[924er]

I've searched a grip for this answer so I might as well post it.

I live in Cali, we have nothing but 91 octane, but luckily I live close to a station that sells e85. Now I have experimented with e85 before as I would mix 3 gallons with a 91 octane tank to run Cobb stage 1 aggressive maps just to get rid of timing corrections. Car ran happy for 3 months but then my HPFP a went out. Don't know if it was a coincidence or e85 that causes it. Since then I've been on 91

Now Im full bolt ons running stage 2+ drive map which is meant for 91 and the car pulls okay but I know I have more potential. I'm getting that itch for e85 but this time I would like a custom tune from PTFs.

I've been in contact with them and they keep telling me they usually tune 50/50 e85 Mix which seems pretty aggressive on a stock fuel system. I hear on forums that running no more than 40% on a stock fuel system otherwise I need to upgrade LPFP. I've told them that and keep getting turned away which is why I want to ask the community.

Will a 50/50 mix be okay for a long term daily driver?

I'm not trying to get the most gains or run the most aggressive tune. I want something semi conservative and also I'm still running RFTs as well. I want a safe and reliable e85 mix with a stock fuel system pushing 400whp.

[chandleerr]

can't do more than 40%. YOU HAVE TO UPGRADE FUEL PUMP!!!!!

http://www.n54tech.com/forums/showthread.php?t=17458

from Terry at BMS himself. Install instructions.

[boost junkie]

There's no hard-and-fast rule for how much e85 you can run on the stock pump. You have to look at logs. If the LP is dropping below 50 you need to upgrade. Terry recommends a LPFP upgrade for more than 50% in the 85 faq.

[Ch3ss]

try the ots e85 map from Cobb and logg to see if everythring is good to go.

[924er]

Originally Posted by chandleerr

can't do more than 40%. YOU HAVE TO UPGRADE FUEL PUMP!!!!!

http://www.n54tech.com/forums/showthread.php?t=17458

from Terry at BMS himself. Install instructions.

I know man, I kept telling PFT that and asked if they can tune e40 and they kept replying the same thing. "We normally tune e50 blah blah" lol

They told me I'll have no issues unless I leave the car stored then e85 will mess things up.

I'm not planning on changing my fuel pump anytime soon

[924er]

Originally Posted by boost junkie

There's no hard-and-fast rule for how much e85 you can run on the stock pump. You have to look at logs. If the LP is dropping below 50 you need to upgrade. Terry recommends a LPFP upgrade for more than 50% in the 85 faq.

Interesting. Yeh Ptf did mentioned that as well. They wanted me to start with 50/50 and check for fueling drops but I don't want to take the risk of trial and error and end up replacing a seized fuel pump

[924er]

Originally Posted by Ch3ss

try the ots e85 map from Cobb and logg to see if everythring is good to go.

Yeah I was thinking of that. They do have e30 maps. I'm running 5in FMIC, DCI, and DP. Have you tried it ? How is it

[chepy24]

i was tuned by ptf for e33 for a while now im at e50 with the inline pump. i think they prefer for e50 because it is easier to monitor aka less likely for you to mess something up and then blame ptf (not you specifically)

[924er]

Originally Posted by chepy24

i was tuned by ptf for e33 for a while now im at e50 with the inline pump. i think they prefer for e50 because it is easier to monitor aka less likely for you to mess something up and then blame ptf (not you specifically)

What do you mean by monitor ?

[chepy24]

its easier to put half e85 and half 91 (that is the rule of thumb for e50) however given the variance of e85 and regular gas you may not actually have e50. although you would be close enough. now on trying a different number like e37 (example) its harder to calculate. Thats why its important to test the e85 and i always use the e85 calculator app on my phone lol

[proTUNING Freaks]

924er, to put it simply, we can tune any N54 even with the OEM in-tank pump on either no ethanol (E0) or full ethanol (E100). It doesn't matter what your in-tank pump solution is.

Where the in-tank pump "matters" is how far you can go power wise on any given blend of ethanol. Peak gains (higher RPM) will be roughly the same with and without the LPFP upgrade as OEM N54 turbos lose efficiency there and you can't make nearly as much torque as you can down lower in the RPM range.

In other words, to tune your particular car on the OEM LPFP pump with E50 we'd simply limit your midrange torque which we could also do with full E85 (no blending) for you. Once you do decide to upgrade your LPFP we would adjust your tune free of charge for the additional fuel volume and get all the power the OEM N54 turbos can make everywhere in the RPM range, provided that is your goal tuning wise.

Hopefully that helps clarify any confusion for you and others that may have similar concerns/questions.

[924er]

Originally Posted by proTUNING Freaks

924er, to put it simply, we can tune any N54 even with the OEM in-tank pump on either no ethanol (E0) or full ethanol (E100). It doesn't matter what your in-tank pump solution is.

Where the in-tank pump "matters" is how far you can go power wise on any given blend of ethanol. Peak gains (higher RPM) will be roughly the same with and without the LPFP upgrade as OEM N54 turbos lose efficiency there and you can't make nearly as much torque as you can down lower in the RPM range.

In other words, to tune your particular car on the OEM LPFP pump with E50 we'd simply limit your midrange torque which we could also do with full E85 (no blending) for you. Once you do decide to upgrade your LPFP we would adjust your tune free of charge for the additional fuel volume and get all the power the OEM N54 turbos can make everywhere in the RPM range, provided that is your goal tuning wise.

Hopefully that helps clarify any confusion for you and others that may have similar concerns/questions.

Great, thanks for clarifying. This makes a lot of sense now! So pretty much it's not about how much e85 my pump can handle its about how you tune it? I want a setup to be safe for long term daily driving.

Now I would actually prefer to blend so that my MPG won't suffer as bad since this is my daily driver. What do you think?

Also would you be able to give me a 91 octane tune just in case I'm stranded somewhere where this isn't e85 around I can just switch mad via AP? Will this be an additional charge or included

[proTUNING Freaks]

That is correct. Custom tuning allows us to tailor everything about your tune to make it work with the modifications on the car. Its not a bad idea to upgrade the LPFP but its certainly not required provided you're not after all the midrange power you can get out of OEM N54 turbos.

Fuel mileage is another great reason why the E50 blend is a great compromise and recommended by us other than being easy to blend and remove guesswork.

We can provide you with a custom 91 octane map as well. You also have the option of switching to the OTS 91 octane map if its just for that odd occasion where you run out of E85 and only find 91 at the pump.

[924er]

Originally Posted by proTUNING Freaks

That is correct. Custom tuning allows us to tailor everything about your tune to make it work with the modifications on the car. Its not a bad idea to upgrade the LPFP but its certainly not required provided you're not after all the midrange power you can get out of OEM N54 turbos.

Fuel mileage is another great reason why the E50 blend is a great compromise and recommended by us other than being easy to blend and remove guesswork.

We can provide you with a custom 91 octane map as well. You also have the option of switching to the OTS 91 octane map if its just for that odd occasion where you run out of E85 and only find 91 at the pump.

Will it be an additional charge for a custom 91 map along with an e50 map?

I hear your custom 91 octane maps make the Cobb maps feel slow lol

[jayzF30]

They charge just 99 for additional custom maps for different octane after the first map is done. I paid for a meth map initially full price and then 99 for the additional pump gas map.

[boost junkie]

Originally Posted by chepy24

its easier to put half e85 and half 91 (that is the rule of thumb for e50) however given the variance of e85 and regular gas you may not actually have e50. although you would be close enough. now on trying a different number like e37 (example) its harder to calculate. Thats why its important to test the e85 and i always use the e85 calculator app on my phone lol

Definitely measure your e85 alcohol content. My local station is on the winter blend right now which is e70. I just run that straight with no mix (but I have an inline pump).

[924er]

Originally Posted by jazze90

They charge just 99 for additional custom maps for different octane after the first map is done. I paid for a meth map initially full price and then 99 for the additional pump gas map.

Yeah I think I'm going to have a 91 octane map first. I'm sure the power I'll get will beat any Cobb ots map from what I heard. What u think?

Then later when I'm used to the power I'll get the e85 tune 50/50 mix. I want to ditch this RFTs before I get e85. My car barely hooks as it is now after installing DPs running the weakest map which is the "drive maps"

[924er]

Originally Posted by boost junkie

Definitely measure your e85 alcohol content. My local station is on the winter blend right now which is e70. I just run that straight with no mix (but I have an inline pump).

Yeah well whatever the mix they have at the station I'm sure PTFs will tune it accordingly. They won't just toss me a 50/50 map

I'll have to research how to measure it

[jayzF30]

Originally Posted by 924er

Yeah I think I'm going to have a 91 octane map first. I'm sure the power I'll get will beat any Cobb ots map from what I heard. What u think?

Then later when I'm used to the power I'll get the e85 tune 50/50 mix. I want to ditch this RFTs before I get e85. My car barely hooks as it is now after installing DPs running the weakest map which is the "drive maps"

I never got a custom 91 octane map as we have 93 in abundance here. You'll need good tires after the custom tune for sure especially E85!

[924er]

Originally Posted by jazze90

I never got a custom 91 octane map as we have 93 in abundance here. You'll need good tires after the custom tune for sure especially E85!

Lucky you. Well how was the 93 octane map compared to cobbs aggressive maps?

[mike@x-ph.com]

I would get a stage 2 fuel it kit and then a map properly built for E85 50% blend.

[924er]

Originally Posted by mike@x-ph.com

I would get a stage 2 fuel it kit and then a map properly built for E85 50% blend.

Ok now I'm confused lol

Pro tune freaks are saying they can safely run e50 with OEM pump as long as they limit the mid range torque. They said stage 2 kit will allow them to utilize more power.

I'm trying to keep the fuel system stock for now at least until CPO is up. I'll just get a 91 octane custom tune hopefully that will unleash more power compared to the Cobb "drive" maps