Is there any problem with putting a small size optima yellow top (out of a honda) into an STi?
Thanks,
Mike

 

Good question. The smaller the battery becomes, the less cold-cranking power and reserve capacity it will have. Going to the smallest battery to save weight is great for racing, but if you ever leave any custom-wired accessories on after shutting off the ignition, or leave a sound system (assuming you've got one) playing while sitting with the engine off, or develop a short in the wiring system, or suffer charging system failure you may find yourself stranded. I would go with the recommended size for your car.

I had alternator failure on an old car and was able to drive almost 85 miles on just the battery power alone. I had to turn off the headlamps during the last few miles because it was draining the battery faster than the needs of keeping the engine running. Didn't quite make it home but my towing insurance was able to get me the rest of the way since I was within 12 minutes from my brother's house.

If the car is not your primary transportation than going with a smaller battery may work out for you as long as you don't put any drain on the battery when the engine isn't running.

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0==WW==0
"…axles of evil…" - george w. bush

 

If you plan on having a huge system in your car I would go with the regular yellow top instead of the sport compact one. I had a yellow top and thing can handle anything.