BRAM

iTrader: (1)

As above how how many volts are you getting at your batt when your car is idleing?

On a S2 2.1zvh we are getting 13.5 volts when we have a new standard rs turbo alternator on but we thought this was not high enough so we ran a new wire from the alternator to battery but this didnt make any difference.

We then changed the alternator again with the one off my cosworth and modified the bracket to make it fit and now we are getting 14v but think we should see a few more than that.

Any ideas what we can try next?

Cheers Bram

steviesnutz

why would you want more than 14 volts gees , your car runs a 12 volt system , , , a bit more to charge and run ancillaries , job done ? why are you looking for more ?

Glenn_

iTrader: (1)

14 volts is good when the engine is running.

st3v3

ermm are you for real??

If you had your headlights, wipers, front screen fan on, maybe your radio at the same time and not giving out the correct charge, how long do you think you'd last with the winter nights??

BRAM

iTrader: (1)

It was 14v at idle with everything switched off but when we got things switched on the voltage drops and the car has got twin fans on so when they kick in it drops again.

We just dont want the voltage to drop when we are driving and then loose power to the fuel pump and would like to get it sorted before the car goes to get mapped

botters

iTrader: (2)

13.5-14 volts at idle with heavy loads will be fine mate with rpm increase the voltage will increase ever so slightly as well

steviesnutz

ok so 14.4 volts if you strive for the best , but you got to consider peukertert's law and no thats not a wind up , , , ,

bassboy

In the audio world we thrive for more/stable voltage

Have you checked what the output is directly at the alt? Is it higher than it is at the battery?

I would keep a 4g run of power cable from alt direct to battery, and ADD a 4g earth from battery to chassis, engine to chassis and possibly alt to chassis

When I upgraded the above cabling (known as the big three), my voltages went up from 14v to 14.5v but I used 0g cabling throughout as its a big sound system, but for you, 4g will be more than fine! The other thing I noticed is the voltages were more stable, AND they would recover quicker, say for example I was booming away, and saw voltage of 12v, they would shoot back up to 14.4v within 10seconds whereas before they took a good while to recover!

bassboy

Psycho Warren

iTrader: (5)

14V on idle is fine.

if your replacing the alternator to battery and battery to car positive cables make sure you replace the earth straps too. They are both as important as each other.

anything 13.5V or more on idle is fine. as said, its on load thats more important. as long as it holds 13.5V or more under load is fine as you still want to ensure its charging despite load. On load voltage is more important.

Otherwise do a lot of night driving in winter and youll soon find a flat battery!

BRAM

iTrader: (1)

Thanks for all the replys everyone some good info so 14v at the batt should be ok just need to make sure that we are getting the same at the ecu and pump.