WWPF - Fastlane Raceway

My msb1 arrived about a week ago, and after some time building, i got out for two practice days, and while it was for sure an adjustment to try to tune a new 2wd after running an ae for a while, and i wont lie, it took a while for me to find something i liked, and i wasn't even locked in until today, where I did my first race with it, and ive gotta say, this is probably the most surprised I've ever been with a 2wd buggy. I was close with several FAST AE drivers, people who travel to races around the midwest, and hold their own in the modified class, so I was for sure not "out to lunch" with my b7 setup, and im by far more impressed with how few tweaks the kit needed out of box to truly keep up. Below i have attached a setup sheet for anyone looking to get one, and might need a "jumpstart" on setup. I run on clay, in general, very high bite, even for clay, however this weekend the track was more on the medium grip side, its very bumpy, with some decently sized jumps, and also some rollers. as of now, this is what ill be using for my base setup for clay.

I did some testing and this is what i found.

with the friction orings, the diff actually gets very very close to a ball diff in terms of cornering feel, the gear diff is slightly lighter overall by about 2 grams.

I initially expected the gear diff to have more power, because it locks up when you hit the throttle, this turned out to be true, but i think its only because i ran a thicker fluid. 10k paired with 4 friction orings made the car accelerate very quickly, however i dont know how much, if any was caused purely by it being a gear diff. If you were to get a ball diff to be as tight as that, it may have the same amount of power, if not more, however i think the thrust bolt would literally snap before you could get it that tight.

When comparing a lighter diff, to a loose ball diff, the ball diff has more power, there was a large jump that i was having issues clearing on a new layout, and i was running 7k, 4 red orings, and comparing it to a ball diff that was relatively loose, and the ball diff still had more power, and cleared the jumps easier.

i also got this feeling that running the gear diff narrowed the window the car worked in. What i mean by this is, when your struggling to find a setup that works consistently, and the track is constantly changing, the gear diff can cause some inconsistencies in your runs, or even from lap to lap.

remember, i run on high grip, packed clay, not sealed, but its close to that level of grip.

I can for sure see how the mugen diff can work in looser conditions that an.. ae diff for example (no oring tuning) would not work on, however i think that specifically for non-glued clay racing, or on any track that is not turf, or carpet, where it is consistently changing, it is safer, and in all honesty, for stock racing, probably faster to just run a ball diff.

As far as regular setup tuning, heres some stuff i found aswell.

the front camber link, seems to be perfect with 1mm shim on the inside, 2mm on the outside, you never really need to change it in my opinion, maybe if the track is loose, and you want a more grip when you slow down, you can lower the inside ball, or visa versa

as far as the front end goes, ive pretty much ran kit toe, ackerman, axle height, track width, the only things i really feel are adjustment worthy, is the front track width, camber link length, and shocks.

on the rear end, all i have really tuned with was pills, link length, shock mount on the arm, and shocks.

on the rear end, i needed drastic changes from the kit setup, which is to be expected from a 1/10 car if im being honest. i found myself liking my pills to be around .5 down, sometimes maybe remove a little anti squat, maybe if i need the car to roll more go down to 1 down.

the rear link needs to be dramatically shorter for the car to turn in my opinion. In run the inner mount on the bulkhead, and no spacer on the hub, but its flipped so the bump is in. anything longer makes the car push.

the hot topic for me, is the shocks and the rear arm mount location. ive been taking a lot and a lot of time to figure them out, and i think i have a general idea on what works.

Ive been running a thick, 1.7 + 1.8 front piston, paired with a 2x1.8 rear piston

i run 32/30 associated fluid currently. Anything lighter in the front end causes the car to collapse, and loose grip in random spots, but also not turn (at least in higher bite conditions), and just makes you want to hurl it at a wall. Once i went back to 32 wt i was waaaay happier.

rear droop is also a big thing for me, i dont really like to run more than 30mm (0 eyelet) because it will have a similar effect to the thin front shock oil.
I have been running the 1up springs, it just makes tuning easier due to avalibility, im sure the mugen ones are good aswell.

i typically have been running a red in the front, and a gold in the rear, i like the rear shock on the outside arm mount, this makes the car have significantly more steering compared to the inside hole. When i did run the inside hole i ran a 1up blue, maybe a softer spring on the inside mount would allow for more steering? I honestly havent tried it yet, so feel free to try it yourself.