Thanks for the detailed response Mike. That is really helpful. I'll try out some of your recommendations on the next practice day. Adding 1mm on front hinge pin blocks sounds interesting as well as using hole 1 on front camber link. I have always been using hole 7 in the front and hole 1 in the back. May be using hole 1 on both will help stabilizing the car.
I'm on hole 1 in front with 1mm under the outer camber link stud. Because that's what the fast locals use. I'm still at the stock hole 3 in the rear with 2mm under the outer camber link.
I have a question about adding 1mm on front hinge pin blocks. Which setting is that affecting exactly? front roll center? toe angle? It'll give a bit of toe out yes. However I don't think that's the point of this set up change. I just want to understand the logic and mechanic of each set up change. it helps me predict how the car should react to it.
Thank you.
So to be clear, I put 1mm under both the forward and backward mounts on the front arms. That will effect track width, shock angle, probably roll center a bit, maybe even ackerman and bump steer for all I know. But the main goal with that change is to widen the front track width. Using 1mm spacers between the wheel and the hex would make a similar change without as many geometry side-effects, and I'm honestly not sure why one approach is preferable than the other. My understanding is that the wider track in front generally takes away some roll, maybe takes away a little grip, stabilizes the car, and makes it harder to flip.
I should start filling out setup sheets to track my changes. But here are some notes from last night's racing:
- I ran the gear diff with 500k traxxas oil all night. It diffed out a lot on corner exit, so I know I was loosing some accelleration there, but it was controllable. I think I had a radio calibration issue that was making it really hard to get on the throttle smoothly that I later sorted out. But overall, the car was much smoother into and through the corners, and was easier to do consistent laps with.
- Started on Spec-R C2.9f/2.5r springs with TRF shocks (with clear silicon o-rings) on AE 35wt oil. That car was decent bit maybe a little nervous. I switched to AE Silver/Green springs on TRF shocks (with 50* tamiya x-rings) with AE 45wt oil, and it was a huge improvement. It really settled the car down, especially in the high-speed transition. I think next time I'll start with 45f/40r, and build the extra set of shocks as 1 pair of 50wt and leave one at 35wt, and experiment with the fluid split.
- I copied another local guy's dynamic brake settings for the Viper ESC. I had it off before. This made it easier to be aggressive on corner entry while still maintaining what little consistency I had

. It was kind of weird in a way. I was used to using a lot of brake to slow down a lot to keep from over-shooting, but I found that I could go into the corner a lot faster if I just trusted the dynamic brake. I need more practice with it to get used to it.
- Late in the night, with the car working decently (better than the driver at least) I reduced front up-travel from my initial setting of 3-3.5mm down to 2-2.5mm. This helped the car on corner exit a lot, really reduced the diffing-out problem, and made the car work even better through the high-speed transition.
- In the last qualifier my fast lap was 14.2x with the average looking to be about 14.7ish. Some bad luck with traffic threw me off my pace so I pulled the car to avoid frustration. The only change between then and my B-main was less front droop and fresh tires. I only did 8 laps in the b-main, because I got caught in an accident in front of me in the first corner dropping to 8th / last place, drove 4-5 smooth laps to get back up to third feeling like I had the pace to at least catch 2nd. Then I caught a dot and traction rolled, then started overdriving and making more mistakes, went all

trying to stay ahead of the people that I didn't want to have to pass again, and eventually just pulled the car. But... during those 4-5 smooth laps, my fast lap was down to 13.9 and the average was looking like it would shape up to be 3-4 tenths faster.
So a good night from the point of view of getting the car working better, but a bad night in terms of actual racing. :/
-Mike
EDIT: I had mistyped hole 3 in front before, it's actually hole 1. Fixed above.