Can I use a RED top optima battery for in motor compartment and then loop it to a YELLOW top Optima battery in the trunk for my audio stuff? Will my alt. charge them both correctly even though they are dif. kinds of batteries?? I plan on wiring them + to + and - to there repected normal grounding spots. Is this the correct way to wire them?

thats what i have in my car and it works fine

i wouldnt really recomend it. it can be done, but there is less of a chance of something going wrong if you run the exact same kind of battery. you also want to make sure the batteries are both new and never been used.

if you wire both batteries in parrallel with your alternator, it will charge them both. the reason i said i wouldnt recomend doing it with different batteries is if the load that the battery puts on your alterantor while charging arent the same, one battery may not charge properly or you could possibly fry your alternator. if the resistance of the batteries is the same, which will be more likely if they are the same battery, then all should be well.



Injection is nice but id rather be BLOWN!

If you would like to do that get yourself a dual battery isolator and wire it up according to the instructions then both will charge correctly AND it will not let the audio equipment suck down the starting battery

Um, no need for the isolator. I know I can vouch for not using it, as well as a few other guys on here. No problems with different batteries - I have an everstart maxx under the hood, and i'm going to pick up an everstart maxx marine for the trunk!

Then if I am going to run 2 of the same batteries, should I run the RED top or the YELLOW top? and does anyone have the part numbers (cranking amps, ect.) on which batteries I should get?

only reason you need two batteries at all is if you're running the stereo for a long time while off, like a whole day.

these are the specs


yellow top
Length: 254 mm
Width: 173 mm
Height: 195 mm
Minimum weight (kg): 19,9 kg
Nominal Voltage: 12 V
Cranking Amps (SAE): 870 CA
Cold Cranking Amps (SAE): 650 CCA
Cold Cranking Amps (EN): 690 CCA
Reserve Capacity: 120 minutes
Capacity (C/20 rate): 55 Ah
Internal Resistance: 2,8 mOhm


red top
Length: 254 mm
Width: 174 mm
Height: 195 mm
Minimum weight (kg): 17,2
Nominal Voltage: 12
Cranking Amps (SAE): 980
Cold Cranking Amps (SAE): 800
Cold Cranking Amps (EN): 815
Reserve Capacity: 104 minutes
Capacity (C/20 rate): 50Ah
Internal Resistance: 3,0 mOhm


14.82 @ 97 mph

Jasonoshawaz24 wrote:only reason you need two batteries at all is if you're running the stereo for a long time while off, like a whole day.

that is not ture at all, do a little research and don't post on stuff you don't know anything about.

in my car i have a 180 amp alternator, red top under the hood and yellow in the trunk.

the reason i have 2 battery's because my alternator does not put out the amount of current (amp's) i need for my system. right now with my radio on for a long time at full tilt i don't go below 11.8-12 volt's and with 1 battery it goes down around 10 volts.

in a few weeks im goin to run a 300 amp alternator red under the hood and 2 or 3 everstart maxx marine batterys in the trunk. when i get my new amps im goin to try out db drag's bass race so i need as much power as i can for 30 sec's.

Maxx Marine – Part # MAXX-29

• 875 Cranking Amps
• 205 Minutes Reserve Capacity
• 125 Amp Hour Rating
• High performance all-purpose marine
• Faster full recharge ability
• 675 Cold Cranking Amps
• Overall dimensions: (LxWxH)
13-1/8" x 6-3/4" x 9-1/8"

Maxx Marine > Optima Yellowtop

Also is the price

69.99 for a Maxx Marine vs ~150+ for a yellowtop.

why is there such a price difference for the two batteries if the maxx marine is better than the yellowtop


Im not a starfish, It doesnt grow back