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Hi all,
If an alternator was made to deliver 14.8v, will it affect/deteriorate/malfunction/destroy the P48 Instrumentation and functions?
An open debate. Hope to hear all reasons and suggestions.

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no I don't think it does as some of that voltage goes back to the battery

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14.8v is on the high side for a lead acid battery... I'd be more worried about overcharging the battery personally.

Where are you finding an alternator that fits a P38 engine with that set point?

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It would only possibly cause a problem if you tried to run from the alternator alone without a battery. 14.8V is OK with a high Calcium battery but would boil an older style Lead Acid one dry.

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Sloth wrote:

14.8v is on the high side for a lead acid battery... I'd be more worried about overcharging the battery personally.

Where are you finding an alternator that fits a P38 engine with that set point?

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lazbaz wrote:

Sloth wrote:

14.8v is on the high side for a lead acid battery... I'd be more worried about overcharging the battery personally.

Where are you finding an alternator that fits a P38 engine with that set point?. Others have fitted

I have Calcium battery that required 14.8 volts to fully charge it. Others have fitted VR-VW010 regulator but I am not sure it will fit on my Bosch alternator (4.6 Thor P38)

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No, you won't damage a Calcium battery if you charge at up to 14.8V but it still achieve full charge if you give it anything more than around 13.8V.

This https://www.ebay.co.uk/itm/14V-Bosch-Type-Alternator-Regulator-AUDI-BMW-FIAT-FORD-PORSCHE-SEAT-VW-VOLVO-/183895830413 looks to be the correct one for your alternator (but check the list to be sure).

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The electronics on most cars will certainly stand over 15 volts for a period of time - ie. the 12V regulators (as found in the various ECU modules etc) will be able to handle it OK: Some components, eg. incandescent bulbs, may 'give up the ghost' sooner of course.

Not quite sure why you would want to do this though lazbaz, is it because you think your calcium battery will not charge properly ? Again such batteries - basically lead acid with added calcium - might need to be trickle charged at 14.8V but that is not an 'operational requirement'. Typical alternator voltages are 13.8-14.4 and calcium batteries will work fine with that too.

There is a view that not providing Calcium batteries with a 'full 14.8 volts' however could shorten their lives to just a couple of years - due to sulphation and/or acid stratification issues. If you are concerned this is likely then just getting one with a 4-5 year warranty is a good idea of course......

Useful and very comprehensive resource on all this: https://batteryuniversity.com/