dialing in a new car before its maiden voyage, but keep in mind having the same rise rates on a stationary table isn't always ideal on the track.
Where this would work(maybe what this is about and I missed it) is duplicating something that works on the track for you, on a different car.

Feel on the track, flight over jumps, things like that...número uno.

There are so many compromises.

What is the goal of this process?

I agree with your points. To answer you question though, it gives a known and measured reference point. I personally test various sets of springs so that I know which groups are balanced. That way if I need to stiffen up the entire car, I know which group will provide similar balance to what I had (which may be a purposefully unbalanced setup). Then I can determine which logical set to change when working on a setup.

That makes sense, a great tuning and testing tool to ADD to your arsenal, not a replacement.
...
I would use scales to see how much pressure it requires to bottom the car out at each end, or wheel, as well.
The video would mostly show the oil(damping) to spring relationship.

This combination would give you pressure(lbs/kg's) reference(scales), as well as damping(video) for given pressure.

Keeping in mind of course that wheel scrub has to be left unchanged for each testing session. Since it greatly effects testing without the wheels rolling.

Read the first couple pages of this thread to understand what he is doing.

He is attempting to match his spring rebound rates (using the different mounting locations).

Then he will work out oil and pistons once the car is similar in rebound rate front and rear. (using the springs and shocks to tune for bumps and jumps...just jumps and bumps...lol)

Then....he will make the car turn as he wants by adjusting the camber links, ride heights, roll centers and other chassis adjustments.

My understanding is that once you have worked out all the possible spring - shock mounting location combinations that are "balanced" you write these down.

If you are in a situation where you need the shock to be in on the shock tower and out on the a-arm, then you would choose a matching pair of springs where they are balanced (per your testing) in these mounting locations.


****there is a lot of theory in this process and none of it is mine. I am simply regurgitating what I've read over the last couple days...****

You mean the 2nd try video is better? I am not sure if I messed up the test because the right height in the rear is a little higher which causes the rear to look like it's not rising at the same speed?

This just seems like a lot of work I feel dorky enough playing with RC cars but I'm not about to record my car in slow motion to see how it rebounds

Yes 2nd video. Not sure if having one end higher than the other would have much effect from a completely collapsed start. But I am not the one to answer that question by a long shot. I wish I had a means to record my rebound in slow mo. Looks like fun and tuning is fun.

Some of us like to build, take apart and build again, some of us like to just drive, some of us like to do both.

I'm just kidding I like to build more than drive I think...or maybe 75/25. Sometimes I think the only reason I go to the track is so I can take it apart when I get home to clean it lol

Roger that! Not to hijack the thread, but I entered my first race in over 22 years last night. Had something to work on between every round. ESC came loose, bent front camber rod, peeled the velcro off the chassis so body would not stay on in main. BUT, you could not wipe that grin off my face for nothing. Need to learn how guide car again before I get to worried about setup. Ron Roy, an ex-pro said he thought the car felt great, I personally would not know.

I've made my own B4.2 mid motor conversion and so I've had to get better at setups, as there are no setup sheets. I've used the camber link tuning ideas to great effect. I can't say enough good things about them!

I've always put off matching the springs with no oil because it would take a long time (an hour?). Racing ended a bit early today, so I matched them. I ended up softening the front by two increments (green to brown). I can't believe how much better it is! It didn't oversteer like I thought it would after softening up the front so much. I'm a believer!

I've used this method a couple times and what I've learned is that its too difficult to drop the car and see how the front/rear rebounds. I found its just easier to set it on the ground, compress the suspension all the way and then let go. Tried it with the stock rc8.2e spring setup and found it to be pretty balanced as is.