Full e85

[rominun]

I hear everyone saying that more than 60% e85 and the hpfp starts maxing out. So, i went yesterday to the gas station and got a full tank of e85, to see what it would do. Im running MHD backend flash and jb4 map 5. Got a rought idle in the morning, so probably going to switch to e85 BEF. Did lots of pulls and the car doesnt lean out at all. Any downsides to running full e85 as a DD?

[xQx]

First, I love your choice of car

Okay, with a Stage 1 LPFP and a Stock HPFP - certainly the common view is you'll max out your fuel system with pure E85. However, everybody who says that are running the aggressive E85 maps which provide more fuel and run higher boost.

On the PUMP map with JB4 Map 5, you'll be nowhere your potential for power output for E85.

I find Map5 to be very conservative. With anything more than 60% E85 (50% E content) you can step it up to Map 7. I doubt you're seeing fuel issues because you're only running about 15psi of boost, not 18 - 19psi which you get from a MHD E60 or JB4 Map 7 tune.

Yes, do the E85 BEF, regardless of your map, you should be running the E85 map if you've got more than 30% ethanol in the tank.

I'm a bit surprised you're not leaning out if you're running 100% E85 with the PUMP BEF or stock BEF. The E85 flash advances the timing so you get the most out of your E content, and pours more fuel down the throat of your car to cope with the lower energy content of Ethanol vs Gas.

As for disadvantages they are thus:
* Worse fuel economy than running gas.
* Increased potential for issue with water in your gas if you leave the car sit for more than a couple of weeks (ethanol absorbs water from the air, gas does not)
* Increased wear on the rubber/plastic components in your fuel system (eg. fuel lines) because alcohol isn't nice to rubber.
* Annoyance factor of always having to go find an E85 pump.
* Cold weather starts can be a problem (though I guess this isn't a big factor in SoCal )


Advantages of your setup:
* More convenient than filling the tank to 60% full with E85 then having to switch pumps and fill the rest with Gas (though most stations now have E85 and 98RON fuel right next to each other now so you don't have to move your car or pay twice)
* In my experience, about 50hp extra at the wheels compared to running PUMP gas

There are almost no performance benefits of running more than 60% ethanol, it's just more convenient to fill with E85 than it is to mix.

[rominun]

Originally Posted by xQx

First, I love your choice of car

Okay, with a Stage 1 LPFP and a Stock HPFP - certainly the common view is you'll max out your fuel system with pure E85. However, everybody who says that are running the aggressive E85 maps which provide more fuel and run higher boost.

On the PUMP map with JB4 Map 5, you'll be nowhere your potential for power output for E85.

I find Map5 to be very conservative. With anything more than 60% E85 (50% E content) you can step it up to Map 7. I doubt you're seeing fuel issues because you're only running about 15psi of boost, not 18 - 19psi which you get from a MHD E60 or JB4 Map 7 tune.

Yes, do the E85 BEF, regardless of your map, you should be running the E85 map if you've got more than 30% ethanol in the tank.

I'm a bit surprised you're not leaning out if you're running 100% E85 with the PUMP BEF or stock BEF. The E85 flash advances the timing so you get the most out of your E content, and pours more fuel down the throat of your car to cope with the lower energy content of Ethanol vs Gas.

As for disadvantages they are thus:
* Worse fuel economy than running gas.
* Increased potential for issue with water in your gas if you leave the car sit for more than a couple of weeks (ethanol absorbs water from the air, gas does not)
* Increased wear on the rubber/plastic components in your fuel system (eg. fuel lines) because alcohol isn't nice to rubber.
* Annoyance factor of always having to go find an E85 pump.
* Cold weather starts can be a problem (though I guess this isn't a big factor in SoCal )


Advantages of your setup:
* More convenient than filling the tank to 60% full with E85 then having to switch pumps and fill the rest with Gas (though most stations now have E85 and 98RON fuel right next to each other now so you don't have to move your car or pay twice)
* In my experience, about 50hp extra at the wheels compared to running PUMP gas

There are almost no performance benefits of running more than 60% ethanol, it's just more convenient to fill with E85 than it is to mix.

Thanks for your comment. Ill be switching flashes tomorrow and see how that feels. My main problem with mixing gas and e85 is that chevron is the only gas station around me that sells e85 and their regular gas is a lot more than other stations, so i would just end up going to 2 different stations and thats a waste of time. Also, e85 is only 2.29 compared to 91 at 3.39 Will be getting port injection soon, so hopefully can utilize full e85 for more performance benefits.

[xQx]

Originally Posted by rominun

Also, e85 is only 2.29 compared to 91 at 3.39 Will be getting port injection soon, so hopefully can utilize full e85 for more performance benefits.

Wow, yeah, fair point. We pay about the same for E85 as we do for E98 here - but that's still a whole lot less than race gas.

Try it & log it. You'll still get a huge amount more power running E85 with the BEF at the same boost compared with Petrol, so I'd say start with Map 5 and watch/log your AFR & HPFP Pressure

If it all looks good, go up to Map 7 to find the limit.

Before you go for a full PI system, it'd pay to read this thread:
http://www.1addicts.com/forums/showthread.php?t=1391008

Apparently, removing the fuel filter on the input of the HPFP and removing a couple of restrictions in the LP & HP fuel lines/rails, you can squeeze more out of the stock system - making the stock turbos your limiting factor, not the HPFP.

[rominun]

Originally Posted by xQx

Wow, yeah, fair point. We pay about the same for E85 as we do for E98 here - but that's still a whole lot less than race gas.

Try it & log it. You'll still get a huge amount more power running E85 with the BEF at the same boost compared with Petrol, so I'd say start with Map 5 and watch/log your AFR & HPFP Pressure

If it all looks good, go up to Map 7 to find the limit.

Before you go for a full PI system, it'd pay to read this thread:
http://www.1addicts.com/forums/showthread.php?t=1391008

Apparently, removing the fuel filter on the input of the HPFP and removing a couple of restrictions in the LP & HP fuel lines/rails, you can squeeze more out of the stock system - making the stock turbos your limiting factor, not the HPFP.

Will sure look into that thanks.