[Public-List] Public-List Digest, Vol 3679, Issue 1
Gordon Laco
mainstay at csolve.net
Tue Jul 17 05:46:39 PDT 2018
Hello Marcelo -
This is a topic fraught with debate… some informed, some purely theoretical. Naval architects and engineers have long understood the ingredients that combine to make propellors effective… rates of slip, pitch, blade area, number of blades, tip clearance, rpm, etc etc are all factors whose influences are well understood. What is still not so well understood is how the prop actually performs in service.
So with that preamble, I will say that the factory supplied 13x8 prop shouldn’t work. It’s tip clearance is much too small for efficient operation, it’s blade area is far too small (but too much for an A4), it has too much pitch, and the combination of it’s characteristics limit the direct drive Atomic IV engine to an RPM where it isn’t developing a fraction of it’s potential rated horsepower.
But…
That prop delivers tremendous thrust at low RPM… we once hove to under power in a 60 knot squall with the rudder hard over and the engine ticking over in gear at 800rpm. We could do over 6.4 knots under power at full throttle… and maneuvering in tight quarters was so positive that more than once observers thought we had a bow thruster. When towing other boats we were like a tug boat.
However, I developed the thought that because 1000 rpm gave us 5.2 knots, a very comfortable and economical cruising speed, 1000 didn’t spin the alternator fast enough to ‘excite’ it into developing power for recharging the batteries. I’d also read that the cooling system wasn’t spinning hard enough either… So I bought a three blade Campbell ‘Sailor’ prop… three narrow blades, smaller diameter, finer pitch. The tip clearance in the aperture was much better… all signs were that this would be an improvement. The promise of higher rpm was attractive.
That boosted rpm, we were amazed that low batteries became fully recharged in only a short time under power; and the engine ran cooler despite the rpm being higher. And we noticed that the boat was significantly quieter under power, due to no longer developing the characteristic thump created by the two bladed prop when it aligned twice per rev with the sternpost, and not having good water flow for an instant... But, top speed in calm conditions was lower, and we noticed two other negatives… towing ability with our dinghy and another yacht was much weaker, and fuel economy was much worse.
I sent a detailed analysis to Campbell, who very generously offered to exchange our prop for another. The second, the one on the shaft now, was larger in diameter, same pitch but with cupped blades. This one still lets the engine get a little higher in revs (but not as high as the first three blade offered) so the charging and cooling issues are still better than the two bladed one, and we can again motor at over 6 knots when we want to, and fuel economy is back where it should be… and last… we had to tow friends in their Columbia 29 and managed that at 6knots for a couple of hours with no difficulty. There is one negative - that is our capability in reverse is much worse than the two blader gave us. With the two bladed prop, we could stop like we had disc brakes when we needed to, and I found the prop walk in reverse very useful when spinning the boat in tight quarters. Our current prop cavitates when in reverse because of the cupped blades… but I’m learning to feel when it’s starting so I can keep reverse thrust on when I need it.
So in conclusion… despite the well documented information textbooks offer (which I taught for years) the proof is in the pudding rather than on the pages… the two bladed prop supplied by the factory which should by all counts be ‘over-propped’ for our engines and boats is actually very good in all respects but for spinning the alternator and possibly cooling… and of course the thump twice per rev.
The current three bladed prop I’ve got is also too much prop according to science, but service proves it’s only almost as good as the two bladed with regards to driving the boat through the water, but is a little better with regard to spinning the alternator and cooling systems. And it’s quieter. But it’s worse in reverse.
So, was changing worth the cost? I don’t really know. Sometimes I miss the brute grunt the boat had under power with the old prop… which according to science that prop couldn’t offer, but did. Sometimes I’m glad that the boat is now so quiet under power. Every Wednesday night race I’m glad of the PHRF rating boost having a three bladed prop gives us… and of course I found tinkering with the props very interesting. I’ve got the two bladed one on my office book shelf beside me now… maybe I’ll put it back on some time just to try it out again...
Gord Laco
www.gordonlaco.com
#426 Surprise
> On Jul 17, 2018, at 8:10 AM, Marcelo D. Gentinetta via Public-List <public-list at lists.alberg30.org> wrote:
>
> Gordon,
> So if I understand your statement correctly, you are a fan of the 2 blade 13 X 8 original prop? This is what I presently have also but at times I have considered a smaller 3 blade prop to prevent “lugging” and low RPMs.
> Marcelo #441
>
>> On Jul 16, 2018, at 5:35 PM, Gordon Laco via Public-List <public-list at lists.alberg30.org> wrote:
>>
>> Well the prop and boat are clean as a whistle… and in heavy weather punching into a head sea or towing another heavier boat, we perform like a tug boat. The boat has loads of ‘grunt’.
>>
>> Fuel economy is superb… engine cooling is well inside the envelope… engine is quiet and smooth. For most of the past fifty years she had the factory supplied two bladed prop… that gave only 1300 rpm at open throttle… but the boat was a little faster… but noisier due to prop thump (not the engine of course)
>>
>> We had a prop with easier pitch that allowed the engine to get up to about 1900 wide open… fuel consumption when through the roof, and maneuvering power was much degraded.
>>
>> I used to teach all that about horsepower when I was on faculty at Georgian Colleges marine tech programme… but the bottom line of course is not how the boat should behave by prediction, rather how she performs in service.
>>
>> Gordon Laco
>> www.gordonlaco.com
>> #426 Surprise
>>
>>
>>
>>> On Jul 16, 2018, at 6:29 PM, Greenhouse, Matthew A. (GSFC-6650) via Public-List <public-list at lists.alberg30.org> wrote:
>>>
>>> Gordon — If you can’t turn 2000 rpm in gear, then you have the wrong prop or it is badly fouled with marine growth. At 1200 one develops only about 8 brake horsepower as opposed to 20 at 2000. That will hurt in bad weather. Also, if the engine is in tune and alignment, then it will be smooth and quiet at all speeds.
>>>
>>> Matt
>>> Friendship 295
>>>
>>> Sent from my iPhone
>>>
>>>> On Jul 16, 2018, at 5:43 PM, "public-list-request at lists.alberg30.org" <public-list-request at lists.alberg30.org> wrote:
>>>>
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>>>> Today's Topics:
>>>>
>>>> 1. Alternators... (Gordon Laco)
>>>> 2. Re: Alternators... (Anders Bro)
>>>> 3. Re: Alternators... (Gordon Laco)
>>>> 4. Re: Alternators... (Anders Bro)
>>>> 5. Re: Alternators... (Gordon Laco)
>>>> 6. Re: Alternators... (Anders Bro)
>>>>
>>>>
>>>> ----------------------------------------------------------------------
>>>>
>>>> Message: 1
>>>> Date: Mon, 16 Jul 2018 16:39:01 -0400
>>>> From: Gordon Laco <mainstay at csolve.net>
>>>> To: Alberg 30 Public List -- open to all
>>>> <public-list at lists.alberg30.org>
>>>> Subject: [Public-List] Alternators...
>>>> Message-ID: <9B9C07F2-237E-44EA-A798-7D5365F11AE5 at csolve.net>
>>>> Content-Type: text/plain; charset=utf-8
>>>>
>>>> Hello friends?
>>>>
>>>> Do any of you have data on what the output curve of our Atomic IV?s alternators will put out at various RPM?s?
>>>>
>>>> I?m looking at Moyer?s modern alternators, and noticed that they give output figures for ?normal operating speed of 2000rpm?. Well even with the boosted rpm our Campbell prop allows, we still don?t get more than 1500 going flat out? we cruise quietly at 1200.
>>>>
>>>> I understand our factory supplied alternators are ?30 amp? but what is it really delivering at real operational rpms?
>>>>
>>>> I understand that at lower rpm?s the alternator isn?t ?excited? so delivers little amperage?But I don?t know what the critical rpm rate is to achieve excitement
>>>>
>>>> I don?t understand this whole subject as well as I?d like to.
>>>>
>>>> Gordon Laco
>>>> #426 Surprise
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> ------------------------------
>>>>
>>>> Message: 2
>>>> Date: Mon, 16 Jul 2018 16:53:40 -0400
>>>> From: Anders Bro <abro.gtu at gmail.com>
>>>> To: Alberg 30 Public List -- open to all
>>>> <public-list at lists.alberg30.org>
>>>> Subject: Re: [Public-List] Alternators...
>>>> Message-ID:
>>>> <CACEd84sxKZn0RiuosopbPPf4S13k4mjzzaLZ=ieJwcoC93ZjMQ at mail.gmail.com>
>>>> Content-Type: text/plain; charset="UTF-8"
>>>>
>>>> Ya, but isn't that alternator rpm and not engine speed? Usually the pulleys
>>>> are sized to have alternator rpm higher than engine rpm.
>>>> Anders
>>>>
>>>> On Jul 16, 2018 4:39 PM, "Gordon Laco via Public-List" <
>>>> public-list at lists.alberg30.org> wrote:
>>>>
>>>> Hello friends?
>>>>
>>>> Do any of you have data on what the output curve of our Atomic IV?s
>>>> alternators will put out at various RPM?s?
>>>>
>>>> I?m looking at Moyer?s modern alternators, and noticed that they give
>>>> output figures for ?normal operating speed of 2000rpm?. Well even with the
>>>> boosted rpm our Campbell prop allows, we still don?t get more than 1500
>>>> going flat out? we cruise quietly at 1200.
>>>>
>>>> I understand our factory supplied alternators are ?30 amp? but what is it
>>>> really delivering at real operational rpms?
>>>>
>>>> I understand that at lower rpm?s the alternator isn?t ?excited? so delivers
>>>> little amperage?But I don?t know what the critical rpm rate is to achieve
>>>> excitement
>>>>
>>>> I don?t understand this whole subject as well as I?d like to.
>>>>
>>>> Gordon Laco
>>>> #426 Surprise
>>>>
>>>>
>>>>
>>>>
>>>> _______________________________________________
>>>> These businesses support your Association:
>>>> http://www.alberg30.org/store/A30supporters.html
>>>> Please support them.
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>>>>
>>>>
>>>> ------------------------------
>>>>
>>>> Message: 3
>>>> Date: Mon, 16 Jul 2018 16:57:28 -0400
>>>> From: Gordon Laco <mainstay at csolve.net>
>>>> To: Alberg 30 Public List -- open to all
>>>> <public-list at lists.alberg30.org>
>>>> Subject: Re: [Public-List] Alternators...
>>>> Message-ID: <2AAE1378-98D2-4A75-A4F0-DA86BA00064D at csolve.net>
>>>> Content-Type: text/plain; charset=utf-8
>>>>
>>>> True, but it?s the engine that has the RPM instrument?
>>>>
>>>> Gordon Laco
>>>> www.gordonlaco.com
>>>> #426 Surprise
>>>>
>>>>
>>>>
>>>>> On Jul 16, 2018, at 4:53 PM, Anders Bro via Public-List <public-list at lists.alberg30.org> wrote:
>>>>>
>>>>> Ya, but isn't that alternator rpm and not engine speed? Usually the pulleys
>>>>> are sized to have alternator rpm higher than engine rpm.
>>>>> Anders
>>>>>
>>>>> On Jul 16, 2018 4:39 PM, "Gordon Laco via Public-List" <
>>>>> public-list at lists.alberg30.org> wrote:
>>>>>
>>>>> Hello friends?
>>>>>
>>>>> Do any of you have data on what the output curve of our Atomic IV?s
>>>>> alternators will put out at various RPM?s?
>>>>>
>>>>> I?m looking at Moyer?s modern alternators, and noticed that they give
>>>>> output figures for ?normal operating speed of 2000rpm?. Well even with the
>>>>> boosted rpm our Campbell prop allows, we still don?t get more than 1500
>>>>> going flat out? we cruise quietly at 1200.
>>>>>
>>>>> I understand our factory supplied alternators are ?30 amp? but what is it
>>>>> really delivering at real operational rpms?
>>>>>
>>>>> I understand that at lower rpm?s the alternator isn?t ?excited? so delivers
>>>>> little amperage?But I don?t know what the critical rpm rate is to achieve
>>>>> excitement
>>>>>
>>>>> I don?t understand this whole subject as well as I?d like to.
>>>>>
>>>>> Gordon Laco
>>>>> #426 Surprise
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> _______________________________________________
>>>>> These businesses support your Association:
>>>>> http://www.alberg30.org/store/A30supporters.html
>>>>> Please support them.
>>>>> _______________________________________________
>>>>> Public-List mailing list
>>>>> Public-List at lists.alberg30.org
>>>>> http://lists.alberg30.org/listinfo.cgi/public-list-alberg30.org
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>>>>> These businesses support your Association:
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>>>>> http://lists.alberg30.org/listinfo.cgi/public-list-alberg30.org
>>>>
>>>>
>>>>
>>>> ------------------------------
>>>>
>>>> Message: 4
>>>> Date: Mon, 16 Jul 2018 17:21:35 -0400
>>>> From: Anders Bro <abro.gtu at gmail.com>
>>>> To: Alberg 30 Public List -- open to all
>>>> <public-list at lists.alberg30.org>
>>>> Subject: Re: [Public-List] Alternators...
>>>> Message-ID:
>>>> <CACEd84t7K3n3eCvAF0SM+aU_8OgaCCpJ1zNQLeLtRwRSkjefDA at mail.gmail.com>
>>>> Content-Type: text/plain; charset="UTF-8"
>>>>
>>>> Yes, so multiply that rpm by the pulley ratio to come up with alternator
>>>> rpm, and make your own plot of output vs engine rpm?
>>>>
>>>> On Mon, Jul 16, 2018, 4:57 PM Gordon Laco via Public-List <
>>>> public-list at lists.alberg30.org> wrote:
>>>>
>>>>> True, but it?s the engine that has the RPM instrument?
>>>>>
>>>>> Gordon Laco
>>>>> www.gordonlaco.com
>>>>> #426 Surprise
>>>>>
>>>>>
>>>>>
>>>>>> On Jul 16, 2018, at 4:53 PM, Anders Bro via Public-List <
>>>>> public-list at lists.alberg30.org> wrote:
>>>>>>
>>>>>> Ya, but isn't that alternator rpm and not engine speed? Usually the
>>>>> pulleys
>>>>>> are sized to have alternator rpm higher than engine rpm.
>>>>>> Anders
>>>>>>
>>>>>> On Jul 16, 2018 4:39 PM, "Gordon Laco via Public-List" <
>>>>>> public-list at lists.alberg30.org> wrote:
>>>>>>
>>>>>> Hello friends?
>>>>>>
>>>>>> Do any of you have data on what the output curve of our Atomic IV?s
>>>>>> alternators will put out at various RPM?s?
>>>>>>
>>>>>> I?m looking at Moyer?s modern alternators, and noticed that they give
>>>>>> output figures for ?normal operating speed of 2000rpm?. Well even with
>>>>> the
>>>>>> boosted rpm our Campbell prop allows, we still don?t get more than 1500
>>>>>> going flat out? we cruise quietly at 1200.
>>>>>>
>>>>>> I understand our factory supplied alternators are ?30 amp? but what is it
>>>>>> really delivering at real operational rpms?
>>>>>>
>>>>>> I understand that at lower rpm?s the alternator isn?t ?excited? so
>>>>> delivers
>>>>>> little amperage?But I don?t know what the critical rpm rate is to achieve
>>>>>> excitement
>>>>>>
>>>>>> I don?t understand this whole subject as well as I?d like to.
>>>>>>
>>>>>> Gordon Laco
>>>>>> #426 Surprise
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>> _______________________________________________
>>>>>> These businesses support your Association:
>>>>>> http://www.alberg30.org/store/A30supporters.html
>>>>>> Please support them.
>>>>>> _______________________________________________
>>>>>> Public-List mailing list
>>>>>> Public-List at lists.alberg30.org
>>>>>> http://lists.alberg30.org/listinfo.cgi/public-list-alberg30.org
>>>>>> _______________________________________________
>>>>>> These businesses support your Association:
>>>>>> http://www.alberg30.org/store/A30supporters.html
>>>>>> Please support them.
>>>>>> _______________________________________________
>>>>>> Public-List mailing list
>>>>>> Public-List at lists.alberg30.org
>>>>>> http://lists.alberg30.org/listinfo.cgi/public-list-alberg30.org
>>>>>
>>>>> _______________________________________________
>>>>> These businesses support your Association:
>>>>> http://www.alberg30.org/store/A30supporters.html
>>>>> Please support them.
>>>>> _______________________________________________
>>>>> Public-List mailing list
>>>>> Public-List at lists.alberg30.org
>>>>> http://lists.alberg30.org/listinfo.cgi/public-list-alberg30.org
>>>>>
>>>>
>>>>
>>>> ------------------------------
>>>>
>>>> Message: 5
>>>> Date: Mon, 16 Jul 2018 17:37:06 -0400
>>>> From: Gordon Laco <mainstay at csolve.net>
>>>> To: Alberg 30 Public List -- open to all
>>>> <public-list at lists.alberg30.org>
>>>> Subject: Re: [Public-List] Alternators...
>>>> Message-ID: <B8AA3311-6F99-4642-B15F-32EFC1C2D17E at csolve.net>
>>>> Content-Type: text/plain; charset=utf-8
>>>>
>>>> Well that?s all quite logical? but the missing ingredient is the output by the alternator at various rpm.
>>>>
>>>> Gordon Laco
>>>> www.gordonlaco.com
>>>>
>>>>
>>>>
>>>>
>>>>> On Jul 16, 2018, at 5:21 PM, Anders Bro via Public-List <public-list at lists.alberg30.org> wrote:
>>>>>
>>>>> Yes, so multiply that rpm by the pulley ratio to come up with alternator
>>>>> rpm, and make your own plot of output vs engine rpm?
>>>>>
>>>>> On Mon, Jul 16, 2018, 4:57 PM Gordon Laco via Public-List <
>>>>> public-list at lists.alberg30.org> wrote:
>>>>>
>>>>>> True, but it?s the engine that has the RPM instrument?
>>>>>>
>>>>>> Gordon Laco
>>>>>> www.gordonlaco.com
>>>>>> #426 Surprise
>>>>>>
>>>>>>
>>>>>>
>>>>>>> On Jul 16, 2018, at 4:53 PM, Anders Bro via Public-List <
>>>>>> public-list at lists.alberg30.org> wrote:
>>>>>>>
>>>>>>> Ya, but isn't that alternator rpm and not engine speed? Usually the
>>>>>> pulleys
>>>>>>> are sized to have alternator rpm higher than engine rpm.
>>>>>>> Anders
>>>>>>>
>>>>>>> On Jul 16, 2018 4:39 PM, "Gordon Laco via Public-List" <
>>>>>>> public-list at lists.alberg30.org> wrote:
>>>>>>>
>>>>>>> Hello friends?
>>>>>>>
>>>>>>> Do any of you have data on what the output curve of our Atomic IV?s
>>>>>>> alternators will put out at various RPM?s?
>>>>>>>
>>>>>>> I?m looking at Moyer?s modern alternators, and noticed that they give
>>>>>>> output figures for ?normal operating speed of 2000rpm?. Well even with
>>>>>> the
>>>>>>> boosted rpm our Campbell prop allows, we still don?t get more than 1500
>>>>>>> going flat out? we cruise quietly at 1200.
>>>>>>>
>>>>>>> I understand our factory supplied alternators are ?30 amp? but what is it
>>>>>>> really delivering at real operational rpms?
>>>>>>>
>>>>>>> I understand that at lower rpm?s the alternator isn?t ?excited? so
>>>>>> delivers
>>>>>>> little amperage?But I don?t know what the critical rpm rate is to achieve
>>>>>>> excitement
>>>>>>>
>>>>>>> I don?t understand this whole subject as well as I?d like to.
>>>>>>>
>>>>>>> Gordon Laco
>>>>>>> #426 Surprise
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> _______________________________________________
>>>>>>> These businesses support your Association:
>>>>>>> http://www.alberg30.org/store/A30supporters.html
>>>>>>> Please support them.
>>>>>>> _______________________________________________
>>>>>>> Public-List mailing list
>>>>>>> Public-List at lists.alberg30.org
>>>>>>> http://lists.alberg30.org/listinfo.cgi/public-list-alberg30.org
>>>>>>> _______________________________________________
>>>>>>> These businesses support your Association:
>>>>>>> http://www.alberg30.org/store/A30supporters.html
>>>>>>> Please support them.
>>>>>>> _______________________________________________
>>>>>>> Public-List mailing list
>>>>>>> Public-List at lists.alberg30.org
>>>>>>> http://lists.alberg30.org/listinfo.cgi/public-list-alberg30.org
>>>>>>
>>>>>> _______________________________________________
>>>>>> These businesses support your Association:
>>>>>> http://www.alberg30.org/store/A30supporters.html
>>>>>> Please support them.
>>>>>> _______________________________________________
>>>>>> Public-List mailing list
>>>>>> Public-List at lists.alberg30.org
>>>>>> http://lists.alberg30.org/listinfo.cgi/public-list-alberg30.org
>>>>>>
>>>>> _______________________________________________
>>>>> These businesses support your Association:
>>>>> http://www.alberg30.org/store/A30supporters.html
>>>>> Please support them.
>>>>> _______________________________________________
>>>>> Public-List mailing list
>>>>> Public-List at lists.alberg30.org
>>>>> http://lists.alberg30.org/listinfo.cgi/public-list-alberg30.org
>>>>
>>>>
>>>>
>>>> ------------------------------
>>>>
>>>> Message: 6
>>>> Date: Mon, 16 Jul 2018 17:42:49 -0400
>>>> From: Anders Bro <abro.gtu at gmail.com>
>>>> To: Alberg 30 Public List -- open to all
>>>> <public-list at lists.alberg30.org>
>>>> Subject: Re: [Public-List] Alternators...
>>>> Message-ID:
>>>> <CACEd84v1VXz1Mnm36vK9v=9bBY2mRfCKuJhQBbXXhK8BYfPWFA at mail.gmail.com>
>>>> Content-Type: text/plain; charset="UTF-8"
>>>>
>>>> Oops, I thought you had that :-( sorry about that. Maybe get it from Delco,
>>>> or whoever the mfg is??
>>>>
>>>> On Mon, Jul 16, 2018, 5:37 PM Gordon Laco via Public-List <
>>>> public-list at lists.alberg30.org> wrote:
>>>>
>>>>> Well that?s all quite logical? but the missing ingredient is the output by
>>>>> the alternator at various rpm.
>>>>>
>>>>> Gordon Laco
>>>>> www.gordonlaco.com
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>> On Jul 16, 2018, at 5:21 PM, Anders Bro via Public-List <
>>>>> public-list at lists.alberg30.org> wrote:
>>>>>>
>>>>>> Yes, so multiply that rpm by the pulley ratio to come up with alternator
>>>>>> rpm, and make your own plot of output vs engine rpm?
>>>>>>
>>>>>> On Mon, Jul 16, 2018, 4:57 PM Gordon Laco via Public-List <
>>>>>> public-list at lists.alberg30.org> wrote:
>>>>>>
>>>>>>> True, but it?s the engine that has the RPM instrument?
>>>>>>>
>>>>>>> Gordon Laco
>>>>>>> www.gordonlaco.com
>>>>>>> #426 Surprise
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>> On Jul 16, 2018, at 4:53 PM, Anders Bro via Public-List <
>>>>>>> public-list at lists.alberg30.org> wrote:
>>>>>>>>
>>>>>>>> Ya, but isn't that alternator rpm and not engine speed? Usually the
>>>>>>> pulleys
>>>>>>>> are sized to have alternator rpm higher than engine rpm.
>>>>>>>> Anders
>>>>>>>>
>>>>>>>> On Jul 16, 2018 4:39 PM, "Gordon Laco via Public-List" <
>>>>>>>> public-list at lists.alberg30.org> wrote:
>>>>>>>>
>>>>>>>> Hello friends?
>>>>>>>>
>>>>>>>> Do any of you have data on what the output curve of our Atomic IV?s
>>>>>>>> alternators will put out at various RPM?s?
>>>>>>>>
>>>>>>>> I?m looking at Moyer?s modern alternators, and noticed that they give
>>>>>>>> output figures for ?normal operating speed of 2000rpm?. Well even with
>>>>>>> the
>>>>>>>> boosted rpm our Campbell prop allows, we still don?t get more than 1500
>>>>>>>> going flat out? we cruise quietly at 1200.
>>>>>>>>
>>>>>>>> I understand our factory supplied alternators are ?30 amp? but what is
>>>>> it
>>>>>>>> really delivering at real operational rpms?
>>>>>>>>
>>>>>>>> I understand that at lower rpm?s the alternator isn?t ?excited? so
>>>>>>> delivers
>>>>>>>> little amperage?But I don?t know what the critical rpm rate is to
>>>>> achieve
>>>>>>>> excitement
>>>>>>>>
>>>>>>>> I don?t understand this whole subject as well as I?d like to.
>>>>>>>>
>>>>>>>> Gordon Laco
>>>>>>>> #426 Surprise
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> _______________________________________________
>>>>>>>> These businesses support your Association:
>>>>>>>> http://www.alberg30.org/store/A30supporters.html
>>>>>>>> Please support them.
>>>>>>>> _______________________________________________
>>>>>>>> Public-List mailing list
>>>>>>>> Public-List at lists.alberg30.org
>>>>>>>> http://lists.alberg30.org/listinfo.cgi/public-list-alberg30.org
>>>>>>>> _______________________________________________
>>>>>>>> These businesses support your Association:
>>>>>>>> http://www.alberg30.org/store/A30supporters.html
>>>>>>>> Please support them.
>>>>>>>> _______________________________________________
>>>>>>>> Public-List mailing list
>>>>>>>> Public-List at lists.alberg30.org
>>>>>>>> http://lists.alberg30.org/listinfo.cgi/public-list-alberg30.org
>>>>>>>
>>>>>>> _______________________________________________
>>>>>>> These businesses support your Association:
>>>>>>> http://www.alberg30.org/store/A30supporters.html
>>>>>>> Please support them.
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>>>>>>> Public-List mailing list
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>>>>>>>
>>>>>> _______________________________________________
>>>>>> These businesses support your Association:
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>>>>>> Please support them.
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>>>>>
>>>>> _______________________________________________
>>>>> These businesses support your Association:
>>>>> http://www.alberg30.org/store/A30supporters.html
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>>>>>
>>>>
>>>>
>>>> ------------------------------
>>>>
>>>> Subject: Digest Footer
>>>>
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>>>> ------------------------------
>>>>
>>>> End of Public-List Digest, Vol 3679, Issue 1
>>>> ********************************************
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