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Will there be any problems running a 45A alt on a 1.2 16v cinq? I'm going to strip it down to the bare essentials anyway & if I do have any audio it'll just be a headunit with the in-dash speakers.
Technical Which alt for a 1.2 16v? 45A or 60A?
- Thread starter GoBe
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Technical Which alt for a 1.2 16v? 45A or 60A?
Why would you want to?
OHC one is said to be 65amp, OHV one 55amp.
OHC one is said to be 65amp, OHV one 55amp.
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Firstly surely that's 2(45+5) = 100W = 8.3A @ 12v
The alt on the Sei is associated with the engine in the car (which came out of a Cinq), it was replaced 9 months and less than 3000 miles ago. The 60A one from the other engine may be 82'000 miles old and while spins freely feels slightly rough when turning by hand. Finally as this is my track car wouldn't the 45A one be slightly lighter on the engine at any given draw?
The alt on the Sei is associated with the engine in the car (which came out of a Cinq), it was replaced 9 months and less than 3000 miles ago. The 60A one from the other engine may be 82'000 miles old and while spins freely feels slightly rough when turning by hand. Finally as this is my track car wouldn't the 45A one be slightly lighter on the engine at any given draw?
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I can't do the maths!
I think you'd be OK with either providing you don't spend too much time in traffic at night and the battery is OK.
Having said that, I don't know what the draw of the other systems -- apart from the lighting -- is and I don't know at what revs the alternator produces full output.
I think you'd be OK with either providing you don't spend too much time in traffic at night and the battery is OK.
Having said that, I don't know what the draw of the other systems -- apart from the lighting -- is and I don't know at what revs the alternator produces full output.
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Well with all the lights on which I have bulb ratings for I get 42A BUT that's having main + dipped beam on at the same time and all the indicators, well that's 17A of current that in reality isn't going to be drawn most of the time. I think there's enough headroom there, also I'm likely to buy a rather large batter that'll be mounted in the boot which will help things.
So I'll grab the 45A alt, buy an ammeter and play it by ear.
So I'll grab the 45A alt, buy an ammeter and play it by ear.
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If it's purely track car, then fit HID to reduce power draw hugely. Alternatively, run without an alternator, just keep it on charge 
Looking at my car:
ECU draws about 800mA
Coil draws 10A
Injectors 1A maximum Id guestimate at 100% duty cycle
lights draw?? You appear to know that already
I think you will be fine with the 45A but i don't see it making much difference tbh.
Or retrofit a fancy clutched alternator like the new mini's etc. No load when they don't need to charge Not sure how they work exactly though
I'll check my multimeter and see what it can handle, then run my car and see what it pulls if its safe to do so.
Kristian
Kristian
Looking at my car:
ECU draws about 800mA
Coil draws 10A
Injectors 1A maximum Id guestimate at 100% duty cycle
lights draw?? You appear to know that already
I think you will be fine with the 45A but i don't see it making much difference tbh.
Or retrofit a fancy clutched alternator like the new mini's etc. No load when they don't need to charge
Not sure how they work exactly though I'll check my multimeter and see what it can handle, then run my car and see what it pulls if its safe to do so.
Kristian
Kristian
Nominal current with lights on should be between 20/30 Amps. It's things like power steering (20Amp?), Heater motor (5Amp?) and cooling fan (5Amp?) that use the current. There won't be much weight saving between 45 and 60 Amp. They do a 55Amp. The alternator only adds load when you use alot of power or the battery is cooked.
Wouldn't fit HID as they are illegal to cars not fitted with them as standard iirc
Personally I would fork out the extra on getting the one with the engine recon'd just for piece of mind As what's 70quid against the hassle of having to change it in a few months
Personally I would fork out the extra on getting the one with the engine recon'd just for piece of mind
As what's 70quid against the hassle of having to change it in a few months - Joined
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cc1, but would it have less loading fora given electrical output?
jamie, engine will have to come out at least 2 times anyway so taking the alt off isn't any extra hassle!
jamie, engine will have to come out at least 2 times anyway so taking the alt off isn't any extra hassle!
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The more power you use, the more load on the alternator.
Add up the current values of all things that will be used and add 10Amps for charging.
The battery is there to start the car mainly, so the alternator will supply all power as required.
The only reason for having such a large battery is for the amps required for starting.
Incidentally, some 1.5 volt batteries like the HP2 type are capable of supplying over 100 Amps when in short curcuit.
Add up the current values of all things that will be used and add 10Amps for charging.
The battery is there to start the car mainly, so the alternator will supply all power as required.
The only reason for having such a large battery is for the amps required for starting.
Incidentally, some 1.5 volt batteries like the HP2 type are capable of supplying over 100 Amps when in short curcuit.
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