with big 3 you should be safe...id wire a volt meter to read off the amp...i run my DD M1 in my Saleen mustang with under drive pullies at half ..been doing so for over a year now and no issuesI have a stock alt and no big 3 but I am running 0 gage royal excellence welding cable. So I Idk if going below 1 ohm be a good idea.