Not really sure of the question. Simply offered what has worked for me. I'm sure you'll be fine with the two batteries and an alternator since I think that's what you've already decided to do. I keep a trickle charger on my Harley and GN too. Good preventative maintenance in my book.
How about the lightweight racing batteries at Jegs http://www.jegs.com/p/Braille-Auto/Braille-No-Weight-Racing-Batteries/763922/10002/-1 Do these give good long term service?
I don't know about them but those big batteries that I put in when I started having Stinger problems kept starting till yesterday when I put the HEI in and started getting spark It was starting to crank slower and with the timing hot it was saying, "Charge Me!" I turned the charger on medium and then I was getting the rink,rink, until I turn the dist enough and it fired right up. Took about 30-40 minutes and they are crankin mad again. It's great when you hit the key and it fires on first compression stroke with open headers. It's like Bang and it starts!
i run a east coast 120 amp , and one red top battery never had a issue , i have made 14 runs in the same weekend still had 13.5 volts
I will check your video when I get home. I'm blocked here at the Chevy dealer. He wouldn't want me to see a Buick pulling a big wheellie now would he?
Most people look at the batteries Cold Cranking Amps as an indication for which battery is better suited for the application. For racing one of the most important specifications is battery capacity which is measured in Amp-Hours or Reserve Capacity minutes. <o></o> The industry standard is how many minutes can you pull a certain amount of current (Amps) from a fully charged battery till the battery voltage drops to 10.5 volts. <o></o> There are 2 main ratings: <o></o> One is based on a 20 hour discharge rate which is the battery amp hour rating. Example: If a battery has a 20 AH rating, you can draw 1 amp for 20 hours till the battery voltage drops to 10.5 volts The other is the Battery Reserve Capacity which is how many minutes it will take to drain the battery down to 10.5 volts at a 25 amp draw at 80 degrees F.<o></o> The Reserve Capacity discharge rating is closer to racing reality and should be the spec to be considered. If a car is running electric fans, electric fuel pump and possibly an electric water pump, you need capacity even if you are running an alternator so you can run the fans and water pump in the pits to cool the engine between rounds. Obviously if you are running a total loss system (No alternator) you want a lot a capacity and it has been our experience that a 120 minute reserve is the least amount that you want to have especially when you are hot lapping near the final rounds with no time to recharge. For most lead acid batteries the weight break for capacity is around 2.5 minutes per pound. At some point there is a trade for capacity versus weight added to the car.<o></o> So when you see a light weight lead acid battery, say 20 lbs, even if it has some high Cold Cranking Amp rating the capacity will only be around 50 minutes. Battery weight relates to battery capacity. The standard lead acid battery is the least complicated and least expensive to use.<o></o> The AGM battery has many times more resistance to vibration failure than the standard lead acid and last longer if maintained properly. It also has a slight advantage in power density. We found that the AGM will hold its voltage pretty constant until you reach the end of its capacity. The down side is it cost twice as much and it requires special charging considerations which means a more expensive battery charger. An AGM doesnt like to have its voltage pushed much beyond 15 volts during charging and can be damaged with voltages above 15.5 The charger can deliver a high current as long as the battery temperature stays below 125 degrees F. As soon as the battery voltage approaches 14.5 volts the charger goes into voltage regulated mode and cuts the current back to maintain that voltage level till the battery is near fully charged. Then it is topped off with trickle mode. Over 3 years ago we used the very expensive Lithium battery. At that time the batteries had internal protection for over current and under voltage. We had to send one back because it would shut down intermittently. It looks like they have improved since then. They have 2 to 3 times more energy density than the lead acid and they can be recharged very quickly. If you absolutely need the light weight and the budget permits then this is the way to go.<o></o> For our present racing needs where we dont need the weight reduction, the AGM works best. The voltage only varies a few tenths from no load to running loads and we get excellent service life. If you are running a car that is strictly for racing only, then a 16 volt AGM battery is absolutely the way to go. The starter works much better and the ignition system is able to get the energy it needs to provide a stronger spark at high rpms. If you are running an EFI system, the higher voltage really helps the injector response time. The only thing you need to remember is to be sure the power is turned off to the car when charging because the battery voltage will exceed 18 volts and even though most of the electronic equipment on board is rated for 20 volts it is better not to push it. I must add, when looking at purchasing a new battery, check the date code. We like to buy batteries that are only a few months old. Paul<o></o>
