My crossflow needs a bigger alternator

[Anonymous]

I have a cortina running a Crossflow with a stock Cortina 55A alternator and standard pressed steel bracket.

I noticed the newer XF falcons etc had a different bracket and alternator setup. Are any of these bigger than the 55A one I have now?

Doe anyone know of a simple conversion to a bigger unit of any sort.

Currently EFI, Thermo fans and headlights are enough to have my battery voltage at 11.5V with the engine running.

 

[Anonymous]

Mark I had a similar problem with mine when I ran injection my standard Altenator was only a 35A though. Grab a V6 Commodore Alternator 120A I think. Remove the front housing and fit the falcon one should bolt up with the standard bracket and give you heaps of power.

 

[aussie7mains]

If the alternator will bolt up, the problem will be that the single belt sheeve wont drive any more than about 55a anyway, you need two or the poly vee to get more, I tried!
Even with much more belt wrap by a jockey pulley on the back of the belt, I couldnt get above 55a without belt slipage.
A7M

 

[xctasy]

aussie7mains is bang on. I'd suggest looking at a gilmer belt drive set up if costs permit. JD posted one in the Hot Six Triple Carb post. The bigger the amps, the more HP sucked up. I like modern serpentine drives, but there's no point unless your Cortina is power steered, Air conditioned, and you have bulk time to fit an OHC six set up on.

Belt driven upgrades make the quietest people swear, but it beats getting stranded with some smart a$$ telling you your Cortina is UFO-afflicted!

 

[Anonymous]

the XF has 3 different types of alternators:
40A - non air conditioned models
50A - air conditioned models
60A - EFI models

you could easily chase up a 60 amp alterantor from a wreckers pretty cheaply i reckon and give that a go.

 

[Anonymous]

Mark,
I am going against the flow here. Run your car around to a trustable auto electrician and get all the electrical system checked.
What you have listed shouldnt draw anywhere near 55a.
A weak 35/55/60 amp altenator is a problem whatever the rating it is.
Noel

 

[Anonymous]

okay thanks for the suggestions guys!

I like the sound of this V6 commodore idea but the belt slippage thing has got me worried. I already threw a belt once before while it was on the dyno.

As for why my car needs so much power I don't quite know. I only really have a problem when the thermo fans are on and this is usually only at idle. They are an older style davies Craig one and they are crap and I think they draw way more current than the newer ones. They don't even cool the engine all that quickly and I want to get rid of them. Only problem is all the ones i have seen have a bigger shroud and don't fit in.

I think the alternator I have now is also getting a bit tired.

 

[MADXF]

I had been having some troubles with my alternator as well.

I have an XF EFI and from the service manual it is supposed to have a 55amp alt. I found a 60amp we had at home and threw it in and now when the voltage drops real low (just after startup with the rear demist on) it slips. Once the volts are up to normal there is no slippage though.

If you put in a 120amp alt, what other things would you have to change wiring wise?

 

[aussie7mains]

Alternators are only about 50% efficient, thus to get 120a you need:
120X13,8/0.5=3312w, thats 3.3 Kw one vee belt on a 50mm pulley wouldnt even look at that. You need a poly vee or toothed belt to drive it.
have a look at a Ef/L they have 105a output, the cable from the alternator is qite big, and it needs to be to carry that sort of current.
The DC fans draw about 10a when running, but qite a bit more to start up, and dont forget you need to keep system voltage about 13.2v to charge the battery.
A7M

 

[Anonymous]

Something to think of guys,
If the altenator is functioning correctly and is not supplying enough power no matter what is done.
Twin altenators is an option.
This was quite common on the early/F100 ambulances, but I dunno what would be harder. Converting to twin altenators or change to a multi vee drive belt for a 120 A altenator.
Noel.

 

[addo]

I'd forgotten 'bout that. The '73 F100 shared with a mate had dual battery trays... and a Clevo in place of the 300. :roll: