Is there any possible way to run 3000wrms on a stock 90a alternator with secondary a second battery? a H/O alt is out of the question no manufactures make them for my car. Currently I'm running around 1800wrms with a bit of voltage drop without a second battery. it drops to 13.8 while on highway and at idle 12.9. If I could upgrade my alt I would but no body makes anything for the car. A universal alt is out of the question too cuz it has a stock 3 pin harness not just a power on the stock alt. So would this even be possible with a battery like the xs power D3100 as a second battery in the rear to achieve a goal of 3000wrms.

 

A second battery will not fix your problem. I suggest you try and find a automobile electrical shop that builds/rebuilds starters and alternators. See if they can build you a high output alt for your car. I had an old 68 catalina and genco took mine and made it a 150 amp h/o.

other option... buy a different car? Lol