I don’t know if you’ve been following the presidential campaign stuff lately. It’s actually quite entertaining.

With all the bashing going on and people calling other people liars, it’s hard to know what the truth is and what isn’t.

It’s like what is going on in late model racing lately with the Lucas Oil Series rules changes.

Some say it’s going to save people money others say it’s going to cost people more money.

I’m siding with the group who says it will cost the teams more money. I look at it this way.

The more rules usually creates a situation where teams will need to try harder to find loop holes or just all and all cheat.

First, this will create a situation where shock tuning and shock adjustments will become  more critical. This will mean a shock tuner on staff or customized shocks for each car. The days of having a stock shock or even an aftermarket rebuilder do your shocks will be over.

Shock valving will become specialized and highly guarded secrets. Each team will need to do their own just to keep the secrets.

Valving shocks isn’t too hard. There is a learning curve to figure out what shims do what and what you need to concentrate on for each corner of the car.



By the way, you’ll probably need a dyno and know what to look at when using it. Like I said their not complicated, but some times a small mistake on assembly can make a big difference in valving.

Thanks to the dyno, I caught many mistakes before they made it to the track. I actually think shock valving and building is more complicated and sensitive to error that motor building.

I think one of the least expensive, but still accurate dynos on the market will set you back $4,500.

The only somewhat plausible argument I’ve heard about the rules changes costing more money is that with and increase in traction comes with an added desire for more horsepower. Horsepower isn’t cheap.

But, my argument is that people are buying as much horsepower as possible now. They just cut gear, under carb it, or restrictor plate it to keep from blowing the tires off the car.

The moneys already being spent. Let us get more traction so we can use what is already being paid for.

Ok, I think you’ve enough griping. Let’s get along to something we can actually use to make our cars faster.

I want to explain further why a solid top rod, without any cushion, takes away traction.

First, we need to understand how traction in a pneumatic tire actually works.

 

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In the above picture, you can see that a tire needs to maintain a stretch to make the maximum traction.

Now picture your car going over bumps. With a solid rod, the car goes up the leading side of the bump, the tire is stretched more into the side wall because there is no real suspension on a solid rod.

As the tire travels over the top and down the other side the tire is floating free in the air momentarily or on smaller bumps the stretch comes out of the tire.

When the left rear on a four bar is locked  on the top rod the tire will only have maybe half the traction as it should just because it is continually going up and down over bumps.

Now we know that jacking up the left rear will put more aerodynamic downforce on that corner. Depending on us keeping the air out from under the car. But, thats a whole different story and another topic for another day.

So, lets jack up the left rear of our car with top rod drop. Now how do we get all the traction back into the left rear since the suspension is solid?

You don’t.

Or, you’re not supposed to according to the new rules.

The rules have been tightened so much that now we will really have to dig and spend more. If we even choose to patronize that series.

There are some basic things we can do to get us closer.

First, we need to concentrate on taking all the binds out of the suspension. In my next article I address several things like greasable rod ends and ‘flextures’.

But, right now, lets talk about something I’ve been considering for quite a while.

Would a double bearing set up work to reduce friction in the suspension. I’m thinking along the lines of a rod end connected to a radial bearing in the mount. If you think about stiction as the amount of force it takes to set something at rest into motion. By adding another bearing you could ideally cut stiction in half,

In the next article I go further into stiction and reducing binds, but this was just a quick idea I’ve been working on to reduce binds in the suspension.

Another thing I must really talk about are birdcages. Now, bearing birdcages have become all the rage. If you have not been around dirt racing for a long period of time, you probably don’t remember a time when there were no bearing birdcages. Everything was greasable birdcages. These things required lots of maintenance.

Before every race they needed to be greased and rotated to distribute the grease evenly around the axle tube. Every two or three races they needed to be disassembled and cleaned.

It looks like greasable birdcages are making a comeback. I was looking at a car recently and noticed a problem that was overlooked, which back then, was a rule of  thumb to keep these from binding. Setting the proper side play. As the birdcage rotates and heat up they expand and if there is no side play, the birdcages can bind the suspension.

GRT race cars used to use a general rule of thumb of putting a side play of between .080 and .120 thousandths. I used to use a quarter out of my pocket to set the gap. The important thing is to keep a side play gap so the birdcage doesn’t bind.

Could we take it one step further by floating the birdcages on a wedge of oil similar to the bearings in a motor. Wouldn’t this be the ideal in a friction free suspension.

It would require a continuous supply of oil to pressurize the cage  and have it float on the the axle tube. This may be a little beyond the scope of what we could do. It could be quite expensive to implement.

Probably way out of reach of the average race team.

But, it’s an idea to keep us thinking and moving forward.

Take the good ideas and work on them further.

Toss the rest aside.

Be safe and keep reinventing yourself and ideas to make you more successful,

Kevin