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This build is awesome!! Be fun to race this at an event where Brian is at. I bet he would want to take it for a rip.

There were many different ones out. Box stock were 30 I think, 25 are the desirable ones (and stupid hard to find). Take a shot, front wheel off, from the side. Show the angle of the shock tower in relation to the caster block. Directly in line is 30 (IIRC).

soniccj5 wrote:This build is awesome!! Be fun to race this at an event where Brian is at. I bet he would want to take it for a rip.

Let him take it for a rip? Hell I'd give Brian the car if he wanted, but I'd ask 3 things:
1) He race it as a pro one at least time (not sure associated would let him as a sponsor, so I could let this slide).
2) Autograph my 2 worlds cars.
3) Get my picture taken with him and the worlds car he signed.

JK Racing wrote:There were many different ones out. Box stock were 30 I think, 25 are the desirable ones (and stupid hard to find). Take a shot, front wheel off, from the side. Show the angle of the shock tower in relation to the caster block. Directly in line is 30 (IIRC).

JK,

Good advice on the shock tower angle, I never thought of that! Here are the pics. Notice the pic I took with the strait edge as a reference to how much the wheel stub kicks up and full turn lock. It's awful! Any advice?

I started the initial suspension tuning and geometry correction, mainly the "caster" issue. It required the following items to be purchased. I updated the master BOM:
Rear green Spring 6480
Front green spring 7427
#2 shock pistons 6465
Shock down stops 6466
Shock shaft 6459 (qty 2)
B4.1 front Caster blocks 9580
Hinge pin 6227
25wt and 35wt oil
After conducting some research I found a good starting point for the suspension tuning:
Green springs should be used on all 4 corners, #2 shock pistons should be used on all shocks, 25wt oil up front and 30wt out back. The 1.32 SC10 shocks out back were just too long for my application, so I took the 1.02 shafts out of my stock RC10 rear shocks used a small spacer and put them in to the 1.32 SC10 shock bodies. This gave me a pretty good length!
Notice the difference:


Next on the list was to correct the caster issue. After speaking JK Racing it was obvious that 25 degree caster blocks would help the issue, but since they're no longer made and very difficult to find, I kinda hit a road block... Soniccj5 recommended using the B4 25 degree caster blocks. The mod was rather simple and straight forward.
This is what the modified b4 setup looks like:

This is the stock set up:

Final product:

After completing the mod I decided this is a "MUST DO" for all RC10's. It widens the car slightly, nearly corrects all the bump steer issues, increases suspension travel and if the 25 degree caster block are used should increase the tires contact patch through out the turning of the wheels and also increases the amount of overall available turning capability.

This is how it goes together.


The B4 caster block will need to be drilled out to accept the factory 1/8th inch hinge pin.


With that being said the factory hinge pin that goes through the steering block will not be long enough. I found that the hinge pint that goes through the caster block fits just fine, since I had a few extra ones kicking around I just used those. If you want a part number that will work use 6227 which is readily available.


The B4 caster block fit in the A-Arm just fine, but required a very small washer to take up some of the slack. The steering block required a larger spacer.


The cool thing is since I was reworking my shocks I discovered that the down stops used inside the shocks were the exact size spacers I needed for the steering! So simply use associated # 6466 for your spacers!


So the next part is to clearance the upper part of the caster block so the e-clip can be used. This really isn't necessary since you have the steering block set screw in the wheel stub axle, but I like redundancy! Below is a pic:


Finally the last step is to clearance the A-arm. Due to the increased steering capability the nut holding the ball stud hits:




Hope this helps the next guy!

You should've let those arms in the dye a lot longer.

scr8p wrote:You should've let those arms in the dye a lot longer.

It's the flash on the camera making them look like that. They are jet black for sure

Also, the rear SC10 shocks are 1.39, not 1.32 But using a 1.02 shaft is the answer, either way.

You could have used B4/T4 steering blocks with T4 Axles like I have on my Klien arm car (Shown with 30's, I have since changed them to 25's):

Orange wrote:You could have used B4/T4 steering blocks with T4 Axles like I have on my Klien arm car (Shown with 30's, I have since changed them to 25's):

Very nice!!! Awesome idea! Keep em coming! I'm curious if you can post a picture of the front of your car/set up? I want to look and see if the turnbuckles are parallel with one another, to see if it is as effective at removing the bump steer. THANX!!!!

You have to use a longer ballstud with spacers under it. Pretty sure I have about 3mm's under it. Its nothing new, we did the same thing bitd up until even today with the B4.2 that comes stock with a 3mm spacer under it.

Even though I have never tried this with an inline axle, I have heard some people talk about turning the B4 Castor blocks around (Left to right, right to left). This may compensate for the steeper steering turnbuckle angle.

Thanx for the great info Orange!!!! Once I get some wheel time I'll try these different tricks and find out what works best.

Can't wait to hear some updates from the track.

Doesn't the b4 have a 25 degree kick up? Which means 25 degree blocks on a standard truck nose give you 30 degrees caster?( they are 'straight up')