Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com - View Single Post - Attention! Alternatorless modders. Get your voltage up

orange4boy · 06-19-2009, 03:34 PM

Thank Christ!

I was wondering about the fuel pressure situation. So depending on the vehicle, low voltage could cause problems or not, but most likely will.

If the injectors are open longer to compensate for lower pressure this would throw off the mpguino because the micro gallons per second would be different than at higher pressure right? This would explain my sudden high mileage numbers when I went from 12V to 18V. Not so much the injector delay.

I wonder how much vaporization is improved at higher pressure? Seems to me a lot from my experience with spray finishing. HVLP - big, slow droplets, conventional 40psi - light fast fog.

Thanks for the info.

Daox, on my van, 2.4L 4cyl the running amp draw is about 15 with everything else off but I noticed it goes up to 20 under hard acceleration (probably the fuel pump). Some of the total is running lights though. I think a 25A dc-dc would do the job.

I just set up mine with one 12V series 27 deep cycle and one 6V Trojan in series to get 18V. They have to be charged separately though. That is one way to save pounds and space. You could tap the 12v to run the stuff that does not care and tap the 18 for the fuel pump and coil. I may just do this at some point since the 18v fries my headlights instantly. I suppose you could find a small 6 volt battery used for certain classic cars somewhere which would match the capacity of your current battery.

06-19-2009, 03:34 PM	#37 (permalink)
orange4boy Master EcoModder Join Date: Aug 2008 Location: The Wet Coast, Kanuckistan. Posts: 1,275 The Golden Egg - '93 Toyota Previa DX 90 day: 31.91 mpg (US) Chewie - '03 Toyota Prius 90 day: 57 mpg (US) The Spaceship - '00 Honda Insight Thanks: 100 Thanked 306 Times in 178 Posts	Thank Christ! I was wondering about the fuel pressure situation. So depending on the vehicle, low voltage could cause problems or not, but most likely will. If the injectors are open longer to compensate for lower pressure this would throw off the mpguino because the micro gallons per second would be different than at higher pressure right? This would explain my sudden high mileage numbers when I went from 12V to 18V. Not so much the injector delay. I wonder how much vaporization is improved at higher pressure? Seems to me a lot from my experience with spray finishing. HVLP - big, slow droplets, conventional 40psi - light fast fog. Thanks for the info. Daox, on my van, 2.4L 4cyl the running amp draw is about 15 with everything else off but I noticed it goes up to 20 under hard acceleration (probably the fuel pump). Some of the total is running lights though. I think a 25A dc-dc would do the job. I just set up mine with one 12V series 27 deep cycle and one 6V Trojan in series to get 18V. They have to be charged separately though. That is one way to save pounds and space. You could tap the 12v to run the stuff that does not care and tap the 18 for the fuel pump and coil. I may just do this at some point since the 18v fries my headlights instantly. I suppose you could find a small 6 volt battery used for certain classic cars somewhere which would match the capacity of your current battery.