Here's something I don't recall hearing.. What exactly am I doing to the truck when I add more pins to the center diff? What am I getting out of the truck with zero? As I add more what am I changing?

Oh yeah, 6 pin indoor and 4 outdoor

More pins is locking the front to rear more, like a mechanical locker in a 1:1 truck.
Less pins is like a more open diff or lighter center diff fluid in a 1/8 buggy.

It changes how the power is distributed front to back

So in theory more pins would put more power up front? This is going to make the truck either pull itself around the corner (good) or slide (push)?

Should give you more power sent to the front creating push.

Good to know.. I think that will be next change after shock position. I think i'll go down to one or 2 pins and see what its like.

From marcus' page...

So here is how this works: When accelerating, the spur gear drives the pins into the balls, since both the pin and the ball are hardened (pin is not as hard as the ball) it will slow down the ball since it is a single pressure point instead of a concave pressure point that gives virtually no resistance. This is adjustable via the number of pins you install in the spur gear. You want "thick" dif action load up all 10 pins for a high bite track! you want "thin" dif action (low bite track) take them all out! and anything in between for different track conditions/ grip levels. There are other benefits to this as well, since it is pressure sensitive the harder you accelerate the tighter the dif becomes so you get the same "loose" dif benefits under deceleration, very controlled braking as well as better "in air" adjustments. This IS the ultimate upgrade for your SC10 4x4!

For the hell of it, try zero and ten.
Best way I've found to get a feeling of what an adjustment will do is try both extremes and you get a better idea of what its doing to the vehicle.

Finally did my v2 center diff upgrade. Can't wait to try it out. I was gonna head to the local track to practice but have to wait for the stupid cable guy to come LOL

did a quick run outside, I can feel the difference. I'm at 4 pins now.

word of advice if you drop one of those pins in your carpet you will not find it again, LOL.

fried

tip
most of your push is coming from using the outside hole on rear arm ..

You are half right.
Adjusting the pins does change front/rear power distribution.

More pins gives you more rear hook up relative to the front. Having too many pins can cause a push situation. If this is the case, try reducing the amount of pins in the C-Diff to balance the front/rear drive. The number of pins you run is also going to be affected by what diff fluid you run F/R. This will affect F/R drive balance as well. With the C-Diff, try running 7K Front/5K Rear fluid. If you need more steering, drop the front fluid down to 5K.

Note...for those with the C-Diff, either V1 or V2, change your diff spring often. I changed my spring to the FT V2 spring about a month ago and could tell it was sacked out when I had a lack of rear drive and the front was pulling harder than normal. Threw in new V2 spring and got that rear drive back. Keep spares and change out often. They don't last long but they are only a few $.

You're right

1st thing i'm gonna try Cherry

Now that I think of it, a open diff will send power to the place with the least traction. Usually the front since weight transfers to the rear under acceleration.
A thicker diff (like a posi or mech locker) will apply power equally... more to the rear under acceleration and that would allow more front traction and steering.

Maybe Marcus will get our heads straight on this

I think that goes back to try zero and ten pins to see what it's doing to the truck.

OMG, I dropped one in the living room rug and I spent 10 minutes looking for it. From rubbing the shag to hitting the bottom where it landed to picking the whole rug up and shaking and hitting it upside down. Nothing.
Then my friend caught a glimpse of it and asked if that was it... it was. Pure luck or I would still have 9 pins to tune with

That's my seat of the pants experience, I run less pins outdoor and more pins indoor on a super sticky westcoast raceway clay where I have more traction and steering.