I'm looking for a good battery upgrade for my Corvette. I'm concerned about "off gassing" into the cabin as well as weight. What are the different types of batteries, and are some better than others?
Via the Internet
When it comes to performance upgrades, the battery-one of the most critical components of any vehicle-is often overlooked. In addition to commonly discussed specifications such as cranking amps, the weight and output of the battery can have a noticeable effect on the operation of any Corvette model.
Thanks to knowledge gained from the racing industry, there have been many technological breakthroughs in the battery world. One of the most exciting outcomes has been the development of street-car batteries that utilize racing technology, making them lighter, more powerful, and more reliable. Braille Batteries, based in Sarasota, Florida, offers an American-made product that has been proven in racing and is also a welcome upgrade for daily driven vehicles. Braille offers a full line of products, from an amazingly small, two-pound Micro-Lite lithium battery to fullsize, 100-amp hour Endurance models featuring the same performance as batteries used by our favorite racing teams. More on that in a moment.
The way a battery is designed has considerable bearing on how well it can be expected to work. All batteries must be reliable and also perform two main functions: energy storage and energy release. Sounds simple, right? Well, it should be, but production cost is always a factor, resulting in a wide range of product offerings at different price points. It's the same with the automotive industry. While the battery that's installed in your new Corvette is a quality product, there are many good reasons to spend more for a premium offering when the factory unit reaches the end of its service life.
In today's market there are a plethora of battery options. To determine which one is right for you, there are a few questions that must be answered. For example, How much amperage do I need? Am I looking for a lighter-weight battery? How much am I willing to spend? Understanding the composition and performance of batteries will provide you with the answers to your questions.
Battery ratings are important for ensuring that you get the right level of starting power for your application. To determine this rating, batteries are tested for their cranking performance at different temperatures and their capacity under various loads. Commonly called cranking amps, cranking performance is the amount of electrical current it takes to turn over the starter motor.
Back in the day of carbureted vehicles, the industry standard for cranking batteries was 30 seconds at 0 degrees (measured in cold cranking amps, or CCA). In today's market there is a more effective test that better represents the condition of the vehicles we drive. Pulse Cranking Amps (PCA) are measured at 77 degrees for specific times below the 30-second standard. Keep this in mind when you make performance upgrades. Check the PCA ratings to determine how your Vette will respond in race conditions and balance this with the CCA rating for year-round usage. Be aware of batteries rated in "max amps." There are some cases where max amps are simply the short-circuit current of the battery and do not reflect its ability to crank a car.
With cranking performance decided, it's time to look into the different types of batteries available. The standard flooded lead-acid batteries have been in production since the beginning of the automobile. This low-cost option will do a fine job of starting your vehicle, but since it's unsealed and contains caustic liquid that can slosh around, it may not be the best choice for racing. Nor should this type of battery be installed in the passenger compartment of any vehicle, due to off-gassing (the release of hydrogen gases), corrosion, and rust damage. The flooded battery is also the heaviest battery type and therefore would not be the best choice if you're attempting to cut weight.
Sealed lead-acid batteries have been used in Corvettes since the mid '80s. These use the same design as flooded batteries but feature a one-way valve on top to contain the acid during vehicle movement. Although the unit is sealed, it still allows hydrogen gas to escape. If your Corvette has a tube leading from the top of the battery to the outside of the cabin, its purpose is to allow for this off-gassing. These batteries are average for cranking performance and weigh less than the flooded type.
The '80s and '90s brought us "gel cell" (gelled electrolyte) batteries. What made these batteries so desirable was that the acid had been made into a semi-solid mass by incorporating silica-gel additives. With a high-energy storage capacity and a sealed design, these batteries became the mainstay of the racing world and eventually trickled into the automotive mainstream. It was evident that this type of battery offered better safety because there was no spillage when tipped. But as with all new products, time and usage revealed its shortcomings. Subjecting a gel-cell battery to high charging rates could cause off-gassing and result in internal cell damage, or even create potentially explosive conditions in the area surrounding the battery itself. Automotive manufacturers did not select this battery for production due to these inconsistencies in safety and performance.
If you like the idea of a gel battery, do not despair-there are options available. The absorbed glass mat (AGM) type is an excellent choice for your Corvette. These batteries offer zero maintenance, exceptional performance and safety, high energy storage and PCA, and an even safer no-spill design. All this quality does, however, translate into price. While there are AGM batteries available at relatively low price points, remember: you get what you pay for. Like their more-conventional cousins, these cheaper units feature a vent tube that releases hazardous hydrogen gasses into the air.
If you're looking for that perfect battery, you may want to consider Braille Batteries' advanced absorbed glass mat (AAGM) design. These batteries are completely sealed units that keep the oxygen and hydrogen contained inside, obviating the need for vent tubes. Since this type of battery is spill-proof, it's approved for use in passenger compartments and cargo spaces. In place of vent tubes, Braille designed a top cap that slowly releases hydrogen gas at well below the legally mandated 4-percent limit. With a very high cranking-energy-to-weight ratio, AAGM batteries can be built in smaller sizes and still accommodate the performance demands of your Corvette. While these batteries are a little more pricy, we think their advantages make them well worth the extra dough.
Now that you're armed with plenty of information, deciding which battery is best for you should be a little easier.
I have an '00 Corvette that I want to modify for racing only. My question is, What are the benefits of a custom-built or performance crate engine, as compared with modifying my existing powerplant?
Via the Internet
Great question. We contacted our friends at Katech and asked them how they build performance race engines. With 50 championships under their belt, they seem to have the process figured out.
Katech's engine builds begin with looking over the customer's needs and preparing a package that adheres to the rules of the sanctioning body involved. Once the build begins, special detail is given to bore, stroke, connection-rod length, number of cylinders, piston-top volume, deck height, cylinder-head chamber, head gasket, and so on. Then calculations are made for compression ratio, block height, and every other facet of the engine.
Quality-control evaluations are performed at each phase of the build, and every component is tested for performance and durability. To this end, Katech has built motorized drive carts that can be configured to spin the water pump, oil pump, mechanical fuel pump, alternator, and other accessories.
With a wide range of performance crate engines available, Katech is sure to have at least one combination that suits your particular needs. And if you prefer to go for a custom build, the company will work with you to achieve your goals.
While top-quality performance crate engines are never cheap, the advantages of going this route are considerable. In the case of Katech and companies like it, experienced engineers have already done the research and development on every aspect of engine composition. This takes the guesswork out of the process, allowing you to concentrate on your racing adventures.
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