Originally Posted by UN4RACING

Where going to need pics. If its a heat issue like a bad bearing the plastic ones will fail even faster. I find the exacto knife to be a great pointer...LOL Take some calipers to each side. If you document with some facts they will for sure hook you up. You may have to check another kit?

Mine are with a new never used set..
Both are exactly 0.500,5 inches. The bearing will fall out if you tip them over. I would rather them be tighter but so far so good on previous kits. If you have a loose fit and a bad bearing it eats at the inner of the hub. Only fix I can think of is to put a piece of thin paper in there.

I personally would not trade in the option hubs, not going to happen. Avid sells bearings for a buck. I would try that before running plastic hubs. The bearings could be the issue. Put a caliper to them....

My hubs will be sailing toilet paper from them before I trade in my option hubs.

Originally Posted by rmtr

I believe the directions said to use the 5 mm,but they were not labeled. I have seen a couple of guys at my local track using the smaller ones. I assumed the largest was the 5 so that's what I have on. Which ones are you guys using? I believe there were three in the kit? Small , medium ,large ?
What will this change? Thanks in advance for any info!

Originally Posted by BIGSKI15

The kit is build and I started installing electronics late last night. I plugged in a spare 200mm sensor wire which is way too long since I'm sort of a freak about neat wiring. What length do you all use?

Originally Posted by Razathorn

That's not showing the center of gravity is at 24mm. When you raise the car up, the center of gravity goes up too, so that's a bit chicken/egg. I believe what you have encountered is you raised your ride height such that you raised your roll center above ground and now jacking force has reversed. What you have demonstrated was raising the front roll center above ground and its affect on jacking forces.

A more accurate jacking force demonstration of jacking force would be to press at the base of the tires near the contact patch.

Jacking forces are the upward or downward force placed against the chassis due to roll action and chassis geometry. If the roll center is above ground, the jacking forces will raise the chassis. If the roll center is below ground, the jacking forces will suck the car toward the ground.

The b44 platform places the roll center really low due to its nominal ride height, If you try this on a b4 rear, it will actually raise at 24mm ride height, but the center of gravity is well above 24mm on the b4.

Jacking forces are one of those things you rarely consider outside of the initial design of the car. Front roll centers are frequently found below ground and tend to suck the front down and add steering on hard corners. Rear roll centers are frequently found slightly above ground, allowing making the rear suck down on hard corner exit when weight transfer lowers the rear and reverses the jacking forces, while still allowing the rear to unload easily in corner entry. The relative GENERAL location of roll centers are part of the car's design. The final fine tuning position achieved with camber link positions and ball stud washers is just playing in that area.

This is yet another reason one does not vary ride height much from the factory settings -- it jacks up the jacking forces and general location the roll centers should be for the car to behave right in all situations.

Wayne

Originally Posted by UN4RACING

I never change my ball stud shim setting from the stock set up. RAZ will vouch for that. I don't go there. I would have to be desprit. You can't pay me to change it.

Originally Posted by thebomber

Newbie here and very interested in this conversation. Am I close to understanding if I believe the following to be true?

Center of Mass (COM) is the point where you would have to hold the car to have it balance on a single point. By adjusting the ride height, you are not changing the COM only it's position relative to the ground. The higher the ride height the greater the distance between the COM and the contact patch with the gound. This creates a longer moment arm (leverage) increasing the rotational and/or sliding force. Makes it top heavy if you will.

Originally Posted by Razathorn

Which drives me mad to no end. You'll change camber link length, but not ball stud washers?! Changing length changes the same thing as washers, just more extreme and also changes camber rise more.

It's kinda like if you were afraid of 10' ladders, but had no problem base jumping off of buildings with a chute. The mind boggles.

Wayne

Originally Posted by UN4RACING

Yeah right. You where just trying to get me down to the wic first.
That steering lock up sucks. Are you running toe out? Try zero and see if that stops the lock up. If not I have a cure and I can be done with testing it. I think the 2nd fix is zero toe in the front.? All the guys I have talked to that have not had trouble have positive front toe...LOL Walking the pits is scarey sometimes. I have yet to try the zero. I have to rework my set up to get the studs back to box stock to try it and be sure. I did put a vid up I think of what I tried. I will see if I can find it.
More steering, if you like the ballast all I see is trying 22mm rear and 21mm from or even 22/22 21/21. Or even tighten the rear diff to the same as the front. i have to ask though. What are you running on for dirt?

Originally Posted by Razathorn

The center of mass/gravity at each end is what is important for roll center and connecting moment arm.



Well, the ball is a bad example. The "roll center" of a ball is where it contacts the ground. The "roll center" of any simple object is where it contacts the ground. It's not in the center of mass.

What we were talking about was jacking forces, which you honestly don't need to even think about outside of designing a new car or making radical changes, to which I assume you are not planning.

In regard to the roll center and its relation to the center of mass at a given end, simply think of the roll center as a virtual point that does not exist but is effectively where hand is at, holding a broom with a big head. The broom stick is the moment arm. Longer the broom stick, the harder it is for you to keep that broom head from swaying back and forth (more roll). The shorter, the easier to control (less roll). The lower the roll center, the lower your hand, since the center of mass (broom head) does not change. So, a lower roll center makes the moment arm (broom stick exposed) longer, and thus it more readily sways (roll).

Hope that helps.

Originally Posted by Razathorn

For the steering lock-up, even with toe-out, I don't have it when the caster blocks and spindles are new. When they get worn significantly, then yes. I tend to replace those at the first sign of locking up, but if you're having problems when new, a trick I used to layer CA glue up on the caster block where the spindle stop is. I would put some glue down, heat gun it a bit, more glue, heat gun.. etc, until it was too high, then use a small hand file and file it back down to the ideal stop size that caused it to not bind.