[Ron Stygar]

Lately, the batteries that come with the BMW's I purchase are not that good. The one in my '97 318ti failed in a little over two years. BMW warranty on batteries is two years.
The battery in my '01 M coupe never had any reserve capacity. Leave something on for a short time and you come back to a car that won't start.
There is an article in the May '02 BMWCCA Roundel discussing the same problems. The batteries are made by DBMC of Winston-Salem according to the Roundel article.

http://www.ibsa.com/www_2001/content/products/ratings.asp

http://www.batterycouncil.org/

In my ti, I replaced the battery with an Interstate
MTP-91. I have also used the same battery in a friends car.

http://www.interstatebatteries.com/

As one less thing to worry about and for more reserve capacity, I decided to replace my less then one year old battery with the MTP-91 Interstate one. The Interstate MTP-91 is the same physical size as the BMW group 48 one in the coupe. The Interstate one has better ratings. It also has a 6 year pro rated warranty. It cost me $92.00 and weighs 9 pounds less than the BMW one (36 versus 45). It comes with a vent kit that interfaces to a smaller hose like the BMW uses. The BMW hose is too short. I replaced the 10 inch BMW hose with a 12 inch one. I also had to remove, using a razor knife, a small area of the foam spacer piece to accommodate the hose relocation. The following pics show the before and after.

When disconnecting a battery, remove the ground lead first. That way when removing the plus lead, and your wrench goes to body ground, no sparks.
When reconnecting, install the plus lead first for the same reason.

 

[Steve Borsse]

Ron you're jumping around like a "bunny" from upgrade to upgrade. They're all great stuff of course, but we sittin here kind of wiating for your Part 2 of "Let's gear this Mthhher down with 3.46 gears. and polish down our skins.!

 

[Randy Forbes]

Ron,

Are the Coupe and Rdstr batteries the same?
My guess is that they are.
Have you looked at both yours and Al's to compare them?

I too have heard that the oem batteries aren't that good, and now the black car is over three years old.

I have used plenty of Interstate Batteries in my old British cars, and you know what the electrical systems in those are like...

 

[Ron Stygar]

Ron you're jumping around like a "bunny" from upgrade to upgrade. They're all great stuff of course, but we sittin here kind of wiating for your Part 2 of "Let's gear this Mthhher down with 3.46 gears. and polish down our skins.!

Trying to get my car done. Many drives coming up soon.
Have many how to's on the to do list. Will get to them eventually if I keep waking up.

 

[Ron Stygar]

Ron,

Are the Coupe and Rdstr batteries the same?
My guess is that they are.

>>>I agree. According to parts data they are.

Have you looked at both yours and Al's to compare them?

>>>Nope.

If you want to stick with the BMW vent hose 61 21 1 377 745 gets you one meter of it for $2.35 retail. Enough to do three cars.

 

[Ron Stygar]

Whoops. Forgot the manufactured date code stuff

Interstate uses a two character date code.
First character equals the month.
Second character equals the year.
This info is stamped into the battery case.
On the one that I purchased, E2...
E2 equals May '02.

 

[DaveM]

What about Optiima batteries?

Hello, Ron.
Was wondering if you ever considered Optima batteries in place of the Interstate. I have these in my truck, quite nice.

I will have to do my battery one day soon, so was quite interested in your post!

dave

 

[Ron Stygar]

Re: What about Optiima batteries?

Hello, Ron.
Was wondering if you ever considered Optima batteries in place of the Interstate. I have these in my truck, quite nice.

I will have to do my battery one day soon, so was quite interested in your post!

dave

Not really. I looked at them in a store and they didn't look that easy to mount. Not sure if they like vibration or not.
Shawn McCurdy has one in her '00 M coupe. With the top cover left off, it fit fine.

 

[Shawn Fogg]

Ron,

Any concerns regarding the charging system and the battery?

Shawn

 

[Ron Stygar]

Ron,

Any concerns regarding the charging system and the battery?

Shawn

Not yet. I have had one in my '97 318ti since '99. Last Fall I installed the second one in Rosemarie's '84 528. I also replaced the group 48 one with a group 49 in my '86 325is.

 

[///M-Bark]

Re: What about Optiima batteries?

Hello, Ron.
Was wondering if you ever considered Optima batteries in place of the Interstate. I have these in my truck, quite nice.

I will have to do my battery one day soon, so was quite interested in your post!

dave

Like Ron said, I used an Optima in my coupe. I wanted a completely sealed battery because on more than one occasion the stock battery barfed out battery water onto my garage floor. Luckily there was no spillage onto any painted surfaces. Other coupe owners have had the battery barf while they were driving and it ruined the paint on the back end of their cars.

 

[Shawn Fogg]

Ron,

Thanks, good to know they are working for you. Mine is coming up on 6 years so I will probably be replacing it fairly soon.

Shawn,

Did you use the 8002-002 (red top) or 8003-151 (orange top with reverse connectors) Optima?

Shawn

 

[DaveM]

how to Optimize the Z3

Shawn:

Any special tricks or work you had to do to fit the optima battery?
Seems like it might be a little big for the battery well.

thanks
dave

 

[///M-Bark]

Ron,

Thanks, good to know they are working for you. Mine is coming up on 6 years so I will probably be replacing it fairly soon.

Shawn,

Did you use the 8002-002 (red top) or 8003-151 (orange top with reverse connectors) Optima?

Shawn

I used the orange top. One cable was still too short and had to be extended just a little.

 

[///M-Bark]

Re: how to Optimize the Z3

Shawn:

Any special tricks or work you had to do to fit the optima battery?
Seems like it might be a little big for the battery well.

thanks
dave

The Optima is taller but less in width and length. I had some of that expanded foam packing from an unrelated shipment and I cut some pieces of it to fit into the voids around the battery and shoved them in, just to keep it from shifting around. The black plastic cover that goes over the stock battery wouldn't fit back over the Optima so I just left it off. The hatch floor fits over it that way just fine.

 

[ARC///M]

:bigpimp: This is what i WILL LOOK LIKE WHEN I fly by FLY BMW.WITH THE NEW BATTERY INSTALL.!

 

[scottn2retro]

Bump . . .

just in case anyone is looking into replacing a battery anytime soon.

 

[Dan Wang]

I did the exact battery upgrade when in my 95 M3. My battery came with the hose vents.

Excellent battery so far.

 

[caylan]

Thanks Scott! Re: Bump . . .

just in case anyone is looking into replacing a battery anytime soon.

it's a nice cool 20 degrees in the NationsCapital.
Last night it was in sigle digits.
The garage is not heated (thoug insulated).

This really helps.:thumbup:

 

[caylan]

Question about release hose for RonS.

http://www.interstatebatteries.com/

It comes with a vent kit that interfaces to a smaller hose like the BMW uses. The BMW hose is too short. I replaced the 10 inch BMW hose with a 12 inch one. I also had to remove, using a razor knife, a small area of the foam spacer piece to accommodate the hose relocation.

Ron, I connected the original BMW hose from the OEM battery to the hose that the store gave me for the MTP-91.

I stuck the end of the BMW hose through the hole underneath the bottom of the battery. It's sticking about 2 inches out the bottom of the coupe.

Is this the correct method?

Thanks for any insights.