just picked up a set of 850 DW's. tuner told me you need 30% higher flow for E85 and i should get 900's of some brand he said he can get cheap and there good but i couldnt pass up a deal of new DW 850's with $200 rebate form which means ill only pay $275 for these!!! the flow chart shows 855 on 3 and 859 on 1. i hope there enough for E85. ive seen 1 maybe 2 guys with 850s running E85 but mostly i see 1000's.
It depends on what mods you will be running and what boost levels you will be hitting, once you run E85 you will have to keep putting that in there its not like a flex fuel car and you can mix it whenever you want. Yes i do believe that you will run those 850's at to much of a duty cycle and might lean the car out, its better to go bigger on the injector so you will not work them as hard, also you will have to think of a new fuel pump up grade.
my plan is to install the new DW 850's, get a turbo xs fmic and 100% or 50/50 bpv and run a map for 93 winter gas and E85 summer map. probable run 20-21psi and call it a day. if the injectors are to high (my tuner will only run 90% IDC!) then we'll do 20-21psi on the winter map and 18-?psi summer E85 map.
Heres the ptential of E85, but also I guess the "downfall".COBB Tuning Blog Subaru WRX The fuel system is a bit over the top. Im sure you wont be getting this deep, but thought it kind of interesting. When are you getting tuned synolimit? Or not date yet?
I'm going to get the intercooler on and go see what we can do before winter ends so we can have a safe winter 93 map, so no real tuning done there as nothing major should change. Then anytime this summer get a E85 map done, so deffenently a few months away.
Do you have alot of pumps that offer E85? One of the downfalls to that is the Alc content is always different everytime you fill up with E85, most of the time its more or less E75 range, I would really think about changing your car over to E85 and do some much needed research.
ive done enough that i feel good about it. tuner has experience and im only going to use it in the summer as it drops to E70 in the winter. I know the months it really is E85 and there is only 1 pump near me that has it. so to get ready to use it i will make sure everything is how it is supposed to be and even fill up at 1/4 and when it gets to 1/4 tank again fill up and then im ready. just to make sure the 93 is all gone. only thing im worried about is the guys on NASIOC pushing 400+TQ. yes 400+!! and 3 have been on stock VF turbos. E85 is just nuts!
If you can, just make sure you have the option to switch maps while on the road, either through AP or tactrix cable. That way you can switch a map based on fuel available. AP would be preferable here, but OS works as well as long as you have your laptop with you on road trips.
I plan on setting up 85 down the road since it's essentially 94-105? octane for cheap. I'll run several maps and be able to switch on the fly. The only thing I really see as being an issue is making sure I'm almost empty before fill up and switching maps as to avoid mixing the fuels to much.
mixing the fuels is fine! i mean E85 is 85% ethanal and 15% gasoline. just because you have a 1/4 tank of gasoline and mix in 3/4 of a tank E85, doesnt mean your cars gonna blow up or anything while you just drive around. HOWEVER driving around like a crazy person and boosting max psi in every gear and going to the drag strip ect.; running 1/4 93 and 3/4 E85 will not be the best idea.
just hold off on the boosting and crazyness till you need another fill up. thats the way i look at it. i have no problem carrying my laptop around and i do need to buy a tactrix cable
Well I was just saying I wouldn't really feel comfortable filling up at 1/4 tank and switching to my E85 map. At the same time I wouldn't want to run my regular gas map either as now my car needs roughly 30% more fuel or it's going to run like crap. Catch 22.
On the other hand, I would feel better about filling up at a 1/4 tank with regular fuel (3/4 regular, 1/4 E85) and running my regular fuel map. I still wouldn't feel great though.
I would feel fine running until close to empty and then filling up to make sure my fuel is as close to my map as possible.
I definitely wouldn't want to run an E85 map with anything less than full E85 though. I mean c'mon, they make maps for 91, 92, 93 octane for a reason. If you feel comfortable running a car with a 93 map with 91 (probably quite similar to running a 3/4, 1/4 tank of E85 to 93) then by all means go for it. I won't risk it though.
i see your point and its a good one, but i think running NO boost will be fine. i have a 93 map and i would run 89 in my car all day! i however would NOT hit boost. as a daily driver all im saying is any gas in your tank will work no matter what map you run. as for running boost, i would only run in my tank what my map was made for. of course id take % into account. i wouldnt fill up with e85 and run my 93 map or vice versa. 89 on a 93 map isnt going to be as bad though
What do you mean by E85 isnt like octane changes?? I did a little math here from a EFI class i took and went back in some notes, Pump gas 93 octane has a latent heat of 150btu and a energy value of 18,900 and power STOICH of 12.5:1 and true E85 is 105 octane with a latent heat of 359 and energy value of 14,021 and power STOICH is 7.4:1. In theory you will make more power under full boost with E85 around mid 7's to high 7's Power STOICH. You can run a 93 octane map while running E85 but you will be really really really lean. Even not pulling any boost i would not run a 93 map with E85 in the tank, cause you will have to be flowing roughly 60% more fuel with E85, Another thing i would go with at least 1000cc injectors so you will not be working them so hard with E85 but yet they are not to big for 93 octane. Now you will have to think about really upgrading your fuel pump. I would get a new fuel pump I ran a Aeromotive A1000 with Aeromotive FPR and get new fuel rails and lines just to be safe. If anyone has any other info please chip in.