Okay, I drive a 2004 Pontiac Bonneville, has a 140 amp stock alternator. I've done the big 3, I have a XS Power 975 for my second battery. I have 2 SA 15s on a Soundstream TX1.2000D and a JL Audio JX360/4 amp. After I've done everything I'm experiencing minimal voltage drop but after a long while of bumping my amp will go into protect mode because I'm assuming the alt just can't keep up. So basically I've narrowed my options down to a few. Upgrade my alt, Stinger 225 amp for $380, Stinger 275 amp for $450, Mechman 270 amp for $450, or a DC 300 amp for $500. But my other option would be to upgrade my stock battery to a XS Power D3400 for $260. What should I do? Any help would be great, thanks!
Edit: SA's are D4s wired down to 1 ohm