All of the Heritage Jrfuelers use two 12 volt battery in series to start their cars. With just a good Hi-Torque flywheel starter.
We run 15.5 to 16 compression and a 20 amp MSD mag. Now you may get by with a single 12 volt battery with lower compression and your vertex. I have found some great, but not cheap supper light weight batteries, like less than 10 lbs for both batteries. Hayden Wheels sells a remote battery pack, and I could sell just the batteries if you are interested in mounting the batteries in the car. It helps if you should ever kill the motor on the burn-out and no crew member has to haul the battery or cables back to your tow car. We use the remote BatteryPak, because JF is very weight aware. 3.5 lbs per CI with driver. I switched to the Hayden BatteryPak when I found the light batteries because all of our team is over 70. We don't need to charge the battery all week-end, just before we leave for the races, and we have been using the same batterypak for 4 years. I also use a one pound 14 amp battery in the car to power the transbrake and RacePak.
One other thing that might help you, we spin the motor over with out plugs when we 1'st start the car in the morning, that gets our fuel system bled, and oil pressure up. We look for fuel coming out the plug holes.
Jon, 800-624-3803