I’m all about using great parts that do the job and do it well. But sometimes those parts are either unavailable or out of the budget. And sometimes it is just fun to see if you can make something work that most people wouldn’t try. With that said, this project here is electrical and that can be a potential problem if you are not confident in your abilities and if your other electrical system components are not up to the task of higher voltage. We are not endorsing or encouraging you to do something you aren’t comfortable or qualified to do, so watch and try the rest at your own risk.
With that out of the way, check out this cool thing that you can do with your own alternator!
Learn how I made a stock LS alternator charge my 14v battery at 16v ! You could use this to tweak a 12v battery charging to 14+ but use caution as you can over charge a battery also! Proceed at your own risk. Not responsible for any issues arising from this experiment. If you have an “S” “Sensing” wire on your alternator, you can do this too! Link to assortment I bought. https://www.amazon.com/gp/aw/d/B07VJ5… 3k ohm would be perfect for 16v charging. The 5k ohm I used is a bit sensitive on adjustments but does work. 1k ohm should work well for standard 12v battery.