It is interesting to hear this discussion about VSCC and alternators potentially being OK as long as not too conspicuous.
As many folk on here must have done, an alternator conversion is/was common DIY mod for those of us that run/ran BMC/BLMC/BL A Series engined cars of the late 1950s to early 1970s that were 12V dynamo equipped, such as MG Midgets, Austin Healey Sprites, Austin A35, Morris Minors and Minis.
This was primarily a way to keep going or improve everyday transport budget secondhand cars - such as my rusty 850 Mini and 850 Mini van in the 1980s. This had the advantage of not having to pick which two electrical items from the menu to use on a wet, cold night - wipers and lights, but no heater/‘de-mister’ (re-distributor of interior fug) (as for your home installed radio - nae chance to keep you company on a long journey). Scrap cars were a source of Lucas alternators (and if unlucky you had a core one to use for an exchange rebuilt item) and alternator plugs, as well as splashing out for a new alternator at Lucas depots or Minispares Centre etc and the conversion to negative earth done at the same time; quality issues with replacement voltage regulators was a factor too (and still is) as is lack of folk who have the knowledge and skills to adjust /service/ repair them (rather than me who ineffectually, ignorantly and incompetently fiddled with voltage regulators in the dark using a Haynes car manual).
Now as an owner of a 1961 Austin Healey Sprite MkII for fun, not everyday transport, I have got it charging its battery properly by having the original Lucas C39 dynamo rebuilt and obtaining a genuine Lucas voltage regulator that has been properly checked/serviced (thanks Dr John E Davies for sorting these along with my rev counter gearbox). It also allows my original rev counter to work as it is driven off the rear of the dynamo through a tiny reduction gearbox. Without such help until recently I would have just switched to a Lucas alternator and change the car from positive earth to negative earth and had to fit a later electrically powered rev counter (not with the correct lovely Healey style face) to replace my cable driven one. An expensive alternative these days are the alternators that externally look like Lucas dynamos - e.g. Dynamators - including the option of one with the rev counter take off.
Another modern option for my case is the availability of small lightweight Japanese alternators by Denso. This is a tempting, if not period-ish looking at all, instead of worrying about the quality now of recently produced ‘Lucas’ alternators.
Enough rambling. But it highlights how options change with time and how cost, desirability and availability of mods change as well as one’s circumstances, transport requirements and perspective.
If we go back to the thoughts of impecunious enthusiasts of the 1950s-1980s, people would fit what was available at that time that could meet their needs in terms of availability and cost of a replacement components/conversion, skill and tools and a place to fit it, and if there was any choice what additional advantage it offered beyond whether they could afford/obtain/fit it. Noting when this was someone’s only mode of transport, rather than an additional leisure vehicle, then it had to be got mobile again quickly and economically, often fixed in the street with a few tools. If Denso alternators were available and cheap in the 1980s my Minis would have had them as a quality good value upgrade to improve reliability and useability, my Sprite will stay with positive earth and a dynamo until I face a problem I cannot fix with the dynamo and voltage regulator - if that happens will be a Dynamator conversion if I can stretch to the extra expense, if not a good Lucas alternator (if one can be found) and accept the loss of rev counter drive and use of a very obviously wrong looking rev counter gauge. I note you can now even buy again positive earth ‘Lucas’ dynamos as well as positive earth ‘Dynamators’, but not sure why anyone would bother with either conversion as positive earth - why not switch to neg earth at the same time (and neg earth dynamos and Dynamators more readily available and wider choice).
It is interesting to see what the 750 Motor Club Historic Formula 750 racers count as in period mods (I do understand that VSCC are thinking of a different period and H750 Formula includes Reliant as well as A7 engined specials) - IIRC silicone hoses are OK as long as they are not modern bright colours (eg Samco blue) but black but I am not sure if a Denso, rather than a Lucas, alternator would be OK if not going for total loss electrical system.
Cheers
Mike
As many folk on here must have done, an alternator conversion is/was common DIY mod for those of us that run/ran BMC/BLMC/BL A Series engined cars of the late 1950s to early 1970s that were 12V dynamo equipped, such as MG Midgets, Austin Healey Sprites, Austin A35, Morris Minors and Minis.
This was primarily a way to keep going or improve everyday transport budget secondhand cars - such as my rusty 850 Mini and 850 Mini van in the 1980s. This had the advantage of not having to pick which two electrical items from the menu to use on a wet, cold night - wipers and lights, but no heater/‘de-mister’ (re-distributor of interior fug) (as for your home installed radio - nae chance to keep you company on a long journey). Scrap cars were a source of Lucas alternators (and if unlucky you had a core one to use for an exchange rebuilt item) and alternator plugs, as well as splashing out for a new alternator at Lucas depots or Minispares Centre etc and the conversion to negative earth done at the same time; quality issues with replacement voltage regulators was a factor too (and still is) as is lack of folk who have the knowledge and skills to adjust /service/ repair them (rather than me who ineffectually, ignorantly and incompetently fiddled with voltage regulators in the dark using a Haynes car manual).
Now as an owner of a 1961 Austin Healey Sprite MkII for fun, not everyday transport, I have got it charging its battery properly by having the original Lucas C39 dynamo rebuilt and obtaining a genuine Lucas voltage regulator that has been properly checked/serviced (thanks Dr John E Davies for sorting these along with my rev counter gearbox). It also allows my original rev counter to work as it is driven off the rear of the dynamo through a tiny reduction gearbox. Without such help until recently I would have just switched to a Lucas alternator and change the car from positive earth to negative earth and had to fit a later electrically powered rev counter (not with the correct lovely Healey style face) to replace my cable driven one. An expensive alternative these days are the alternators that externally look like Lucas dynamos - e.g. Dynamators - including the option of one with the rev counter take off.
Another modern option for my case is the availability of small lightweight Japanese alternators by Denso. This is a tempting, if not period-ish looking at all, instead of worrying about the quality now of recently produced ‘Lucas’ alternators.
Enough rambling. But it highlights how options change with time and how cost, desirability and availability of mods change as well as one’s circumstances, transport requirements and perspective.
If we go back to the thoughts of impecunious enthusiasts of the 1950s-1980s, people would fit what was available at that time that could meet their needs in terms of availability and cost of a replacement components/conversion, skill and tools and a place to fit it, and if there was any choice what additional advantage it offered beyond whether they could afford/obtain/fit it. Noting when this was someone’s only mode of transport, rather than an additional leisure vehicle, then it had to be got mobile again quickly and economically, often fixed in the street with a few tools. If Denso alternators were available and cheap in the 1980s my Minis would have had them as a quality good value upgrade to improve reliability and useability, my Sprite will stay with positive earth and a dynamo until I face a problem I cannot fix with the dynamo and voltage regulator - if that happens will be a Dynamator conversion if I can stretch to the extra expense, if not a good Lucas alternator (if one can be found) and accept the loss of rev counter drive and use of a very obviously wrong looking rev counter gauge. I note you can now even buy again positive earth ‘Lucas’ dynamos as well as positive earth ‘Dynamators’, but not sure why anyone would bother with either conversion as positive earth - why not switch to neg earth at the same time (and neg earth dynamos and Dynamators more readily available and wider choice).
It is interesting to see what the 750 Motor Club Historic Formula 750 racers count as in period mods (I do understand that VSCC are thinking of a different period and H750 Formula includes Reliant as well as A7 engined specials) - IIRC silicone hoses are OK as long as they are not modern bright colours (eg Samco blue) but black but I am not sure if a Denso, rather than a Lucas, alternator would be OK if not going for total loss electrical system.
Cheers
Mike