Originally Posted By: HTSS_TR
Originally Posted By: SavagePatch
I don't see how it does much to help but I will take your advice and leave it in place anyways.
Originally Posted By: horse123
The battery will heat up with a thin layer of foam within minutes of the time it would heat up without it. You don't need it.
Funny, people in here will defend a catch can to death even though manufacturers don't include it because it CLEARLY DOES NOTHING. However when it's an unnecessary part that's already in there "you'll probably cause a nuclear explosion if you remove it"
Very simple test with an infrared heat gun: with heat gun check the temperature on the side of the battery after normal driving of around 15-20 miles, one with cover(quickly remove cover to check the temp) and one without cover.
The temperature on the battery with cover should be about 15-20F lower, more on a hot afternoon drive and especially after a long drive of 25-30 miles or longer.
Battery lasted longer in cooler climate, some manufactures have 2 types: standard and hot climate. Batteries in warmer area such as Florida, Texas, Arizona, Nevada, So Cal ... didn't lasted as long as in Northern states.
After the battery heats up to engine bay temp (which it will on any drive 30+ minutes regardless of insulation), all the insulation is going to do is keep the heat in after the car is off and kill the battery faster.