I had the Shogun Lectri-Charge. It is more of a voltage maintainer that a charger in my opinion. I sold mine and put a GM altenator on the car. The problem with racecars is they don't run enough to recharge the battery if you are starting and stopping a lot. Like moving through the staging lanes. I run 1 battery. I will still put a charger on occasionally.
I also use a Battery Tender. If you have an outlet near where you store your car, I highly recommend it.
http://www.racingjunk.com/category/1...ry-Tender.html