OUTFXD Posted October 28, 2021 Report Share Posted October 28, 2021 I have been planning a 12v conversion on Jacquiline on the assumption that modern tech(12v Alternator, LED lights, Electric fan, TBI) would result in less parasitic drag on the motor. Does anyone have any actual experience with this? (I'll take the word of someone who has actually put hands on tools over all the internet articles on the.... internet) I would love to hear advice, experiences, and opinions on this matter! Quote Link to comment Share on other sites More sharing options...
Sniper Posted October 28, 2021 Report Share Posted October 28, 2021 I put a 12v alternator in place of a 6v generator. Rewired the car as well as the old wiring was poorly replaced by someone in the past. Using a universal 12v wiring harness but had kept it 6v, bad idea there. Had to change all the bulbs, added nice LED headlights, cleaned up and painted the housings. Replaced the blower motor with a 12v one. Only real issue I had was the wiper motor running way fast, if you have vacuum wipers it is irrelevant. I am in the process of converting to dual throttle body EFI and I do have plans for AC as well as an electrical fan. So 12v was a given, Quote Link to comment Share on other sites More sharing options...
plymouthcranbrook Posted October 28, 2021 Report Share Posted October 28, 2021 Be aware there are 6 volt positive ground alternators out there. I had my generator rebuilt about 7 years ago and have no trouble keeping my battery charged. It even charges some at idle with the lights on. Quote Link to comment Share on other sites More sharing options...
OUTFXD Posted October 28, 2021 Author Report Share Posted October 28, 2021 55 minutes ago, Sniper said: I am in the process of converting to dual throttle body EFI What are you using for the EFI conversion? I was considering something like this Quote Link to comment Share on other sites More sharing options...
Sniper Posted October 29, 2021 Report Share Posted October 29, 2021 My webpage with progress, such as it is. http://www.yourolddad.com/efi Quote Link to comment Share on other sites More sharing options...
chrysler1941 Posted October 29, 2021 Report Share Posted October 29, 2021 My car is 6 volts with no parasitic drag. Definitely cheaper to fix your generator. 1 Quote Link to comment Share on other sites More sharing options...
Sniper Posted October 29, 2021 Report Share Posted October 29, 2021 26 minutes ago, chrysler1941 said: My car is 6 volts with no parasitic drag. Definitely cheaper to fix your generator. Pretty much a well known fact that the solid fan cooling the radiator is a HUGE parasitic drag. 30hp at 5200 rpm is what I have seen. So unless you're running no fan at all you have parasitic drag. Quote Link to comment Share on other sites More sharing options...
chrysler1941 Posted October 29, 2021 Report Share Posted October 29, 2021 7 minutes ago, Sniper said: Pretty much a well known fact that the solid fan cooling the radiator is a HUGE parasitic drag. 30hp at 5200 rpm is what I have seen. So unless you're running no fan at all you have parasitic drag. And fluid coupler, water pump, cold engine oil and so on, but no voltage change or fuel modification will change that. Quote Link to comment Share on other sites More sharing options...
Sniper Posted October 29, 2021 Report Share Posted October 29, 2021 The OP SPECIFICALLY asked about running an electric fan. A voltage change will fix that and will cost effectively eliminate the largest source of easily addressable parasitic drag. Furthermore, there are any number of 12v electric water pump drives out there as well if someone were to get that far into things. 1 Quote Link to comment Share on other sites More sharing options...
chrysler1941 Posted October 29, 2021 Report Share Posted October 29, 2021 2 hours ago, Sniper said: The OP SPECIFICALLY asked about running an electric fan. A voltage change will fix that and will cost effectively eliminate the largest source of easily addressable parasitic drag. Furthermore, there are any number of 12v electric water pump drives out there as well if someone were to get that far into things. No not really. He's writing about 6v Generator vs 12v alternator. Both will drag. Quote Link to comment Share on other sites More sharing options...
Sniper Posted October 29, 2021 Report Share Posted October 29, 2021 I think you are just trying to be argumentative. Quote Link to comment Share on other sites More sharing options...
Bryan Posted October 29, 2021 Report Share Posted October 29, 2021 (edited) I've messed with a few of modules like these at my house..stepping up 12V to 19V to run a laptop off of a car battery. Amazon has 6V to 12V converters for various amps. Wonder how something like these would do for each device? Chrysler1941 - it's not 100% obvious from the title but he is talking about fans also. Amazon.com : step up circuit 6v 12v Edited October 29, 2021 by Bryan 1 Quote Link to comment Share on other sites More sharing options...
Bryan Posted October 29, 2021 Report Share Posted October 29, 2021 7 minutes ago, Sniper said: I think you are just trying to be argumentative. Might just be misunderstanding...I had to go back and look myself.. Quote Link to comment Share on other sites More sharing options...
OUTFXD Posted October 29, 2021 Author Report Share Posted October 29, 2021 1 hour ago, chrysler1941 said: No not really. He's writing about 6v Generator vs 12v alternator. Both will drag. Correct, what I am trying to understand is witch will drag less. IE Subtract the drag from a stock fan and 6v generator and add the drag from a 12v alternator with the additional load from an Electric fan. Witch will have less overall drag on the engine. Quote Link to comment Share on other sites More sharing options...
Sniper Posted October 29, 2021 Report Share Posted October 29, 2021 Electric fans only run when you need them. That mechanical fan runs all the time. Don't think it's unreasonable to claim the electric fan at 12v is a vast improvement in the reduction of parasitic drag. Here's some numbers http://www.carnut.com/ramblin/dyno.html 1 Quote Link to comment Share on other sites More sharing options...
OUTFXD Posted October 29, 2021 Author Report Share Posted October 29, 2021 I recall watching an episode of Engine-masters (your link as I recall) that claimed 30hp loss for a solid fan vs about 1hp loss from additional drag at the alternator so I would agree that its a reasonable assumption, leading to about a 29 horse power reduction in parasitic drag resulting in Better Performance, Efficiency and reduced emissions. But I would rather know than assume. I haven't seen any data for how much drag it takes to turn a 6v generator vs a 12 alternator both under load and free spinning. All things being equal you can assume producing 12v take twice the drag of producing 6v AT FULL LOAD. But then there is the difference in technology. Better Bearings, Lubricants, Electronics, etc. also Running a 12v system that only pushes 6v could be more efficient than a pure 6 volt system etc etc etc. but it seems to me just spinning a 6v generator and a 12v alternator out of the car take about the same exertion of power (not alot) anyway, I am sure I had a point at the beginning of this, but its lost on me now. so just casting out lines looking for information. Thank you all for your input! Quote Link to comment Share on other sites More sharing options...
maok Posted October 29, 2021 Report Share Posted October 29, 2021 12v or 6v will make little difference, if at all, the power ( volt x amp) needed to replenish and supply to the electrical system will be about the same. Hence the drag on the engine will about the same. Electric fan with temp on off switch v constant engine driven fan is different story. 1 1 Quote Link to comment Share on other sites More sharing options...
OUTFXD Posted October 29, 2021 Author Report Share Posted October 29, 2021 9 minutes ago, maok said: 12v or 6v will make little difference, if at all, the power ( volt x amp) needed to replenish and supply to the electrical system will be about the same. Hence the drag on the engine will about the same. Electric fan with temp on off switch v constant engine driven fan is different story. Ahhhh I forgot about amps. a six volt system pushes more amperage than a 12v system thus requiring a more robust wiring harness and requiring more power to turn the generator. Good point! Quote Link to comment Share on other sites More sharing options...
maok Posted October 29, 2021 Report Share Posted October 29, 2021 (edited) 7 minutes ago, OUTFXD said: Ahhhh I forgot about amps. a six volt system pushes more amperage than a 12v system thus requiring a more robust wiring harness and requiring more power to turn the generator. Good point! Not correct, both will do about the same power, regardless of voltage. Edited October 29, 2021 by maok Quote Link to comment Share on other sites More sharing options...
Sniper Posted October 29, 2021 Report Share Posted October 29, 2021 Maok is right. Power is called watts. Watts is simply voltage times amps. So 12v x 10a is 120 watts and 6v x 20a is 120 watts. Double the voltage means half the amps for the same wattage (power). 746 watts is 1 hp. so a 100a 12v alternator is 1200 watts, about 1.6 hp. Assuming perfect efficiency, lol. of course 12v charging systems run at about 13.8v, so that would actually be 1380 watts, less than 2hp in any case. 1 Quote Link to comment Share on other sites More sharing options...
maok Posted October 29, 2021 Report Share Posted October 29, 2021 Just to add to sniper's post, generator/alternator won't output the full capability of it 99% of the time, only when needed, ie on start up to charge the battery. If you have a slightly loose fan belt you will notice it will slip and make noise on start up and then as the demand on the generator alternator is reduced the noise will go away, belt stops slipping. 1 Quote Link to comment Share on other sites More sharing options...
OUTFXD Posted October 30, 2021 Author Report Share Posted October 30, 2021 (edited) so to summerize, a 6 volt system running 20 amps requires about the same power as a 12v system running 10 amps. So swapping to a 12 volt system and adding an electric fan would net a gain of the cost of running a solid fan (about 30 horsepower) minus about 1-2 horsepower. Sorry about this, I dont know a terrible lot about electricity, Beyond it has spent the passed years finding knew and interesting ways to shorten my life! Edited October 30, 2021 by OUTFXD Quote Link to comment Share on other sites More sharing options...
OUTFXD Posted October 30, 2021 Author Report Share Posted October 30, 2021 Also found this for people who want to keep their 6v system. https://www.speedwaymotors.com/Speedway-6-Volt-Electric-Cooling-Fan,56152.html Quote Link to comment Share on other sites More sharing options...
Sniper Posted October 30, 2021 Report Share Posted October 30, 2021 The 16" Speedway fan draws 8-10 amps at 6v (60 watts) and has no shroud. No specified CFM rating though in the Q&A someone claims 2500 cfm size not mentioned, doubtful. I am looking at a Ford Contour fan for my 51. 12v, 17A draw rated at 2200 cfm. That's 204 watts. The speedway fan has straight blades, no shroud. The Contour fan has a shroud and more efficient curved blades. It takes power to move air and there is no way the Speedway fan will out cool the Contour fan. Final data point speedway fan, $134.00, Contour fan, $47.00. Quote Link to comment Share on other sites More sharing options...
OUTFXD Posted October 30, 2021 Author Report Share Posted October 30, 2021 Wow! and the plus of being made by a major manufacturer so you are assured a decent level of quality! Out of interest, How big is the Contour fan? Quote Link to comment Share on other sites More sharing options...
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