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NG900 and E85 fuel....

5K views 10 replies 6 participants last post by  PMI 
#1 · (Edited)
Since there's the current big-push here in the States for "biofuels" has me wondering about how the NG900 are using it? As I understand the problems are both insufficient "injector volume" and alcohol's corrosiveness to fuel-lines and seals. While most manufacturers have approved e15 for their standard-fuel cars, my manual appears to recommend no-higher than e10 fuel. What's going to happen if the government mandates e15-minimum in a few years? Some local jurisdictions have already required e10-minimum gasolines be-sold there.

Is there an e15 or e85 conversion kit? From what I've read, once e85 is regularly-available, it's a much better performance-fuel if priced-equitably to gasoline. It's 105-octane, burns cooler and loves high-pressure turbo-charging; you just need a larger fuel-tank for the same range.

I was watching Jay Leno visiting Banks Engineering, and Mr. Banks said that the problem with e85 today isn't the fuel, it's the need to be flexible for both gasoline and e85. If designed for just e85, high-performance engines are both feasible and still very fuel-efficient due to the 105-octane and the cooler temps. The problem today to using just e85 is supply and distribution.
 
#2 ·
My '96 SE turbo runs fine on up to about 35% ethanol, with no modifications. Stock injectors, FPR, pump and everything else.

It is a common practice with Subaru turbos and a few other turbocharged cars (ethanol has the same effect as increasing the octane of the fuel, it is a little like running race fuel for the cost of unleaded).

You won't even notice E15.
 
#4 ·
DanS said:
I thought there are problems with moisture in the fuel lines and the need for different sized injectors, engine timing, computer programming, etc. with high ethanol mixtures?
There are no hardware issues on our cars, or most similar cars, however, the fuel pump is not tested or rated by the manufacturer (Walbro) for high ethanol mix like E85 (I asked them). They will not say it will fail, or confirm it will work, in part because of oem agreements with Saab.

Ethanol has less energy (BTUs) per unit volume, and the software in the T5 Trionic ecu can only adjust to it partly, up to about 30%. If you "accidentally" put more than 30% ethanol into the tank, you will get a CEL when the ecu runs out of its adaptation range. So, to burn E85 you would need a custom ecu. genuinesaab.com will provide that for T7 ecu's but not for the T5.

A turbocharged engine can get more power from ethanol mixes (and other high-octane fuels) than from regular unleaded, which offsets the lower energy content of ethanol.

Instead of custom software, you can install injectors which flow more fuel to do the same thing, or other, relatively simple modifications.

You should also know that EPA rules make it extremely difficult to legally convert cars run on public roads to Ethanol and other alternative fuels.

Putting E85 into your car can result in a hefty fine, and converting someone else's car to Ethanol can earn you an appearance in Federal Court. Any discussion about Ethanol should be taken as purely hypothetical, and not for use on public roads.

For that and other reasons, Ethanol is not a popular subject on this board. However, you can find other forums for that kind of discussion, for example Subaru boards, and some dedicated to ethanol and other bio-fuel conversions.
 
#5 ·
PMI:

I have a Renew E85 station in my city that offers:

e85, e20, and unleaded plus.

I have a few ?'s:

Is the unleaded plus the same as offered at other stations?

Have you used the e20? and if so, would you recommend it's use or would it be doable in my car?

Thanks--ode
 
#6 ·
ode said:
Is the unleaded plus the same as offered at other stations?
I don't know, but the gas station employees should be able to tell you. If not, you can call the company and ask. In my area in SE Wisconsin, unleaded contains about, but not exactly, 10% ethanol (E10)

ode said:
Have you used the e20? and if so, would you recommend it's use or would it be doable in my car?
I have run my car on a blend of over 30% ethanol (that would be the equivalent of E30). Much more ethanol than that, and the fuel "maps" stored in the T5 ecu cannot compensate for the ethanol mix w/o other hardware or software modifications.

I would guess that the T7 ecu in the 9-3 model has a similar adaptation range, but I have not tested that.

I can't really "recommend" either way, but in general the effects of using higher ethanol mixes are similar to using a higher octane fuel. Within some limits, the ecu will adapt to the fuel, although it may take a few hard acceleration runs. Boost and peak horsepower may be a tiny bit better, but since the ecu has not been tuned to take best advantage of that, the effect will not be much different than using the higher octane fuel sold at some gas stations.

Since most of the fuel is still gasoline, you will not get the full benefit of E85 fuel, in terms of a cleaner running exhaust, less soot, and so on.

High Ethanol mix was used by Army and Navy planes in WWII, some 1/4 mile dragsters use ethanol, so do Indy 500 cars. The Model-T was an early "flex-fuel" vehicle, although it used a manual switch. Many farmers burn ethanol quietly (and legally) in their farm vehicles not driven on public roads.

Through the 40's and 50's (maybe 60's not sure about that) it was available for high performance cars. It was called "ethyl" at the time and not "premium".

Lead dust was added to gasoline later. Normally, refined lead would be expensive, but the lead dust used in gasoline was a waste product, so using it solved a disposal problem, and at the same time, it allowed the creation of a higher priced, "leaded" or "premium" gasoline.

The rest is pretty much history, google it... :cheesy:
 
#8 ·
PMI said:
I don't know, but the gas station employees should be able to tell you. If not, you can call the company and ask. In my area in SE Wisconsin, unleaded contains about, but not exactly, 10% ethanol (E10)

I have run my car on a blend of over 30% ethanol (that would be the equivalent of E30). Much more ethanol than that, and the fuel "maps" stored in the T5 ecu cannot compensate for the ethanol mix w/o other hardware or software modifications.

I would guess that the T7 ecu in the 9-3 model has a similar adaptation range, but I have not tested that.

I can't really "recommend" either way, but in general the effects of using higher ethanol mixes are similar to using a higher octane fuel. Within some limits, the ecu will adapt to the fuel, although it may take a few hard acceleration runs. Boost and peak horsepower may be a tiny bit better, but since the ecu has not been tuned to take best advantage of that, the effect will not be much different than using the higher octane fuel sold at some gas stations.

Since most of the fuel is still gasoline, you will not get the full benefit of E85 fuel, in terms of a cleaner running exhaust, less soot, and so on.

High Ethanol mix was used by Army and Navy planes in WWII, some 1/4 mile dragsters use ethanol, so do Indy 500 cars. The Model-T was an early "flex-fuel" vehicle, although it used a manual switch. Many farmers burn ethanol quietly (and legally) in their farm vehicles not driven on public roads.

Through the 40's and 50's (maybe 60's not sure about that) it was available for high performance cars. It was called "ethyl" at the time and not "premium".

Lead dust was added to gasoline later. Normally, refined lead would be expensive, but the lead dust used in gasoline was a waste product, so using it solved a disposal problem, and at the same time, it allowed the creation of a higher priced, "leaded" or "premium" gasoline.

The rest is pretty much history, google it... :cheesy:
PMI:

Thanks for the reply, the station here is self serve/pay at the pump w/ no attendant--I looked on there website and it appears that the unleaded plus is 89 octane with 10% ethanol, so it is pretty much the same as at other stations.

What did you do, if anything, to your car to get it ready for the 30+ ethanol?
What benefits do you see from this change (mpg, price, etc.)?

It sounds as if a modification to my ecu and some hardware are suggested to use ethanol more than 10%. For someone who is not mechanically inclined (like me;oops: ), what would you suggest to get it operational to run on more ethanol?

Thanks--ode
 
#10 ·
I know when I use the 94 octane up here (which contains 10 % ethanol) I see about 100 km's less per tank, and the car doesnt run quite as smooth (its still very smooth, but I am picky) My car runs best and performs its best with Shell v-power 91 octane. In fact, every car I have ever driven with ethanol in the tank has seen substanial loss in fuel mileage. Maybe our ethanol is different up here ...
 
#11 ·
ParaMedic_Saab said:
Maybe our ethanol is different up here ...
I don't think slightly different additives would make that much difference. Must be something else.

My MPG on the hwy is about the same with 10% and 30% ethanol, with the NG900 and T5 ecu. I am sure there is some loss in mpg because ethanol does not have as much energy per volume on one hand, but the engine runs better with higher octane. After adaptation, it was not measurable over the same stretch of hwy.
 
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