Hideeho
I tried using smaller holes in the front pistons & bigger holes in the rear. I'm driving a b4.1 w/ the new AE big bores. To set a base line I ran my usuall 1.6/1.6 w/ 30/27.5wt oil. For the test I tried 1.5 holes in front w/ 20wt & 1.7 holes rear w/ 30wt. It seems pretty well balanced & I didn't have capability at the track to use slomo video (I'll try it at home later). I really like my base line setup & made no other changes before starting to drive (I did reset height to 24mm front & 23mm rear plus camber to -1 all around).

In general the buggy felt the same. The upper limit of traction did not seem to change. There were 3 areas of the track where I did feel a diference.

First was the fast sweeper coming off the front straight. It is very rough & has been blown out & patched twice now (will probably happen a 3rd time before we get a new layout for Dec 1 state championship race). When I over cooked the corner or got to wide it was MUCH easier to correct.

The second is our 1st big double. It has a long, almost completely flat (5*-10*) down ramp. If you don't land it perfectly (nose slightly, but not too much, down) the rear end slaps. The big bores had all but eliminated the tail slap, but this config put it back to about where it was with the v2's.

Third is a hair pin right after the 2nd double. This corner leads to and odd long down slope jump to a table top. The table top is too far for a bitty buggy to hit (1/8 has tough time & most don't do it during races), so I take the hairpin as tight as possible. With the new setup it is very easy to rotate the buggy around the point & take off for the jump.

To summerize, the new setup gives the rear a slight amount more rear traction while still allowing rotation, but at the expense of landing 1 big jump with a bad down ramp. The trade off is, in my mind, a good one. I do plan to verify balance by slomo video & to try upping front & rear by 2.5wt. Hopefully the 2.5wt will be enough to slow down the tail slap, but still keep it balanced for easy slide recovery.

Great thread this has become!

I will start the tunning process tonite. This is what I'll do:

-Remove springs.

-Check chasis balance with 4 scales (one on each tire) to try to find a balance between L-R, and I also want to know what is my balance percentage as to front and rear. F-R balance only for reference purposes. This info might come in handy later on.

-Drain all oil fluids and reinstall shocks with only springs on them. I'll try to find a couple of spring rate combos that work. I just got all available spring sets for my TLR 22SCT (5 front + 7 rear + stock springs).

I guess this is all I can do at my place, with out going to the track on Thursday. When I'm there, I should just pick an oil wt and start "feeling" the truck around the track, watching for erratic behavior or plushness, I guess?

(I am hopping I can achieve spring rate balance from today till Thursday though!)

Here's something to think about in terms of big bores. I wanted to know how close the equivalent pack of the standard bore shocks were to the big bores. Basically I looked at the total piston hole area vs the bore area. Logic would dictate that maintaining this same ratio between bore sizes would result in the same equivalent pack since oil speed through the holes would be approximately the same.

AE standard bore shocks:
#3 pistons .84% hole area vs bore
#2 pistons 1.05% hole area vs bore
#1 pistons 1.18% hole area vs bore

AE big bore shocks:
1.5mm 1.16% hole area vs bore
1.6mm 1.31% hole area vs bore
1.7mm 1.49% hole area vs bore

Keep in mind that I can't account for the tolerances between piston and shock body or leakage in this area. Basically what we can gather from this is that the big bore shocks run far less total pack than the standard bore units. They will definitely feel different from the standard bore pieces for this reason alone. I'd love to see how different handling is between them with the same approximate levels of shock pack. Keep in mind the big bores may not require as much total pack as a smaller bore so don't think I am crying foul. Not at all. Just something else to play with!

Hideeho
In the instructions for the big bores AE not setting any preload. That is the way I set them. I used the same springs (I was using losi bb springs on my v2 shocks) & the same weight oil. I used #2 pistons in the v2's (the middle ones) & 1.6 (again middle ones) in my initial setup for the bb's. The pistons for the bb's are thicker than the v2's. The bb's had more of a damping effect on fast piston speeds (landing jumps) but felt like they have the same or less damping for slow speed (cornering). Iirc, when the CSI pistons 1st came out the guys @ CSI recommended 5-10wt less in agama's bb shocks (17mm vs 15-16mm for other brands) because there is more damping effect moving a larger volume of oil (at some point I'll go find that post & link it here). This seems to be what is happening with the AE bb shocks. this also leads to several ideas for pistons with the bb's. Namely, shaving the pistons to make them thinner (& using thicker oil), beveling the piston to get home made taper pistons, custom drilling some pistons to emulate the CSI pistons (1-2 larger holes & 1-2 smaller holes). Hopefully AE will come out with blank bb pistons & regular piston sets for sale separately soon.

P.s. I love having new things to tinker with!

Although, what you said would SEEM logical, this is actually not how fluid dynamics works. The relationship is not proportional relationship but rather exponential depending on hole diameters and piston height.

As I said it was a very general statement. I'm definitely not taking many things into account with it. It was really intended to get people thinking a bit more since these aren't going to be the same animal as standard bore shocks.

Ok, so apparently I just found balance in my spring rate frequencies on my 22SCT. I also checked weight distribution and found L-R are pretty much balanced. This what I got:

Front : 3.8 Blue (stock)
Rear: 2.9 Orange (22 buggy)

Weight distribution

Front: 400 gr LT; 393 gr RT
Rear: 628 gr LT; 632 gr RT

Next step I need to find a correct oil combo. So for these test, I guess I will start with the stock 27.5 all around.

I should look for both ends settling more or less at the same time right?

After a race on the weekend, I noticed my tire wear is a little uneven. What can people tell me about this tire, the left of the picture is the outside of the tire. The very inside of the tire shows almost no wear, so I'm thinking that my roll center is too low?

This is from a rear motor buggy racing on a high grip outdoor clay track that has quite an abrasive surface.

If its a real car then the tire pressure is too high and too much camber and may be too much tire spin. Correct me if I am wrong.

Quick update.
Dust off my 2wd buggy,rebuild rear shocks with 30wt shock,now it drives like I want.Great success!

Page #9, post #128.

I didn't read through the whole thing, but it's in there.

How much camber?Rear link positions?Tire compound and foam insert?

Rear camber is -1 degree. The tire is an M3 Holeshot with the foam cut down to the same width as the wheel.

My camber links are the same length as the wishbone and almost parallel, just slightly angled downwards on the inside, so it's a very low roll center.

The track was so grippy I had almost 100 rear traction. With my slipper almost locked, I could mash the throttle from a standstill and lift the front wheels.

It's the inside strip of high unworn pins that is intriguing me, I would have thought the wear would be more gradual rather than going from 0 pin height to 100% pin height in one row.

The car is a Cougar SVR btw.

Edit : Just to clarify, the small strip of high pins next to the bald section is on the inside of the tire (i.e. towards the car).

Hideeho
I believe the problem is the trimmed inserts. Because you have so much traction when you corner the carcass of the tire is sliding across the insert (are you glueing the insert to the wheel?). Now that the tire has slid to the inside the next time you corner the part of the tread at the edge if the insert effectively becomes the sidewall. You also have high camber gain causing the tire to have lots of negative camber while cornering exacerbating the problem by putting most of the cornering force onto the new sidewall.

I would recommend a full size insert or a molded closed cell insert (probably even better) & less camber gain. You may also want to redo the balance setup of your buggy with stiffer springs & oil before you adjust your camber gain.

Edit: I originally read it wrong & thought the worn part was on the outside of the tire. That would indicate almost the exact opposite problems.

This updated pic should clear it up...

With my long parallel links, I have almost no camber gain as the suspension compresses. I suspect I'm rolling too much and lifting the inside edges of the tires off the ground???