This past Friday I hopped on to a flight to Indianapolis, IN, so that I could attend the International Motorsports Industry Show there. Known as IMIS, it is an annual showcase of racing products and fabrication gear open only to those directly involved in racing.
It was recently announced that both IMIS and PRI (Performance Racing Industry, another racing technology event located in Orlando, FL, this year) have both been purchased by SEMA (Specialty Equipment Market Association) and hence forth the two events will be consolidated into one and held in Indianapolis, IN, next year.
Since this show is not open to the general public I was excited to be able to attend for you folks and share the experience. And what an experience it was…
The convention center allowed vendors a tremendous space to show off their product in and also included seminars on various race related subjects.
I spent a lot of Friday afternoon traveling up and down the aisles checking out the many displays and talking with the vendors that come from all over. Sure, all the big names were there, but there were many manufacturers, suppliers, fabricators, etc., that you would not be familiar with unless you were part of a racing team.
Here are a few representative shots:
I managed to sit in on a few seminars on Saturday and it was impressive the breadth of subject matter that was covered. Things that you would expect such as in-depth coverage of fuel injection (Kinsler Fuel Injection), or brake system basics (Wilwood Engineering). There were also seminars on subjects such as social media and Internet marketing (Avitus Group).
One of the most interesting new developments shown at this show was Hyperco’s carbon fiber spring replacement.
This is a revolutionary change in springing systems. Hyperco has been testing this in racing for at least two years and the Indy Racing series has started testing this product for potential use in their series.
It looks like a series of cupped carbon fiber discs stacked and mounted just as you would a standard helical spring, say in a coil-over shock configuration. While certainly carbon fiber is known for being very light weight the properties of Hyperco’s solution goes way beyond just weight savings.
If you look at your typical helical spring and think of it being compressed and then rebounding it may seem like a perfectly adequate solution to having a suspension on a race car, and it has been so for decades. But helical springs have some drawbacks.
Take a spring out of a click-type pen and put it between your fingers.
As you compress it watch what happens…
It deflects. No, I’m not doing this on purpose, try it yourself.
As the spring is compressed a lot of things are happening. First the top and bottom surfaces are trying to rotate. The coils themselves are being twisted at the same time as they try to store energy. The helical spring tries to resist compression so it pushes out and creates an enormous side load on the shock absorber (spring dampener for those of you folks on the other side of the Atlantic) rod. This can be to the tune of 1000 pounds of force pushing the shock rod sideways creating high levels of friction at the seal and piston end of the shock. These side loads result in an unwanted and inconsistent additional spring rate on top of the helical spring’s own rate.
That is not to say the helical spring manufacturers haven’t gone to great lengths to design springs to try to minimize this property, but they have not eliminated it. Until this Hyperco development.
The springs made from these stacks of carbon fiber discs produce a consistent spring rate with zero side load to the joy of shock manufacturers and suspension tuners.
With the side load problem eliminated it also results in lower spring rates being required since the side load friction is eliminated.
So you might be imagining that this is a very expensive solution, and it is, sort of.
A set of these will cost over $1000 per corner. Not a trivial expense. But put it in the context of the typical race car and you realize that each corner might require a half a dozen or more springs of different rates to accommodate different tracks. The cost of those helical springs of steel might cost in the range of $150 or more each, and if the team opts for titanium springs it is over $1000 each spring. The Hyperco carbon fiber washers can be configured into hundreds of different rates. Now that ends up being more cost effective than even steel springs.
Metal springs also can reach their elastic limit and fail. What I mean by this is that when a metal spring is doing its job it is bending, twisting, and generating a lot of heat and that means at some point it can fail. Take a common paperclip and bend it back and forth and eventually it will fail and break. The same thing can happen with a metal spring.
In a race situation this can be catastrophic. At a minimum putting your car out of the race.
That is not to say that the carbon discs cannot fail, they can. But the failure mode is not a sudden one. They will start to delaminate in a comparatively gentle fashion and can be replaced between races.
This is a game changer and you may eventually see the helical spring replaced in racing. It is happening already. Formula 1 teams have started using them as well as a few in sports car racing.
So you might ask yourself, “When will these be available on road cars?”
The engineer at Hyperco told me that every major automobile manufacturer is interested in learning more about their product and its potential application on road cars. I expect that in the not too distant future you will see them on cars like Ferrari and Porsche. Eventually, as the technology matures and the cost to produce goes down, you will see them used in many more cars. But that is the future.
And you saw it here.