Archive for November, 2008


(This article first appeared in the November 2008 issue of SportsCar magazine)

By Philip Royle

You’ve just finished your mid-summer, 30-minute Club race, and you peel yourself out of your racing seat and douse yourself with water in the hopes of cooling off. Your face is red, you’re dripping sweat and you’re lucky to be standing. The worst part is that when you look around, there’s someone that appears full of energy and is ready for another race – if only that were you.

There are tricks to having your body deal with the stresses of a race (i.e.: exercise), but the fact is you’re going to wrap a multi-layer Nomex suit around you, strap yourself into a racecar designed for maximum aerodynamics rather than  ventilation and place yourself in a pretty high-stress situation for an extended period of time. No matter what shape you’re in, when temperatures rise to over 100 degrees in the car, your body is going to react – and that can lead to sweating, a lack of concentration, judgment and reaction errors and possibly even disorientation.

This problem is nothing new. NASA’s space program was dealing with the same issues with the Apollo program in the 1960s. NASA’s solution came in the form of a complete body cooling system, routing liquid filled tubes around the astronauts. If this technology can get us to the moon, surely it must work in a racecar.

The solution

In 1987, Rich Shafer noticed that surgeons needed a way to keep cool during long operations, and that led him to NASA’s space research from nearly 30 years prior. All of this ultimately resulted in the formation of Shafer Enterprises and the invention of the Cool Shirt.

The Cool Shirt consists of a T-shirt with 45 feet of medical grade capillary tubing stitched to the shirt, and that is connected to a water filled cooler; a motor in the cooler then pumps cold water through the shirt, cooling the wearer. Being a racer and a long-time SCCA member, Shafer realized the Cool Shirt’s potential in a racecar, and brackets were made so the system could be strapped into virtually any production-based racecar.

“Once it’s 95 degrees or higher, you get no evaporative cooling at all,” explains Cool Shirt’s John LaDue. “As your body temperature rises, your hypothalamus gland tells your body to send blood to your skin for cooling, [but] if you’re in a 150 degree car, you’re basically not getting rid of any of your body heat.”

According to LaDue, it’s normal for the blood to be sent to the skin for cooling. Usually, the body sends about 4 percent of the blood to be cooled; under extreme conditions, up to 48 percent of your blood can go to the skin.

“When that happens, the blood is being pumped away from vital organs like your heart, your liver and your kidneys. When that much blood is gone from your core, you start to get dizzy and nauseous.”

Another side effect is your decision making process slows, increasing the potential for  mistakes behind the wheel.

“The Cool Shirt holds about 10oz of water and the flow rate is about 24oz of 45 degree water over a period of about one minute,” explains LaDue, noting that water has the ability to cool the body 28 times faster than air. “Covering 40 percent of the body, the cooling effect of the water going through the tubing will cool one cycle of your blood.”

There are several similar setups to the Cool Shirt available from a number of companies, and you can find a few homemade how-tos online. However, we prefer using something tried and true because there are few things more distracting during a race than having ice-cold water dumped in your lap.

Installation and use

The Cool Shirt package that will work for most SCCA Club racers in production-based or GT racecars is the Club 12 system. For $289, you get a 12-quart cooler with a water pump and eight feet of insulated dry disconnect hoses. You’ll also need to order a shirt (Cool Shirt offers Carbon X and Nomex shirts), and if you so choose, you can order the mounting kit, although it’s easy enough to fabricate a bracket.

“You want to make sure to bolt the mounting tray to a section of the frame, not just the floor pan in case you have any kind of high g-force crash situation,” notes LaDue.

The electric pump within the cooler is simple to power. A 12v power source and a ground is all you need, although you’ll probably want to connect this to a switch the driver can operate from within the car.

“Some drivers can actually get too cold with the shirt, so it’s nice to have the flow control on it,” says LaDue, referring to the company’s temperature control switch that slows the flow of water to the driver. “You could also turn the machine off. Most drivers will put in some kind of toggle on/off switch. The disadvantage to that is you get a little bit of a cold shock when it starts up again.”

The 12-quart system will supply enough cooling for around three hours. Cool Shirt also offers a 24 quart system that is good for an estimated six hours.

With the cooler mounted, the motor wired and the insulated tubes threaded to the driver, the only thing left is connecting it to the shirt, which is worn beneath the driver’s racing suit. For that, there are several options.

“You can take the shirt tubes through the suit pocket, you could get a seamstress to make a hole in the side, or a lot of guys simply run it out through the zipper,” says LaDue.

Maintaining the system

“You can drain the cooler using an extra fitting on the cooler, towel it out and let it sit,” says LaDue. “As far as the shirt goes, if you’re using it on a fairly regular basis, we have a maintenance additive, which is an anti-fungal product that we recommend you add to the unit every time, which stops growth from forming in the line.”

Should anything clog the lines, the water flow will slow and the connectors could get plugged. If you’re storing your system for more than 30 days, it is recommended you drain the water completely, which involves blowing air through all the tubes.

Similar to your race suit, the Cool Shirt T-shirt should be washed. “You can put the shirt in a washing machine on the gentle cycle and then put it in the drier,” says LaDue. “It is pre-shrunk cotton with very easy maintenance. You’ll get several hundred washes out of it before you have to do anything to it.”

A driver cooling systems like this could very much be considered a safety item. When your body’s core temperate exceeds certain temperatures, you no longer are operating at your best, and at racetrack speeds, that can be dangerous. The human body was never designed to do some of the tasks we ask of it (sitting in a 130 degree cockpit for 30 minutes while battling for on-track position comes to mind), thus minimizing the impact to the body is a good idea. Be it a home-brew cooling concoction or this pre-packaged Cool Shirt setup, if you race when it’s hot – and who doesn’t – this is one item you’ll never be sorry you installed.

SOURCE:
Cool Shirt, http://www.coolshirt.net

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(This article first appeared in the November 2008 issue of SportsCar magazine)

By Philip Royle

Stopwatches. According to the GCR, these are an acceptable alternative to the use of electronic timers for logging racecar lap times at SCCA Club Racing events. Quoting 5.10.2.D.2 of the GCR: “The stopwatches should time to the nearest 1/100th of a second. The minimum acceptable resolution for a stopwatch is 1/10th of a second. Timers will record the cumulative time of passage for their assigned car(s), then compute and record the individual lap time.”

While the GCR may still consider stopwatches acceptable, virtually all SCCA Club races utilize electronic transponders mounted to the racecars for their timing needs. When the racecar passes over a track-mounted loop, the transponder reports to Timing and Scoring and lap times are automatically generated. Best of all, the transponder system is generally recorded to 1/1000th of a second – far more accurate and consistent than any stopwatch.

Born from requests from the regions, the SCCA placed transponder guidelines in the GCR in 2001, thus standardizing transponder usage across the Club and naming AMB as the transponder company of choice. During the early days of transponders, however, SCCA regions wanting to utilize transponders for their timing needs had to purchase fleets of the transponders and rent them to racers for the weekend, as few racers owned their own transponders.

As time progressed, racers began purchasing their own transponders, permanently mounting them in their racecars (a movement aided in part by AMB launching its race tracking Web site, MyLaps.com). Racers owning their own transponders helped alleviate some of the drain on the regions, as the regions no longer had to maintain a slew of rental transponders. However, racers were left with the task of figuring out which transponder would best fit their needs – and then there was the problem of mounting it.

What’s right for you

AMB sells two Club Racing transponders: the TranX260 rechargeable and the TranX260 direct powered transponder. The rechargeable unit is the one most regions rent to racers. The rechargeable units can operate for up to five days on a single charge and offer the benefit of not having any external wires to worry about – 30 seconds and a couple zip-ties is all that’s needed to mount this transponder.

The other option is the direct powered transponder, which must be wired into the car’s power supply. “Generally speaking, the direct power transponder is a huge advantage in that it’s on, it works and you never have to think about it for years,” explains Bill Skibbe, sales and support engineer for AMB. “The advantage of a rechargeable unit would be for someone who wants to use [the transponder] on several cars at different occasions. This way he doesn’t have to have multiple transponders.”

While the rechargeable unit does have its advantages, most SCCA Club Racers would probably benefit from the direct powered transponder, as it is very much a “set it and forget it” item – there’s nothing worse than having to rent a transponder because you forgot to charge yours.

Tricks to the trade

“The way the transponder works is that it generates a magnetic field,” says Skibbe. “Any kind of iron or magnetic metal around [the transponder] would distort the field and weaken it.” To keep the transponder’s signal strong, you want to make sure the transponder is not mounted above carbon fiber or metal, and make sure the correct side points to the track.

“Mounting it above fiberglass or Kevlar is ok,” says Skibbe. “Generally, [mounting the transponder above] plastic is no problem – the bracket is plastic. Part of the reason for the bracket being plastic is to insulate it from the metal it’s going to be attached to.”

According to Skibbe, the normal mounting location for a transponder is at the front of the car, either in the fender or behind the front valance but away from flying debris. “It’s [usually] easiest to get power to the transponder from a location up front.”

The ideal minimum mounting height for the transponder is one foot off the track, with a maximum height of two feet. “We’ve seen installations from guys in formula cars who believe they get a better transponder reading by getting it as close to the track as possible,” says Skibbe, “but what that does is reduce the amount of contact time the transponder has with the loop. Between one to two feet gives you the most identifying hits and the best definition of the signal in order for the decoder to process the data and give you an accurate time.”

If you purchased or rented a rechargeable transponder, there is no wiring; a direct powered transponder requires 10-30v DC power and a ground. It’s recommended you tap into a fused wire that is powered when the ignition is turned on.

Spend a few minutes in the paddock and you’ll undoubtedly find someone that has wired their direct powered transponder into a switch so they can turn the transponder off while the car is on.

“Originally, a lot of guys mistakenly thought a transponder would drain the battery if it were on all the time,” says Skibbe, “but the power draw from the transponder is so small that you can’t possibly see the affects throughout the day. Having the ability to turn the transponder on and off within the car is really unnecessary and leads to forgetting to turn it on.” Skibbe also notes that a switch can also introduce a point of failure.

The only catch is pricing. The AMB TranX260 rechargeable unit costs $420, with the direct powered unit coming in at $380. Considering many regions rent transponders for $50-$60 a weekend, it only takes seven weekends for a transponder to pay for itself – and by the SCCA picking a transponder standard, racers can safely purchase one of these transponders with the knowledge that it will work at almost every SCCA Club Racing event anywhere in the country.

Real world installation

We chose to install the TranX260 direct powered transponder in one of our Club Racing project cars, as we liked the idea of never having to remember to charge the unit. We opted to mount the transponder at the front of the car just in front of the radiator support near the factory horn mount. A metal bracket was fabricated, the transponder was bolted to the bracket and the bracket was attached to the car via an existing hole that was already threaded.

The AMB direct powered transponder comes with several feet of wiring you can trim to fit your needs. We tapped into a12v power line that’s live when the ignition is on, and we grounded the black wire. If you need to add wire, make sure to use a sufficiently thick gauge. When the transponder is powered, a green LED illuminates on the front of the transponder.

Once we’d found the ideal mounting location, installation took 15 minutes. With our mounting location, the bottom of the transponder sits 18 inches off the ground – perfectly located between the acceptable height of one to two feet. The transponder also has no metal below it, allowing for a clean signal.

Prior to this, we’d been renting a TranX260 rechargeable transponder from our SCCA region for $60 a weekend. Using the same transponder number now means we can utilize one of AMB’s online features: MyLaps.com.

MyLaps allows racers to view lap charts and information about their races online. Once you’re registered, you can view a variety of charts packed with information about your race weekend. While MyLaps is no replacement for data acquisition (and keep in mind, the race results printed on MyLaps are not official results), the information is very useful and it makes for easy tracking of your racing history.

SOURCE:
AMB, http://www.amb-it.com

(This article first appeared in the November 2008 issue of SportsCar magazine)
By Jason Isley

Ask any road racer – amateur or professional – what their biggest fear associated with a crash is and the answer will probably be a fire. A good quality driver’s suit and underwear are the first line of defense for the driver, but there are additional tools you can use to protect yourself – and your car – in the even of a fire.

The GCR currently allows for a 2lb. handheld fire extinguisher to be used in a number of Club Racing classes, and we have been using this allowance in one of our project cars. While the small extinguisher meets the letter of the rules, and we are certain it could prove useful when tackling a small fire, we do not like the idea of getting close enough to a fire to actually use the extinguisher – we hope to be out of the car and far away from the flames, which essentially makes the extinguisher a cosmetic item. Consequently, a complete fire system was in order.

As items like a HANS and a radio system are added, egress time is slowed, reducing the amount of time the driver may have to use the handheld fire extinguisher. A fire system protects the car and driver better than a handheld extinguisher as the system does the work of fighting the fire even as the driver is in the process of escaping.

Your options

When it comes to on-board fire systems you typically have two choices, Halon or Aqueous Film Forming Foam (AFFF). Halon is one of the most common types of extinguishers in automotive applications. Halon is stored under pressure in a liquid state and once discharged the combination of liquid and gas work to smother the flames. A nice feature of Halon systems is that almost no cleanup is required if you discharge the system; a drawback is that due to some of the ingredients being labeled as harmful to the ozone layer, production of Halon was banned in most countries in 1994.

If you have a Halon system, or are thinking about purchasing one, don’t let the production ban deter you. There is still a large surplus of Halon available – over 30 years worth, according to some sources – as well as safe alternatives such as FE-36, which is in production. It is also noteworthy that many experts agree that chlorofluorocarbons do more harm to the ozone layer than Halon due to the volume used.

Unlike Halon, AFFF is stored as a liquid and discharges as foam. The AFFF concentrate is a water based, synthetic animal protein, and the foam is biodegradable, non-toxic and cleans up with water. The most common AFFF applications are found as a pressurized tank, charged by nitrogen or oxygen.

The reality is both Halon and AFFF are more than adequate to help protect you and your car, leaving a lot of the decision to personal preference. After researching the options, we opted for an AFFF system for its environmental advantages.

Installing the system

Emergency Suppression Systems (ESS) offers an AFFF system that is non-pressurized and meets SCCA requirements. The ESS system uses an AFFF concentrate, which is combined in the storage cylinder with water. The activating agent comes from an externally mounted liquid filled C02 cartridge. When the system’s T handle activator is pulled, the C02 cartridge is pierced allowing the C02 to mix with the AFFF and water in the tank, creating foam that resembles shaving cream.

The ESS system is user rechargeable, so if you ever have to use it (or you accidentally pull the T handle) you can recharge it yourself – which is a great cost savings and convenience. The ESS system is also priced around $50 less than a competitive Halon system. The shelf life of the ESS system is also nice – when mixed, ESS states that its solution is good for ten years, but recommends replacing it after five to seven years.

The ESS 2.3-liter system was a perfect fit for our application. The 2.3 system is designed to give two areas of coverage – the driver and the engine compartment. The AFFF foam is delivered via three T-style nozzles, one on the driver and two covering the engine.

Beyond basic hand tools, the only item we had to source for the installation was a flaring tool, to flare the end of the 1/4-inch aluminum tubing. If you have not used a flaring tool before, it is a good idea to pick up a scrap piece of tubing from you local hardware store to practice on.

The first step is to pick a location to mount the cylinder. The cylinder should be mounted horizontally in the car, with the head facing the front of the car to optimize the foam delivery. Beside that, the only mounting limitation is you must mount the tank within six feet of the actuating cable pull handle. However, it is a good idea to minimize any unusually sharp bends in either the actuating cable or the discharge lines. It is also a good idea to mount the cylinder with the C02 cartridge on top, this way if you should have to remove the C02 unit for a tech inspector, you will minimize any AFFF loss.

The T handle is the next item to install. This handle must be mounted within easy reach of a belted driver. We chose to fabricate a panel to fill the space once occupied by the factory radio and we placed a metal bar behind the panel to create a sturdy mounting point for the handle.

Back to the ESS cylinder, there are two outlets at the head of the cylinder. From these outlets will run aluminum tubing to both the driver and engine compartment.

Working with the aluminum tubing is simple as the tubing is soft enough to bend with your hands – just be sure to avoid sharp bends or pinching the tubes. The tubing should be secured with the supplied padded clamps, and steps should be taken to prevent the tubing from rubbing on anything that could wear a hole in it over time.

The driver’s discharge nozzle should be positioned to provide coverage of the lower torso, legs and feet. Typically, the side of the center console or transmission tunnel is a good place for this outlet; it should be about knee high.

Depending on your car, locating the bulkhead T can be a difficult task. Once you have found a suitable location to pass through the firewall you can select a location for the two nozzles. Typically against the firewall, one on the passenger’s side and the other on the driver’s will offer adequate coverage. These nozzles should be angled to face slightly toward each other to provide overlapping coverage of the engine compartment.

Once the hardware has been completely installed, you must remove the cylinder and fill it with the AFFF solution and water. Doing this step last makes the cylinder easier to work with not only because it weighs less, but there is no chance of accidentally discharging the system during the installation. This is also the most dangerous part of the installation. When mixed with water, the AFFF solution is perfectly safe, but in its raw state it can be harmful to your eyes, so safety glasses are a must.

The process is simple: Fill the cylinder with the prescribed amount of water and add the AFFF solution. During this process, make sure to have the C02 cartridge in place or fluid will escape from the cylinder. Once filled, reinstall the cylinder, hook up the T handle and nozzle lines, and you are done.

According to Thomas Turner, president of ESS, if you have followed the instructions your system will be ready to go with no testing needed. We did ask Turner if there was a way to verify the fittings and nozzles were aimed correctly and had no leaks without discharging the tank. Turner informed us we could run water through the lines – this would also ensure you have not left any debris in the lines from the flaring process and that all your fittings are tight. He did reiterate, however, that testing is not necessary if you installed everything as shown in the instructions.

While installation of the ESS system is relatively easy, if you have any reservations about your ability to install the system (or any fire system), contact a professional for the installation. It is essential that the system works properly, and it is very likely you will not know if you did something wrong until the moment the everything has to work.

With the fire system installed, we are far more confident of our and the car’s safety than when we were merely meeting the GCR’s extinguisher requirements. As for testing our system, while we would like to see what it is like when it goes off, we have been unable to convince the boss to pull the trigger.

SOURCES:
Emergency Suppression Systems INC., http://www.essfire.com
Environmental Protection Agency, http://www.epa.gov