New Battery (Bosch Silver) - how important is the rating value?
04-18-2003, 07:53 AM
#1
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New Battery (Bosch Silver) - how important is the rating value?
Why is nothing straight forward?
I got a bosch silver from a local motor factors (£44) which I was told was correct for a 1990 M.Y. 911 - they ordered it specially. Its the right size with round posts, but the rating is 66 amp hours. I remember a recent post saying a 964 needs 74, and the owners handbook says 72. How vital is it that I get the right rating? I wanted to double check before I hook her up.
I got a bosch silver from a local motor factors (£44) which I was told was correct for a 1990 M.Y. 911 - they ordered it specially. Its the right size with round posts, but the rating is 66 amp hours. I remember a recent post saying a 964 needs 74, and the owners handbook says 72. How vital is it that I get the right rating? I wanted to double check before I hook her up.
04-18-2003, 09:04 AM
#2
Hi,
I have the same one - I assume your "local motor factor" is Halfords, and they list the 66Ah one as the correct fitment for 964s. Only after I got mine did I see all the posts saying it was too low.
I don't seem to have problems with mine - I get 30s or so of idle hunting when cold but I don't believe this is due to the battery. However - if I was you I'd be tempted to take it back and get a higher rating.
I have the same one - I assume your "local motor factor" is Halfords, and they list the 66Ah one as the correct fitment for 964s. Only after I got mine did I see all the posts saying it was too low.
I don't seem to have problems with mine - I get 30s or so of idle hunting when cold but I don't believe this is due to the battery. However - if I was you I'd be tempted to take it back and get a higher rating.
04-18-2003, 09:37 AM
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Dear Johnny,
The rating is very important. You might think that 66 is close enough to 72 but what it means is that you lack capacity to carry a load.
The 964 has a reputation of eating batteries. The reason for this is because its electrical load is very high. If you exceed the battery rating you will damage it. Summer months are not normally an issue but in winter when you are driving with headlights, heating, defrost fan runing, rear windos and outside mirror demisters, windshield and rear wipers and the stereo then the load can and will be very high. Porsche say a minimum for a reason. A 66 amp hour battery will work harder and last less time. A 66 amp hour battery will also supply less cranking or short term current.
Been there, done that, bought that t-shirt. Remember the only difference between a cab and coupe i the roof and Porsche say you need a 88 amp hour minimum for the cabs.
I can only as Dave suggests recommend you follow the minimum requirements and take it back and get the correct and recommended rating.
Ciao,
Adrian
911C4
The rating is very important. You might think that 66 is close enough to 72 but what it means is that you lack capacity to carry a load.
The 964 has a reputation of eating batteries. The reason for this is because its electrical load is very high. If you exceed the battery rating you will damage it. Summer months are not normally an issue but in winter when you are driving with headlights, heating, defrost fan runing, rear windos and outside mirror demisters, windshield and rear wipers and the stereo then the load can and will be very high. Porsche say a minimum for a reason. A 66 amp hour battery will work harder and last less time. A 66 amp hour battery will also supply less cranking or short term current.
Been there, done that, bought that t-shirt. Remember the only difference between a cab and coupe i the roof and Porsche say you need a 88 amp hour minimum for the cabs.
I can only as Dave suggests recommend you follow the minimum requirements and take it back and get the correct and recommended rating.
Ciao,
Adrian
911C4
