Optima Batteries. Which model applies to a 74 2002

[Guest Anonymous]

with a 320 alternator. There web site says no match for a BMW 320i (nothing older referenced). It is hard to believe that there isn't one that works.

[Guest Anonymous]

(nt)

[Guest Anonymous]

all the cars( 2002s, 320i, etc) are too old for application compatiblilty and fitment wiht 99% of the wesites out there.By adding a "320i"- I bet the computer thought it needed to tell you if an Optima fits into a 320i OEM battery location. No way the Optima site or most any site)is going to know that information.If you were trying to find out if the Optima red is compatable with a 320i alternator: it is. Running a 320 alternator is fine- in fact, most 2002s are upgraded to one at some point. Actually,the battery does not care what type alternator you have - as long as it puts out 12 volts( at least: more like 12.3 sitting) and puts out a minumum of x amps/watts power( old race engines used to have little alternators that made 6-10 amps and those are probably insufficient to charge a modern battery). Optima makes 3 sizes Red top batteries. I know this due to the tireless efforts of a previous post from a Board member who researched the devil out of this subject. You say you have a 1974 2002. I presume you want to mount the Optima Red Top in the OEM battery location. You can obtain that dimension from the BMW parts fiche/CD- but it will probably just give you tray dimensions. That will be insuficient for your needs. You need the volume as well- how tall/wide,etc. Best bet is to go to your car and take a measuring tape( cloth is best for this) and measure your 3 dimensional battery storage area, including any parts that intrude into the area( brake master comes to mind in the round lights). Then go to Costo or some other big box /big discount Optima supplier and measure the battery they have on the shelf. My Costco has the standard Optima Red, Yellow,and Blue top batteries for sale every day of the year at $100. Normal price is about $125- I bought my Red Top from an expensive retail outfit/ stereo install place down the street for 125 bucks. If you anticipate problems because of OEM dimensions, see if you can make the Optima work utilizing the side terminals if it is too much trouble to hook it up conventionally. You can place the Optima on its side, if necessary. Referring again to the seminal post,info about Optima Red batteries and the 3 sizes of them, and the way to install under the rear seat,on its side. There is also info in that post about Hawk racing batteries, that are even smaller,and that are one step "better" than Optima- they use them in race cars and in jet aircraft and other high preformance/weird placement machines. They do not have much amperage holding capacity, due to their size. But they will start an engine and keep mimimal systems running.OR,and probably your easiest alternative for OEM location, Interstate is a common BMW replacment battery in most BMW cars, sold by most BMW repair facilities. In fact, my Sahara had an Interstate battery when I had the battery in the OEM location. I went to Red Optima when i put my battery in the trunk. You should be able to find what you want, first from that post and the resulting thread, and then through race suppliers websites , like Summit, Pegasus, etc. They handle all the variants in car batteries. You may be able to get amn OEM location match, other than a BMW battery, from a BMW aftermarket distributor like Worldpak or SSF. They can get the correct sized battery for your 1974 OEM location in a heartbeat. Or, talk to BMW dealer parts department and find out what they charge fior the correct OEM replacement battery. You will waste your time, unfortunatley, with the Optima website, unless they have improved its information content recently. Good luck. Use the search functions for FAQ and for Roadfly to find that historic post about battery types and placement. Maybe the author is on the Board now and can help you. It was a wonderful piece.