Damn great thread! Bringing out some of the best of the best here! Have to agree with CD. Shame on you Jerry "The Pot Stirrer" Peterson! As for data....I deleted those files a year or more ago. I will say that "Electra" was instrumented with piezoelectric accelerometers and charge amplifiers to capture the data. My first efforts were with Richard Ming (Import Developement). I was then approached on a billet design by a young man named Mark DiGrappa. Both offer substantial reduction in deflection (measured at 13 points). Perhaps you should pick up a DiGrappa unit Jer....and then come here for a skii trip! Damn its good to here from people here who have forgotten more then most here will ever know!

Utah

P.S. As for manufacturing your own? Muz (another long timer here) is dead on. First issue is point location of the pivot points. This is a HUGE one. Stiffness is second. And Galvanic Corrosion is third. You still therte Mark.......

 

 

In a former life I worked with a design house that produced some very compelling chassis designs that demonstrated great stiffness at a significantly reduced weight. The key concept was to "box in" areas that would otherwise flex using "triangulation".

For example: Take a cardboard box with no top. A good example would be a shoe box. If you take the two ends of the box and twist it, you will find that you can twist the box a great deal.

Now take two pieces of tape (masking tape, duct tape, whatever) and make an X-brace for the top of the open box from the corners. You will find that the box is much stiffer, even though you don't have a lid on the box. The stiffness is attained by the cross members resisting movement in tension. This is a very efficient way of increasing stiffness. As long as you don't put enough force to break the tape, you have a stiff box. The less movement at the mounting points and the higher the modulus of elasticity of the cross brace, the stiffer the box.

So to make an effective cross brace, you don't need rocket science. You just have to restrict the movement in tension between opposing mounting points on the cross brace as much as possible.

Keep in mind that each material has a different modulus of elasticity and thermal expansion coefficient. The best material to use is steel, but it is also the heaviest. Aluminum is much lighter, but has to be much thicker to make up for the lower modulus. To make the braces stiff enough, you would need to make a steel brace out of a tube design, and an aluminum brace thick. Both designs work well. Do not make it out of plastic, since plastic has a very low modulus of elasticity.

I hope this helps.

 

bwahahahahaha

 

[QUOTE]Originally posted by cdelena

 

[QUOTE]Originally posted by jerrypeterson

 

If the X-brace would have improved turn-in speed even 1 or 2mph, I would have noticed. It didn't, so it came off. It did not improve steady radius turns, and this myth about uneven pavement is just that. Sure, its entirely possible that some cars may actually see a "benefit" but I am inclined to question whether there is another problem being mitigated on those cars.

 

[QUOTE]Originally posted by jerrypeterson:

 

Or it would turn them all into paperweights.

 

UL setup a stock car and a X brace installed car. Sent people out in each not telling them which they were driving...............I believe that most if not all KNEW which one had the X brace.