This thread will be about E85 conversions on the 100 series and people's experience with it. It is also a place where I will document my experience installing the eFlexFuel universal conversion kit on my 2007 LX470 and my journey with it.
The basic idea behind "universal" flex fuel conversion kit is that the control box increases the duration of the signal to the fuel injector to inject a higher volume of fuel when running on E85 or other ethanol blends. The kits supply a pigtail for each injector, you pull the stock plug off each injector and plug it into one side of the pigtail, and the other end of the pigtail plugs onto the injector. This allows the control box to modify the signal to the injector outside of what the factory ECU is doing. This is how the kit is able to work with nearly any fuel injected car. They are usually plug and play and completely reversible.
There are many options to choose from, but I chose the eFlexFuel kit because I believe it is the best. The primary reason is because it includes a GM E85 flex fuel sensor. Believe it or not but the majority of E85 kits do not have this sensor. Somehow they are able to make it work but I believe that the eFlexFuel kit will work even better in all scenarios with this extra sensor.
It also includes a temperature sensor for better cold starts on E85.
Here is what my kit came with. I paid the base price of $350, which is also on the lower-end of the kits on the market, another benefit of this kit.
All wires are nicely covered and all plugs are high quality. Instructions are good and the number of fuel fittings and length of hose is generous, with plenty of extras left over. The fuel filter is OEM Lexus and not included in the kit but was installed at the same time.
The kit was super easy to install and took less than an hour. The only parts under the hood that needed removal were the plastic engine cover, intake and airbox, bracket on driver's side valvecover, and the fuel line from the fuel filter to the fuel rail.
The control box I bolted to the driver's side inner fender and ran the wiring tucked out of the way. The instructions said to keep the wires away from high energy electronics like the alternator or coilpacks so I ran them up over the intake manifold and back towards the firewall.
The GM Flex Fuel sensor I just zip tied to one of the fuse boxes for now. I will likely come up with a more permanent mount before very long.
The kit also has bluetooth and connects to their app. The app lets you see the temperature and the ethanol % of your fuel, along with the injector duty cycle. The app is not 100% reliable but is still labeled a Beta so hopefully it will improve.
I was filled up with E10 85 octane and sure enough that's what the sensor read:
With E10 the max duty cycle I saw at WOT was 67%, with E30 it was 73% and it will only go up from there. I believe the 2UZFE injectors are 275cc at factory fuel pressure of 44psi so they should make almost exactly 270-280 hp at 90% duty cycle on E85.
Then I ran to the local E85 station and added 9 gallons of E85 and filled the tank. Within seconds the sensor was reading 36% ethanol. Nice!
(sorry about the crappy photos)
Truck started and ran flawlessly without even a sputter. Took it out for a few miles later that night all performed awesomely. I believe I feel a power increase along with a change in the engine note but will confirm with science. I recorded a 0-60 run before the conversion and will do a 0-60 run after the conversion with E30 and then later with E85 to see if there's a noticeable difference.
This is the cost of E85 at my local station, $2.15. At another station I can get E10 85 octane for about $2.71. Using the freely available online calculators I will pay off the kit with roughly 5000-7000 miles of driving if only using E85 at current prices depending on what MPG I get. Other locations have differences in prices, though and the cost difference could be larger or smaller. One of the primary purposes I bought my LX470 for is for cross-country road trips so the probability of finding deals and saving money is slightly higher than if I just stayed local.
So please, come along with me on my journey with Flex Fuel and see if the benefits make sense for you! I'm not even sure they make sense for me but I hope to find out! Has anyone else converted their 100 series to E85? I searched but did not find anyone, though lots of Tacoma/Tundra people have.
The basic idea behind "universal" flex fuel conversion kit is that the control box increases the duration of the signal to the fuel injector to inject a higher volume of fuel when running on E85 or other ethanol blends. The kits supply a pigtail for each injector, you pull the stock plug off each injector and plug it into one side of the pigtail, and the other end of the pigtail plugs onto the injector. This allows the control box to modify the signal to the injector outside of what the factory ECU is doing. This is how the kit is able to work with nearly any fuel injected car. They are usually plug and play and completely reversible.
There are many options to choose from, but I chose the eFlexFuel kit because I believe it is the best. The primary reason is because it includes a GM E85 flex fuel sensor. Believe it or not but the majority of E85 kits do not have this sensor. Somehow they are able to make it work but I believe that the eFlexFuel kit will work even better in all scenarios with this extra sensor.
It also includes a temperature sensor for better cold starts on E85.
Here is what my kit came with. I paid the base price of $350, which is also on the lower-end of the kits on the market, another benefit of this kit.
All wires are nicely covered and all plugs are high quality. Instructions are good and the number of fuel fittings and length of hose is generous, with plenty of extras left over. The fuel filter is OEM Lexus and not included in the kit but was installed at the same time.
The kit was super easy to install and took less than an hour. The only parts under the hood that needed removal were the plastic engine cover, intake and airbox, bracket on driver's side valvecover, and the fuel line from the fuel filter to the fuel rail.
The control box I bolted to the driver's side inner fender and ran the wiring tucked out of the way. The instructions said to keep the wires away from high energy electronics like the alternator or coilpacks so I ran them up over the intake manifold and back towards the firewall.
The GM Flex Fuel sensor I just zip tied to one of the fuse boxes for now. I will likely come up with a more permanent mount before very long.
The kit also has bluetooth and connects to their app. The app lets you see the temperature and the ethanol % of your fuel, along with the injector duty cycle. The app is not 100% reliable but is still labeled a Beta so hopefully it will improve.
I was filled up with E10 85 octane and sure enough that's what the sensor read:
With E10 the max duty cycle I saw at WOT was 67%, with E30 it was 73% and it will only go up from there. I believe the 2UZFE injectors are 275cc at factory fuel pressure of 44psi so they should make almost exactly 270-280 hp at 90% duty cycle on E85.
Then I ran to the local E85 station and added 9 gallons of E85 and filled the tank. Within seconds the sensor was reading 36% ethanol. Nice!
(sorry about the crappy photos)
Truck started and ran flawlessly without even a sputter. Took it out for a few miles later that night all performed awesomely. I believe I feel a power increase along with a change in the engine note but will confirm with science. I recorded a 0-60 run before the conversion and will do a 0-60 run after the conversion with E30 and then later with E85 to see if there's a noticeable difference.
This is the cost of E85 at my local station, $2.15. At another station I can get E10 85 octane for about $2.71. Using the freely available online calculators I will pay off the kit with roughly 5000-7000 miles of driving if only using E85 at current prices depending on what MPG I get. Other locations have differences in prices, though and the cost difference could be larger or smaller. One of the primary purposes I bought my LX470 for is for cross-country road trips so the probability of finding deals and saving money is slightly higher than if I just stayed local.
So please, come along with me on my journey with Flex Fuel and see if the benefits make sense for you! I'm not even sure they make sense for me but I hope to find out! Has anyone else converted their 100 series to E85? I searched but did not find anyone, though lots of Tacoma/Tundra people have.
