'91 928 Battery Spec
02-01-2003, 03:13 AM
#1
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'91 928 Battery Spec
What is the correct battery for a '91 S4?
When I bought the car almost 3 years ago, a reputable 928 shop in Southern California replaced the battery. I looked at it for the first time this weekend. To my big shock, it was completely lacking the clamps that are supposed to hold it in place!
Thank god it appears not to have broken or leaked, but it might be getting weak. When I start the car, the starter seems to have a harder time and the computer resets to average MPG most of the time - it didn't do this before. I checked the ground straps, cleaned the rear one on the trunk side - no change.
I want to make sure I buy the right size and type when it needs to be replaced. I haven't had the time, yet, to get the existing battery tested.
<img src="http://www.mossinger.com/928/928battery.jpg" alt=" - " />
When I bought the car almost 3 years ago, a reputable 928 shop in Southern California replaced the battery. I looked at it for the first time this weekend. To my big shock, it was completely lacking the clamps that are supposed to hold it in place!
Thank god it appears not to have broken or leaked, but it might be getting weak. When I start the car, the starter seems to have a harder time and the computer resets to average MPG most of the time - it didn't do this before. I checked the ground straps, cleaned the rear one on the trunk side - no change.
I want to make sure I buy the right size and type when it needs to be replaced. I haven't had the time, yet, to get the existing battery tested.
<img src="http://www.mossinger.com/928/928battery.jpg" alt=" - " />
02-01-2003, 04:56 AM
#2
Nichole,
Check the archives. Quite a few recommendations over a year ago.
I got the biggest Interstate Battery I could find.
If you can : buy a gallon of distilled water, and pop those caps -most no maintenance battery's have them- If you have an old turkey baster use it to top off the cells. Try not to overfill as you do need a little space for gas expansion, and keeping the level about 3/4ths of the way up the 'slots'prevents boil over. To see if you have been boiling over or there was prior spillage crawl under the rear end and look for powder at the vents in the battery box. Trickle charge for a day or two. Short trips are murder on the sHARk battery's.
HTH
John S. & Pattycakes
Check the archives. Quite a few recommendations over a year ago.
I got the biggest Interstate Battery I could find.
If you can : buy a gallon of distilled water, and pop those caps -most no maintenance battery's have them- If you have an old turkey baster use it to top off the cells. Try not to overfill as you do need a little space for gas expansion, and keeping the level about 3/4ths of the way up the 'slots'prevents boil over. To see if you have been boiling over or there was prior spillage crawl under the rear end and look for powder at the vents in the battery box. Trickle charge for a day or two. Short trips are murder on the sHARk battery's.
HTH
John S. & Pattycakes
02-01-2003, 09:16 AM
#3
Burning Brakes
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I believe Interstate was the most recommended battery. I am sure happy with mine. Here is the link.
<a href="http://www.ibsa.com/estore/view_product_detail.asp?mscssid=TGEB50SX34L19HBBD6VHP81SXC4T73P3&part_nu mber=MTP-91&category_id=0&find_spec=91&js=1" target="_blank">battery</a>
<a href="http://www.ibsa.com/estore/view_product_detail.asp?mscssid=TGEB50SX34L19HBBD6VHP81SXC4T73P3&part_nu mber=MTP-91&category_id=0&find_spec=91&js=1" target="_blank">battery</a>
02-01-2003, 05:50 PM
#4
Nicole,
Oops!
Forgot... Interstate Battery,
Model MTP-93
850 CCA
P.S. You probably know: When working with batteries, wether cell caps are off or not... ALWAYS wear eye protection.
If you can't run a hose to where you are working on battery at least have a bucket of clean water to rinse/flush acid off of you or car.
When working with that white battery corrosion ditrius don't breathe the dust - rinse mouth and nose, flush eyes and go wash up-. Baking soda works for corrossion clean-up and coke or other carbonated beverages will work in a pinch to neutralize acid.
HTH
John S. and Pattycakes. <img border="0" alt="[cheers]" title="" src="graemlins/beerchug.gif" />
Oops!
Forgot... Interstate Battery,
Model MTP-93
850 CCA
P.S. You probably know: When working with batteries, wether cell caps are off or not... ALWAYS wear eye protection.
If you can't run a hose to where you are working on battery at least have a bucket of clean water to rinse/flush acid off of you or car.
When working with that white battery corrosion ditrius don't breathe the dust - rinse mouth and nose, flush eyes and go wash up-. Baking soda works for corrossion clean-up and coke or other carbonated beverages will work in a pinch to neutralize acid.
HTH
John S. and Pattycakes. <img border="0" alt="[cheers]" title="" src="graemlins/beerchug.gif" />
02-01-2003, 06:35 PM
#5
Burning Brakes
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Hi Nicole,
If you need an inexpensive battery replacement, I have had excellent results with this one. This is not the factory specification. I am using it at my own risk. I could not quite bring myself to pay 3 times as much for the similar sized factory spec battery. However, I don’t have the upper tie down strap. The strap might still fit. I really don’t need the tie down strap. The battery fits really well down in its hole.
Battery 12 Volt
48/91-1: Part number
Brand: Autocraft Silver
Vendor: Advance Auto Parts
Cranking Amps: 870
Cold Cranking Amps: 700
Reserve Capacity: 120
As long as the battery is the right size, battery posts interface properly with cable connectors, tie downs interface well, cold cranking power is adequate, it is a 12 volt automotive type, I think the battery will work fine.
If anyone knows another criteria for a proper battery, I am curious to determine what else makes it right.
<img border="0" alt="[burnout]" title="" src="graemlins/burnout.gif" />
If you need an inexpensive battery replacement, I have had excellent results with this one. This is not the factory specification. I am using it at my own risk. I could not quite bring myself to pay 3 times as much for the similar sized factory spec battery. However, I don’t have the upper tie down strap. The strap might still fit. I really don’t need the tie down strap. The battery fits really well down in its hole.
Battery 12 Volt
48/91-1: Part number
Brand: Autocraft Silver
Vendor: Advance Auto Parts
Cranking Amps: 870
Cold Cranking Amps: 700
Reserve Capacity: 120
As long as the battery is the right size, battery posts interface properly with cable connectors, tie downs interface well, cold cranking power is adequate, it is a 12 volt automotive type, I think the battery will work fine.
If anyone knows another criteria for a proper battery, I am curious to determine what else makes it right.
<img border="0" alt="[burnout]" title="" src="graemlins/burnout.gif" />
02-01-2003, 07:36 PM
#6
Burning Brakes
Actually, there is no upper tie-down strap. There is a clamp with a bolt in the front and a wedge in the rear (or vis-versa). My GT has an Interstate MTP-91. YMMV.
02-01-2003, 07:59 PM
#7
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MTP is apparently what Interstate recommends. Now, I believe that Porsche offered a larger battery as an option - would that be the MTP-93? Would a regular alternator be able to fully charge a larger battery, or does a larger batttery also require a different alternator?
I called the nearest Interstate dealer, and they don't have the MTP-91 in stock. But first I'd have to have the old battery checked. Hopefully it's only the battery that's going bad...
I called the nearest Interstate dealer, and they don't have the MTP-91 in stock. But first I'd have to have the old battery checked. Hopefully it's only the battery that's going bad...
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02-01-2003, 08:13 PM
#8
Burning Brakes
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Nicole,
You can go to probably any major chain auto parts store, and have the battery and alternator checked in about 10 minutes. They can also check their computer, and give you listings for battery specifications. Most of these guys will do all the above and battery installation for free.
<img border="0" alt="[burnout]" title="" src="graemlins/burnout.gif" />
You can go to probably any major chain auto parts store, and have the battery and alternator checked in about 10 minutes. They can also check their computer, and give you listings for battery specifications. Most of these guys will do all the above and battery installation for free.
<img border="0" alt="[burnout]" title="" src="graemlins/burnout.gif" />
02-01-2003, 09:49 PM
#9
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Just to state the obvious: Always disconnect the battery before doing any thing to it. And when doing so disconnect the negative side first.
Many years ago, I had an explosive problem when my hot ratchet touched the grounded body. Of course, that was my Austin Healey with positive earth - but the PRINCIPLE is the same!
Just call me Sparky.
Many years ago, I had an explosive problem when my hot ratchet touched the grounded body. Of course, that was my Austin Healey with positive earth - but the PRINCIPLE is the same!
Just call me Sparky.
02-02-2003, 01:14 AM
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Nicole
I've got a Duralast Battery in the garage ready to be installed. If you need it I'll sell it cheap. I bought it along with the interior and EuroS motor out of a parts car. The battery was only in that car for about a month. It looks brand new and has a 7 yr prorated warranty. I have no use for it and it's just taking up space in my garage. BTW, I've stored it off the ground so it should be good to go. I can ship it (can you ship a battery?) to you and it's a direct fit. I'm assuming all model years take the same battery. Let me know if you want pics or if you're even interested.
I've got a Duralast Battery in the garage ready to be installed. If you need it I'll sell it cheap. I bought it along with the interior and EuroS motor out of a parts car. The battery was only in that car for about a month. It looks brand new and has a 7 yr prorated warranty. I have no use for it and it's just taking up space in my garage. BTW, I've stored it off the ground so it should be good to go. I can ship it (can you ship a battery?) to you and it's a direct fit. I'm assuming all model years take the same battery. Let me know if you want pics or if you're even interested.
02-02-2003, 01:25 AM
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Burning Brakes
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Nicole, the 91 battery I have and that Ed also recommends is the highest rated Interstate for the 928. The 93 is physically larger and will not fit in the battery location. I already checked this out and you can also check the dimensions on their web site.
I picked mine up at Discount tire. It was the only one they had and they guy asked if I had some kind of exotic car since they never sell them
.
Then I actually installed it in their parking lot - amazing how the tool kit has all the right tools - and left them the old one.
I picked mine up at Discount tire. It was the only one they had and they guy asked if I had some kind of exotic car since they never sell them
.Then I actually installed it in their parking lot - amazing how the tool kit has all the right tools - and left them the old one.
02-02-2003, 01:34 AM
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Just another note, I got my Interstate at Kragen. In stock, and relatively affordable.
I was intrigued by the Interstate Optima battery: <a href="http://www.ajusa.com/cgi-bin/inventory/view_product?prod_id=0000000188&part_number=AJR%20611%20800%20U" target="_blank">AJ-USA </a> I like the zero leakage idea.
No matter what you get, make a photo copy of your receipt. My original receipt was printed on thermal paper, and is now plain white!
I was intrigued by the Interstate Optima battery: <a href="http://www.ajusa.com/cgi-bin/inventory/view_product?prod_id=0000000188&part_number=AJR%20611%20800%20U" target="_blank">AJ-USA </a> I like the zero leakage idea.
No matter what you get, make a photo copy of your receipt. My original receipt was printed on thermal paper, and is now plain white!
02-02-2003, 01:51 AM
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You could also head on down to Sam's Club and get a Champion size 49, 1000 cranking amps@32F, 850 CCA. This is a BIG battery and you should definately have a bowl of Wheaties before installing. I don't know if the battery tray size changed from '82 but the Champion just fit in mine. It was under $100. So long as your alternator can deliver at least 13.5 Volts to your battery (measured across the battery terminals with a hand held volt meter, engine running with a few accessories on) it will charge any battery. Good luck!
02-02-2003, 03:13 AM
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Jerry:
Did the tire place also test your old battery, or were you already sure you needed a new one?
4MIDLIF:
This new type battery sounds intriguing. I wonder, if anybody has tried it, and can confirm that it lives up to the advertised claims. I'd be willing to pay $40.00 extra for a battery that lasts 2-3 times as long...
Did the tire place also test your old battery, or were you already sure you needed a new one?
4MIDLIF:
This new type battery sounds intriguing. I wonder, if anybody has tried it, and can confirm that it lives up to the advertised claims. I'd be willing to pay $40.00 extra for a battery that lasts 2-3 times as long...
02-02-2003, 04:48 AM
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Since I started looking, I have found other sources and more info on these batteries. They are, of course, available on eBay, at the lowest prices I've found so far.
<a href="http://www.optimabatterystore.com" target="_blank">www.optimabatterystore.com</a>
<a href="http://www.optimabatteries.com/" target="_blank">www.optimabatteries.com</a>
<a href="http://www.todobaterias.com/archivos/optima-bateries.pdf" target="_blank">Battery Specs and info</a>
<a href="http://search.ebay.com/search/search.dll?MfcISAPICommand=GetResult&ht=1&SortProperty=MetaEndSort&query =optima+battery" target="_blank">eBay search</a>
Looks like the 800S is the appropriate unit and one can be had for about $120.00 delivered.
I'm ging to check the dimensions and mounting possibilities sometime Sunday. I just might get one of these.
<a href="http://www.optimabatterystore.com" target="_blank">www.optimabatterystore.com</a>
<a href="http://www.optimabatteries.com/" target="_blank">www.optimabatteries.com</a>
<a href="http://www.todobaterias.com/archivos/optima-bateries.pdf" target="_blank">Battery Specs and info</a>
<a href="http://search.ebay.com/search/search.dll?MfcISAPICommand=GetResult&ht=1&SortProperty=MetaEndSort&query =optima+battery" target="_blank">eBay search</a>
Looks like the 800S is the appropriate unit and one can be had for about $120.00 delivered.
I'm ging to check the dimensions and mounting possibilities sometime Sunday. I just might get one of these.