West coast easy performance

alwaysblown · Sun, Jul-01-2012, 10:06:16 AM

I've been experimenting with this idea over the last few months. With the factory tune, I've found that the 91 AKI

gasoline fuel is unfortunately past the knock threshhold in the E46 M3. So, I began to dump various liquids into the fuel tank for my own entertainment. Some fared better than others. It's too bad MTBE isn't available by the bucket anywhere.

So far, the best and most readily available result has been the tried and true turbo booze: e85. There's a noticeable increase in low- to mid engine speed output. For months, I've been blending 91 octane with 20% e85. I began with 10%, then moved to 15%, now holding fast at 20%. The engine begins to develop epilepsy at around 30% by vol (this is not considering the ethanol level already blended in the pump gasoline).

It's important to note that for the first fill blend, the engine will operate a little rough at idle. This is temporary and only until the fuel trims stabilize. It can be mitigated by slowly leaning into the ethanol over two refills for the overly concerned. It's not necessary, but it is required to have a functioning closed loop AFR system for this to safely work. Switching back to gasoline poses no problems at all. I've done this a few times because e85 stations are mostly remote to me (unless I'm back in school).

I've had no MILs illuminate and no problems, unless you consider improved performance and -1 mi/gal fuel economy loss a problem. Easy and cheap. Some of the looks I receive while stuffing the "flex fuel" pump into my M3 are sometimes amusing.

Enjoy.

Foo2rama · Sun, Jul-01-2012, 11:26:50 PM

Be carefull, the fuel lines in the e46 are not approved for e85, you might start to to have issues...

Tarmac_E36_M3 · Mon, Jul-02-2012, 01:15:20 AM

Get a flex fuel kit.

Efi said the lines are fine, but a proper tune would help as well as a flex fuel kit.

alwaysblown · Tue, Jul-03-2012, 03:04:28 AM

I've been using E85 on a boosted car from the late 90's for years (while still using the aging factory lines and tank). Though foo2rama is right about the E46 not being designed specifically with E85 in mind, the fuel system was engineered to withstand alcohol-blended fueled which are commonplace in the US. There is an SAE standard for this as well.

Surprised more people aren't turned on to this idea.

xdaznboi · Tue, Jul-03-2012, 03:06:36 AM

I mixed about 1.5 gallons of 100 octane into my tank full of 91 and I was having a GREAT time on the I5

Skeptical to try E85 though, I definitely don't want any rotting plastic lines in my system

Sun, Jul-01-2012, 10:06:16 AM	#1
alwaysblown dragon chaser Join Date: Jun 2012 Posts: 48 Reputation: 0 Location: LA, the shithole of SoCal	West coast easy performance I've been experimenting with this idea over the last few months. With the factory tune, I've found that the 91 AKI gasoline fuel is unfortunately past the knock threshhold in the E46 M3. So, I began to dump various liquids into the fuel tank for my own entertainment. Some fared better than others. It's too bad MTBE isn't available by the bucket anywhere. So far, the best and most readily available result has been the tried and true turbo booze: e85. There's a noticeable increase in low- to mid engine speed output. For months, I've been blending 91 octane with 20% e85. I began with 10%, then moved to 15%, now holding fast at 20%. The engine begins to develop epilepsy at around 30% by vol (this is not considering the ethanol level already blended in the pump gasoline). It's important to note that for the first fill blend, the engine will operate a little rough at idle. This is temporary and only until the fuel trims stabilize. It can be mitigated by slowly leaning into the ethanol over two refills for the overly concerned. It's not necessary, but it is required to have a functioning closed loop AFR system for this to safely work. Switching back to gasoline poses no problems at all. I've done this a few times because e85 stations are mostly remote to me (unless I'm back in school). I've had no MILs illuminate and no problems, unless you consider improved performance and -1 mi/gal fuel economy loss a problem. Easy and cheap. Some of the looks I receive while stuffing the "flex fuel" pump into my M3 are sometimes amusing. Enjoy.

Sun, Jul-01-2012, 11:26:50 PM	#2
Foo2rama 2004 E46 M3 Join Date: Oct 2007 Age: 36 Posts: 4,248 In the garage: '04 BMW M3 Reputation: 0 Location: Costa Mesa	Re: West coast easy performance Be carefull, the fuel lines in the e46 are not approved for e85, you might start to to have issues... __________________ __________________ 2004 Mystic Blau Imola Rot ///M3 Coupe SMG Other Rides 73- 240z - L28 Block w e31 heads - prepping as a track toy 95- Legend Coupe - C32A5 block - totaled while parked 96- Dodge Ram 4x4 5.9 - totaled while parked in a seperate incident

Mon, Jul-02-2012, 01:15:20 AM	#3
Tarmac_E36_M3 If it ain't lightweight, it ain't the right weight. Join Date: Jul 2011 Posts: 3,002 In the garage: '95 BMW M3 '03 BMW M3 Reputation: 0 Location: LA/OC/SD	Re: West coast easy performance Get a flex fuel kit. Efi said the lines are fine, but a proper tune would help as well as a flex fuel kit. __________________ Current: 1969 Ford Mustang Coupe; 351w (5.8L) carb engine; Champion 4 row radiator; Edelbrock Performer RPM Intake Manifold; Edelbrock 750 CFM Carb; 15" Cragar Wheels; 215/60-15 front tires, 255/60-15 rear tires; Doug Tri-Y Headers; Custom 2.5" Dual Side Exit Exhaust w/Xpipe; MSD 6AL; Electric Fuel Pump; March Performance U/D Pulley Set; Monte Carlo Bar; 3200 lbs. 1995 M3; single 3" exhaust after cats; CF hood; Apex ARC-8 17x9" wheels; Conti DW 245 square; BC Racing Coilovers. SOLD: E46 M3 SMG; Intrax coilovers; ACPT CF DS; SS V1 Headers/Section 1; Zionsville Type 17 kit; VAC Ultra light pulley set; BMW MS 4.10; Evolve-R Tune; 2980 lbs.

Tue, Jul-03-2012, 03:04:28 AM	#4
alwaysblown dragon chaser Join Date: Jun 2012 Posts: 48 Reputation: 0 Location: LA, the shithole of SoCal	Re: West coast easy performance I've been using E85 on a boosted car from the late 90's for years (while still using the aging factory lines and tank). Though foo2rama is right about the E46 not being designed specifically with E85 in mind, the fuel system was engineered to withstand alcohol-blended fueled which are commonplace in the US. There is an SAE standard for this as well. Surprised more people aren't turned on to this idea.

Tue, Jul-03-2012, 03:06:36 AM	#5
xdaznboi Registered User Join Date: Jun 2010 Posts: 1,524 In the garage: '06 BMW M3 Reputation: 0 Location: Socal/ Bay Area	Re: West coast easy performance I mixed about 1.5 gallons of 100 octane into my tank full of 91 and I was having a GREAT time on the I5 Skeptical to try E85 though, I definitely don't want any rotting plastic lines in my system __________________ JVT rep Headers \| Depo Smoked Corners \| KW V3\| Ground Control Camber Plate\|B&B Exhaust\| AR 25 Resonator \| Black Out Kit \|CSL Rep Diffuser\| BMW Motorsport 4.10 \| Volk TE 37 \| MOTORSPORT HARDWARE Stud Conversion Kit \| AVT Air Scoop \| Illuminated Door Sills \| VF Engineering Stage 2 \| Dr Vanos Cryogenically Treated Hub \| Ignition Projects Plasma Coils 451.04 WHP 305.46 TQ SAE 91 Pump Gas

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