Lighter eh? When the JRX-Pro came out, I started running 7 cells flat everywhere - even in stock. On a lark, I accidentally left my six cells at home one day and had to improvise. The car handled much better with the additional weight, in effect, I used ballast to help rectify the spring unbalance. And my world got a ton easier once I ditched the 5 link.

Sorry for the hyjack.

I couldn't run a 7 cell. I only raced in the stock class so 6 cells was the limit. I didn't own a 7 cell anyways. Power was so limited on those stock motors and with the loamy tracks you used up lots of power throwing dirt everywhere. My pinion was ultimately chosen around what would allow me to finish the race before the battery dumped. Having a lighter car made the odds of finishing the race higher. It accelerated a little faster too. Our track wasn't very large and it had some pretty tight curves. The tall spikes on the tires easily dug into the dirt in the corners. We had more problems with understeer than oversteer and traction rolling was an unknown in offroad back then.

Since I mentioned it and it was a question that was asked me a week ago, I think I'll bring it up again.

Traction rolling in corners. How do I stop it? When I get a chance I'll get more in depth on this but for now let me give a very quick and easy fix for traction rolling that anyone who has a problem with can implement immediately. Slow down through that corner! You are faster if you get through that corner on your wheels than you are flipping end over end waiting for a corner marshal to put you back on your wheels. If other cars can do it but you can't then there may be some tuning things to work out but immediately before the start of the Main isn't the time to do it. We'll get into that another time.

Which car?

I've always been a tinkerer. Ever since I was a kid. Today figuring things out is a career. I just like to know how and why things work the way they do. I don't always succeed at what I do but I do always learn something from it. That's what really counts.

You don't need 2 or 4 scales. Just a block of wood that is the same height as the scale. Turn the car around to get both ends.

My SC-R is 34.3oz front and 49.2 rear. 41/59

I've tried moving weight back, but lose steering and even worse the truck wants to back flip off of jumps. Our local SCT pro runs the same weights as I do in the same places, so it's not just me.

Yeah, you could. Only hook up six of them! That's what I did. Since I hardwired my batteries in, it was no big deal. I used to run stock 2w and modified truck, and accidentally grabbed the wrong batteries one day. No where in the rules did it say you couldn't have a seventh cell as ballast.

Anyway, the point of this is the car was oversprung in the rear, and the extra cell gave ballast that effectively lowered the spring frequency/wheel rate. I didn't know why it worked then (I do now), but I knew it worked.

SC10FT Ready to race with body, etc.

Front 27.3 37.0% foam plus 1-1/2oz - battery - 25mm foam
Rear 46.47 63.0%
73.77

Front 27 37.3% 1/3 foam - battery - 2/3 foam
Rear 45.3 62.7%
72.3

Front 28.66 38.1% foam plus 3oz - battery forward
Rear 46.6 61.9%
75.26

Front 28.09 38.9% foam back - battery forward
Rear 44.16 61.1%
72.25

Rear of the truck seems loosy goosy off power lately. Not sure if it's because I'm charging harder or playing with weights. Will experiment in qualifying tomorrow.

Traction rolling-
 

Fred, I am anxious to hear what you do. With my 1/8th off-road buggy I would start with tires- something less aggressive. But in the end it seemed like the anti-roll bars helped most. Dropping ride height 2mm was a band aid but sometimes just enough.

At the last race I went to I took a lot of droop out to help with my traction rolling. It worked great. Since the track was farely smoothe it did not affect other areas that I know. I am new to tuning and still learning. looking foward to advice!

I dont know if what i was told applies here or not but if Fred disagrees with me then go with his answer. I will too. Lol. But how traction rolling was described to me when running on road was this. Going into the corner the car is exerting energy on the suspension and chassis. We kept going stiffer with the set ups and sure enough we kept traction rolling. Some of the guys went to cleveland that year and were told to soften the cars. They said the energy created had no where to go when the car was set up too stiff but yet the energy had to go somewhere so over the car went. The chassis and suspension where not effectively doin their jobs. We softened the suspension and sure enough it helped. We still had to tune everything else like the roll centers and such but softening the suspension did provide immediate positive results.

I look forward to reading more from Fred. I used his method and was very pleased.

Chris,

Exactly my experience with the SC-R:

32.4oz front and 48.1oz rear. 40/60

Spent all last Saturday moving weight around trying to find some steering, and that is where I ended up. Handles and jumps like a dream now.

john

Take droop out of car. Simple answer. Usually what i do on high traction tracks first. Limiting roll.

+1 That's what I do, except 3 blocks and one scale. Seems to work well..

Yeah, and that was a 4 minute main with a 1200mah pack. Great times. My first race car was a Hornet. Same Hornet as BDS, as he is my brother. We ran the crap out of that car. Drilled it up to make it lighter, even though it was pretty much underweight, anyways. Ran a Kyosho LeMans 360PT (550can) in the thing. Guys let you break the rules a bit if you are silly enough to be racing a Hornet. The 360PT was a bit hard on the differential.

Next racer was a first gen Kyosho Optima that I ran for a few seasons. That's where the pinion gear could be maximized to kill the battery in about 4 minutes and 20 seconds if you did everything just right. I threw all sorts of go fast goodies at that thing and it ran pretty well when it stayed together. In my teenage wisdom, I never put money into things like ball joints or threadlock, little things that keep you from finishing races with your otherwise world dominating machine...:deathstar:weird:

A matter of mathematics
 

While in the rc world we can weigh corners and measure the dimensions of our suspension geometry. Knowing our spring rates. There would be a mathematical equation to work out spring frequency and hence match front to back. Anybody know it

Fred I didn't realize you were local. I wish I could meet up with you on a practice day and learn from ya.