2012 Mazda 3 GX MT5 non sky
Oh well ... i got it now so im going to use it.since you're adding extra weight in an undesirable location (ahead of front wheels), then i agree, compensating by reducing weight from the battery will be very helpful in reducing dive under braking & maintaining steering lightness. since LiFePO4 doesn't offgas like SLA, you could even relocate the battery to the cabin or trunk for an even more dramatic difference. though you would need heavy wiring for the relocation
the peeps over at the miata forum have been dabbling with lightweight batteries as well, check it out: Programmable Search Engine
they don't seem to like shorai batteries, fyi @JoeMini
I think before you start to move stuff around the car to different locations you should get the cars 4 corners weighted.
Pulling weight out is great becuase will weight less overall (HP to weight) . Going around corners fast you want your car balanced.
Ideally .... coilovers is the way to go if you want to attain a more balanced car. On my car every wheel gap is different.
I had to sit in the car for 2 hours while they adjusted and adjusted (with myself in drivers seat) until all 4 corners were the same weight.