THE OFFICIAL: E85 Fuel Conversion Thread
Former Vendor
Joined: Dec 2004
Posts: 1,708
Likes: 1
From: Woodstock IL
Yeah, I knew about the in-tank pump, already planned to be eliminated, so I neglected to bring it up...
I've sent an inquiry to Unwired Tools re: E85 compatibility. If I get a response, I'll post back.
I've sent an inquiry to Unwired Tools re: E85 compatibility. If I get a response, I'll post back.
Instructor
Joined: Aug 2006
Posts: 161
Likes: 0
From: Norway
To maintain the original tank and fuel lines/system, an option could be to run on a E85/Gaz mix. 10% E85 is already used in regular pump gaz, and many "experts say 20% would be OK for most old cars without doing damage to the fuel system. I assume most of these "experts" also have added a good safety margin for their advice, so maybe 30% E85 could be safe for an acceptable amount of time (until total restoration is due anyway).
On 91 and 93 octane gaz a 30% E85 mix would boost the octane about 5-6% and the needed amount of extra fuel is below 10% which maybe the original system might be able to handle with just a shark tune? The 70% Gaz will take care of lubrication and the 30% E85 would clean off carbon buildup over time and cool down the combustion. How much extra boost could you add to a SC/Turbo engine with 5% higher octane, and how much calculated power would that add? I'm sure Corky Bell has the formulas for calculating this (too long since I read his books to remember).
I'm no expert here, just throwing out ideas, but I do use a tank of 20% E85 mix every now and then, especially in the winter to get condensation water out of the tank, and whenever I need to pass a smog test
Interesting thread.
On 91 and 93 octane gaz a 30% E85 mix would boost the octane about 5-6% and the needed amount of extra fuel is below 10% which maybe the original system might be able to handle with just a shark tune? The 70% Gaz will take care of lubrication and the 30% E85 would clean off carbon buildup over time and cool down the combustion. How much extra boost could you add to a SC/Turbo engine with 5% higher octane, and how much calculated power would that add? I'm sure Corky Bell has the formulas for calculating this (too long since I read his books to remember).
I'm no expert here, just throwing out ideas, but I do use a tank of 20% E85 mix every now and then, especially in the winter to get condensation water out of the tank, and whenever I need to pass a smog test
Interesting thread.
Former Vendor
Joined: Dec 2004
Posts: 1,708
Likes: 1
From: Woodstock IL
Nice thoughts, however, a couple of clarifications are worth mentioning.
Firstly, E85 is a specific mixture of ethanol and gasoline, nominally 85:15, although in colder months and in northern states it can vary by as much as 70:30. So your statements about blending gasolines with E85 is not quite accurate. Those blended gasolines you are referring to are actually 10:90 rations of ethanol-to-gasoline (i.e. NOT E85 + gasoline mixtures). It may seem like splitting hairs, but it is an important distinction...
More importantly, the statement about up to 20% being safe to run is only valid on cars produced from 1995 onward. Federal regulations required manufacturers to use ethanol-safe fuel system components from 1995 onward, so those cars are generally OK from a fuel system integrity perspective with essentially ANY mixture of ethanol; but there is obviously no provision for most of us who are running much older cars. There was a very interesting article recently in Panorama on this topic that referenced an earlier article citing some expert opinions on the matter for owners of really early cars, like those running carbs and such from the late 60s and early 70s. Unfortunately, I can't put my hands on the article at the moment...but I'll try to find it and post back.
In any event, the issue is manifold for older cars, with primary concerns being the ability of older seals and fuel-carrying equipment to withstand ethanol mixtures in gasoline, as well as the impact to fuel mixtures given the significant difference in power yield with ethanol. Simply put, older fueling systems are rudimentary at best in terms of adjusting for fuel-air variables, and there simply isn't any good way to make them compatible with E85, particularly considering that you never know exactly what your getting out of the pump. Even for EFI-equipped cars, without having an E85 sensor that dynamically detects the amount of ethanol in the mixture, you are running great risk with your engine if you just dump E85 or any ethanol mix beyond 20% into your tank and expect your ECU to be able to compensate appropriately.
Also, FWIW, those E85 sensors are not cheap. The least expensive one I've found is $355 new. There are a handful of aftermarket ECUs that can take input from the sensor (and fortunately my DTAFast S60 Pro is one of them). I believe Megasquirt can too, not sure about the Motronic stuff or any of the aftermarket options for the 2.5L platform.
IMO, after all the digging and research I've done, E85 conversion on a pre-1995 car is extremely hard to justify from a classic ROI perspective. It would take something like 10 years at 15K miles per year for it to pay for itself with gasoline at <$4/gal prices. The justification on properly modified and equipped cars is the ability to have a highly tuned motor that can take advantage of E85 as cheap race gas for high compression or high-boost forced induction applications.
Firstly, E85 is a specific mixture of ethanol and gasoline, nominally 85:15, although in colder months and in northern states it can vary by as much as 70:30. So your statements about blending gasolines with E85 is not quite accurate. Those blended gasolines you are referring to are actually 10:90 rations of ethanol-to-gasoline (i.e. NOT E85 + gasoline mixtures). It may seem like splitting hairs, but it is an important distinction...
More importantly, the statement about up to 20% being safe to run is only valid on cars produced from 1995 onward. Federal regulations required manufacturers to use ethanol-safe fuel system components from 1995 onward, so those cars are generally OK from a fuel system integrity perspective with essentially ANY mixture of ethanol; but there is obviously no provision for most of us who are running much older cars. There was a very interesting article recently in Panorama on this topic that referenced an earlier article citing some expert opinions on the matter for owners of really early cars, like those running carbs and such from the late 60s and early 70s. Unfortunately, I can't put my hands on the article at the moment...but I'll try to find it and post back.
In any event, the issue is manifold for older cars, with primary concerns being the ability of older seals and fuel-carrying equipment to withstand ethanol mixtures in gasoline, as well as the impact to fuel mixtures given the significant difference in power yield with ethanol. Simply put, older fueling systems are rudimentary at best in terms of adjusting for fuel-air variables, and there simply isn't any good way to make them compatible with E85, particularly considering that you never know exactly what your getting out of the pump. Even for EFI-equipped cars, without having an E85 sensor that dynamically detects the amount of ethanol in the mixture, you are running great risk with your engine if you just dump E85 or any ethanol mix beyond 20% into your tank and expect your ECU to be able to compensate appropriately.
Also, FWIW, those E85 sensors are not cheap. The least expensive one I've found is $355 new. There are a handful of aftermarket ECUs that can take input from the sensor (and fortunately my DTAFast S60 Pro is one of them). I believe Megasquirt can too, not sure about the Motronic stuff or any of the aftermarket options for the 2.5L platform.
IMO, after all the digging and research I've done, E85 conversion on a pre-1995 car is extremely hard to justify from a classic ROI perspective. It would take something like 10 years at 15K miles per year for it to pay for itself with gasoline at <$4/gal prices. The justification on properly modified and equipped cars is the ability to have a highly tuned motor that can take advantage of E85 as cheap race gas for high compression or high-boost forced induction applications.
Rennlist Member
Joined: Dec 2001
Posts: 25,186
Likes: 105
Three Wheelin'
Joined: Mar 2006
Posts: 1,813
Likes: 0
From: San Diego / Las Vegas
100% the ONLY way, or to stick it to the middle east. At 10years at 15k a year I bet you lost money, the threshold difference in E85 sucks and only doesn't suck sometimes if your other option is premium which it is in our case. The gas mileage is absolutely worse.
I converted my 951 over (by the way I went through a fuel pump during that period, imagine that) and for my commute to Vegas-San Diego It was close to a 5+ gallon difference in 91 and E85. I basically had 2 maps and converted over to 91 to make the commute trip as I wouldn't make it to Vegas or back (330mile trip) on the 16+ gallon tank.
However the drivability on a boosted car was excellent, and hated 91 at any other time other than the long freeway trips.
Also when you tune for E85, you tune on the winter blend when it is 75:25 and you run a bit lean, then on 85:15 you are only slightly rich or just do whatever. In fact the great thing with the E85 is the fact that you can run it leaner especially at idle and the cooler temps of the winter makes it no problem...
Has anyone converted to E85 yet on the 928? Brenden?
I converted my 951 over (by the way I went through a fuel pump during that period, imagine that) and for my commute to Vegas-San Diego It was close to a 5+ gallon difference in 91 and E85. I basically had 2 maps and converted over to 91 to make the commute trip as I wouldn't make it to Vegas or back (330mile trip) on the 16+ gallon tank.
However the drivability on a boosted car was excellent, and hated 91 at any other time other than the long freeway trips.
Also when you tune for E85, you tune on the winter blend when it is 75:25 and you run a bit lean, then on 85:15 you are only slightly rich or just do whatever. In fact the great thing with the E85 is the fact that you can run it leaner especially at idle and the cooler temps of the winter makes it no problem...
Has anyone converted to E85 yet on the 928? Brenden?
Rennlist Member
Joined: Dec 2001
Posts: 25,186
Likes: 105
I have most all the parts. But its a totally new fuel system. No parts carried over from the original car (78 body). SS hard line, aluminum tanks to be coated/anodized, compatible pumps, etc. -10 everywhere, -10 fuel rail, etc.
Former Vendor
Joined: Dec 2004
Posts: 1,708
Likes: 1
From: Woodstock IL
Brendan, I'd be very very interested in pix and/or more details of where you sourced the bits for the 928 conversion. I have a high compression motor waiting to be built for my '80 Euroshark, and E85 is high on the list of things I'd like to do when I get around to that project. PM me if you want.
Rennlist Member
Joined: Dec 2001
Posts: 25,186
Likes: 105
The fuel line is the thin wall stuff from here:
http://www.speedymetals.com/ps-4472-...-annealed.aspx
The fittings are the hard anodized stuff from any of the russell, earls, etc makers that you can get through summit racing.
I found an "ethanol compatible" pump that may or may not work, but it was 50 bucks.
The fuel filters (ethanol is a sort of scouring agent for steel, aluminum, so it picks up crap and moves it) are from Fuel Labs, as will the ethanol compatible MAIN pump (two pumps - one pick up from tank, and one pressure from surge tank)
The fuel rail is from here:
http://www.rossmachineracing.com/dash10.html
And I had them machine the proper placement of the injector holes, and the end threads. A fellow 928 guy was nice enough to give me the on-center measurements.
I am getting some "critique" of the placement and safety of my fuel cells here:
https://rennlist.com/forums/racing-a...r-welding.html
But its mostly about the safety of having a bottom feeder tank.
http://www.speedymetals.com/ps-4472-...-annealed.aspx
The fittings are the hard anodized stuff from any of the russell, earls, etc makers that you can get through summit racing.
I found an "ethanol compatible" pump that may or may not work, but it was 50 bucks.
The fuel filters (ethanol is a sort of scouring agent for steel, aluminum, so it picks up crap and moves it) are from Fuel Labs, as will the ethanol compatible MAIN pump (two pumps - one pick up from tank, and one pressure from surge tank)
The fuel rail is from here:
http://www.rossmachineracing.com/dash10.html
And I had them machine the proper placement of the injector holes, and the end threads. A fellow 928 guy was nice enough to give me the on-center measurements.
I am getting some "critique" of the placement and safety of my fuel cells here:
https://rennlist.com/forums/racing-a...r-welding.html
But its mostly about the safety of having a bottom feeder tank.
Former Vendor
Joined: Dec 2004
Posts: 1,708
Likes: 1
From: Woodstock IL
OK, cool, thanks for that.
The Fuel Lab stuff looks very similar to the Aeromotive components that I'm currently planning to run in my project. All of the Aeromotive stuff is ethanol-safe.
The Fuel Lab stuff looks very similar to the Aeromotive components that I'm currently planning to run in my project. All of the Aeromotive stuff is ethanol-safe.
Former Vendor
Joined: Dec 2004
Posts: 1,708
Likes: 1
From: Woodstock IL
According to their website, they claim that all of their pumps, filters and FPRs are fully alcohol safe for use on full-blown alcy engines...I'm specifically looking at the A1000 series EFI product line...
