dynalite alternators

[ctpearce]

I'm thinking of fitting a dynalite alternator to my Aceca Bristol as the dynamo is scarcely adequate for more powerful headlamp bulbs, electric fan, wipers plus the ipad running a timer function etc.
   I'm worried about the downsides of the extra current though - has anyone any experience of this and is the higher amperage (45 vs 25amps) a problem eg will it damage the ammeter or require higher spec. cable to take the extra current?

[rsk289]

You should be able to calculate what the total power draw could be at its most extreme - e.g. headlamp circuit total, wipers maybe, heater, 200W stereo etc.
   Watts=Volts x Amps, and you know it's going to be around 12V, so do the sums and you'll get a ballpark figure for current.  The alternator will only put out what's asked of it - but if you get a short or fault, and it's a 45A output, it can give that much more than a 25A generator.
   Hidden fuse/circuit breaker/fusible link, maybe?

[paho]

As far as I know you cannot do a straight swap alternator/dynamo. Alternators normally contain their own regulators, so the dynamo´s regulator /Control box has to be removed (requires strapping the wiring) or replaced with a dummy box.
   Dummy boxes have the advantage of replacing the regulator without having to strap the existing wiring, some dummy boxes also come with a main fuse fitted. There is nothing to stop you fitting a 25A fuse to protect the existing wiring as an alternative. If you find you need more Amps replace the main cable. I would review the rest of the wiring loom and fuses too if you are adding lots of extra electrical goodies.
   
   There is lots of info and advice from manufactures and suppliers on how to do this type of conversion on the www. Good luck /Paho

[Jam2]

Have you considered reducing the 'night' power consumption by fitting LED bulbs in sidelights, instrument lights etc.,  there are LED headlight bulbs about too, but I'm not sure if there is anything suitable for the Aceca.  One could fit a larger capacity battery and unless you are doing 10hr night drives with the electric fan running as well all should be fine.  This route might save a few problems in altering from the standard dymano set up.

[David Byng]

I found my Aceca-Bristol headlamps to be as effective as a Toc-H lamp! D S advised fitting a Dynalite Alternator and Wipac halogen headlights.
   I bought a Dynalite C39 replacement (this has the lugs 144mm apart) and Wipac headlights and I'm assured that the result is good. There is an alternative alternator comp. called WOSP. I was assured that this company's product is also excellent.
   When BE601 is returned to me, I look forward to being able to go out in the dark.

[B.P.Bird]

David,
   You have made my day - 'dim as a Toc-H lamp' wonderful to hear that again and an apposite description of Thames Ditton electrics as the saying is nearly as old as the car maker.
   By the bye I have followed this discussion with a wry smile: There is no need to worry about whether or no your loom will stand a 40 amp alternator instead of a 24 or 28 amp dynamo when the very same loom is hooked up to a lead acid battery which will supply 500 amps given half a chance. This kind of current produces instant smoke and red hot wiring. A driver controlled Battery Master Switch and a Fire Extinguisher are essential regardless of the generator type.
   In my experience dim headlamps mostly come from a poor earth at the headlamp bowl and changing bulbs or fitting alternators will not make much difference. There is no point in going down the alternator route til you have done the arithmetic described by Roger King in his post of 28th October: If all the electrics add up to more than the generator system can supply then your night time journey will become progressively darker. Taken to the extreme the battery will be exhausted. On the other hand if the sum total of electrical load is 23 amps and the dynamo is producing 24 amps then you can go forever

[ctpearce]

Many thanks guys for all the comments.
   I did check on the power usage of the various bits and pieces, using the ammeter which, of course, only measures the current flowing into or out of the battery; these are approximate as I'm not sure how accurate it is, particularly at higher currents, as I've never seen over 15/20 amps in either direction in actual use:-
   -side and headlights (full beam 65w) 10amps
   -brake lights                        3amps
   -fan                                 6
   -heater                              3
   -wipers                              3
   ie 25amps or so in total so it's no surprise that the dynamo struggles on occasions in the wet and traffic etc. (plus charging the ipad on the Mille Miglia).
   So, I've converted to negative earth (not strictly necessary) bought the Dynalite and will give it a go. If the ammeter keeps bouncing off the 30amp end stop or the wiring starts sizzling I'll clearly have to have another think.
   A connected question; Holdens advise the best headlights are a Wipac or Cibie H4 unit with halogen bulbs (ie not my present Lucas 'tripods' plus BPF halogens) - does anyone have any experience of these?