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Converting to E85 (ethanol fuel)

okay so i did a little more digging and i found out that it IS in fact LH and the stock injectors are 35.5 psi 167cm3/min ....here's where i got that from http://www.k-jet.org/files/greenbooks/TP30427-1_lh-jet_v2_b23f.pdf so what size injectors would i need to get/where would i get those from?

Thanks -Jake
Then the injector size should be 242cc/min. So try to get something around that value. A little higher than 242cc/min is ok (and actually preferrable depending on the application), but you don't really want to go under 235cc/min or else you will probably start to loose power and get troubles with starting and cold weather.

Also remember that most injector flow rates are listed at 3 bar. That means that you want a set of injectors that flow 268cc/min (25.5lbs/hr) or a little bit more at 3 bar.
 
Thanks for very informative thread.
So i had enough courage to try and run E85 in my 944T.
I went the "cheappo" way by adding bigger injectors.
Initially I had greentops Bosch "357" and I put in Bosch "402" from 3.8L Ford.
If i find a second pair of Bosch "400" from 5.0L CFI Ford I'll definitely put those in, but no luck at the JY as of today. Everything works fine so far (on my second fill up). So, many thanks to you, Frederik.

I have a question though. Before i attempted the injector swap i read about flow rates and different sources list different numbers. I was wondering if i'm within +30% or +42% with respect to the original ones.
Just need some kind of reassurance, I suppose.

thanks again
 
Thanks for very informative thread.
So i had enough courage to try and run E85 in my 944T.
I went the "cheappo" way by adding bigger injectors.
Initially I had greentops Bosch "357" and I put in Bosch "402" from 3.8L Ford.
If i find a second pair of Bosch "400" from 5.0L CFI Ford I'll definitely put those in, but no luck at the JY as of today. Everything works fine so far (on my second fill up). So, many thanks to you, Frederik.

I have a question though. Before i attempted the injector swap i read about flow rates and different sources list different numbers. I was wondering if i'm within +30% or +42% with respect to the original ones.
Just need some kind of reassurance, I suppose.

thanks again
The corrrect number is 42%.

30% is the minimum size increase you can get away with, and that is often recommended for low power cars or NA cars so that they can fill up with both petrol and E85 without worrying about the lambda light showing. I do not really recommend it though since even the NA cars and the stock turbo cars must be able to give enough enrichment on quick throttle changes etc.

The flow of the 402 injectors are 37lb/hr. That is just 15% bigger than stock and I do not recommend that you run those for very long.

The 400 injectors are 46lb/hr though, and that is 43% bigger than stock. those are the injectors I recommend in this case.
 
I know that most guys focus on turbos around this neck of the woods but....

what is the highest static CR someone has been able to get away with on E85? (and what kind of camshaft for the DCR)? This would be really helpful, as I am planning a high SCR NA redblock. I read a paper that the EPA produced in like 2002 where they were able to run a diesel passat engine on E85 by swapping in different injectors and replacing the glow plugs with spark plugs. IIRC the SCR on those engines is above 18:1
 
I know that most guys focus on turbos around this neck of the woods but....

what is the highest static CR someone has been able to get away with on E85? (and what kind of camshaft for the DCR)? This would be really helpful, as I am planning a high SCR NA redblock. I read a paper that the EPA produced in like 2002 where they were able to run a diesel passat engine on E85 by swapping in different injectors and replacing the glow plugs with spark plugs. IIRC the SCR on those engines is above 18:1
That is not impossible, but...

The shape of the head and the top of the piston has to be good or else it will not work.

I do not think you can actually make a 8v E85 car with 18-20:1 CR. 12-14 (maybe 15) is possible without any trouble though.

The 16v may be better suited for high CR.

And I think you need a cam that brigns down the DCR a bit since it would probably diesel at low rpm's.
 
Hello!

how can i count extra flow for:
E70 (70% of ethanol, 30% of gas)
E100 (100% ethanol)

Thank you!
 
Hello!

how can i count extra flow for:
E70 (70% of ethanol, 30% of gas)
E100 (100% ethanol)

Thank you!
OK. I'll try to put this in more common term for the ones that are not mathematical engineers like myself so that everyone can understand them and make use of it when applied to their car. I will use more common terms that will not seem cryptic.

Since the density of ethanol and gasoline is not the same (750kg/m3 for gasoline and 790kg/m3 for ethanol), the flow numbers will be off by a few percent when calculated with this easy formula that exludes the density. But it works fine for the sake of simplicity.

The volume of the resulting mix of fuels will not be the same either. If blending 1000cc of ethanol with 1000cc of gasoline you do not get 2000cc of fuel.

Then the viscosity is not the same either so an injector that has a specified flow for gasoline will not have the same flow for ethanol.

In the end the difference from the simple calculation compared to reality is around 2%.

To calculate the extra flow for any blend of ethanol and petrol:

Petrol, Lambda 1 = 14.7 AFR

Ethanol (E85), Lambda 1 = 9.765 AFR

Ethanol (E100), Lambda 1 = 9.0078 AFR


F1 = Gasoline AFR
F2 = Ethanol AFR
C1 = Gasoline content in %
C2 = Ethanol content in %


(F1*10000/((F2*C2)+(F1*C1)))-100​

= The percentual increase in injector size​


But usually you want to use injectors that have a little bit higher flow. This is because you should be able to use the cold start and acceleration enrichment in relation to the equivalence ratio in my table.​

Let's take a look at it again.​

Fuel ........................ AFRst ........ FARst ....... Equivalence Ratio ... Lambda
Gas stoich ................ 14.7 .......... 0.068 ................ 1 ................... 1
Gas max power rich .... 12.5 .......... 0.08 ................. 1.176 .............. 0.8503
Gas max power lean .... 13.23 ........ 0.0755 .............. 1.111 ............. 0.900
E85 stoich .................. 9.765 ....... 0.10235 ............ 1 ................... 1
E85 max power rich ...... 6.975 ....... 0.1434 .............. 1.40 ............... 0.7143
E85 max power lean ..... 8.4687 ...... 0.118 ............... 1.153 .............. 0.8673
E100 stoich ................ 9.0078 ...... 0.111 ............... 1 .................... 1
E100 max power rich .... 6.429 ........ 0.155 .............. 1.40 ................ 0.714
E100 max power lean .... 7.8 .... ...... 0.128 .............. 1.15 ................ 0.870​

What this means is this:​

Look at the blue numbers on both Gasoline and ethanol. Ethanol requires more fuel flow to get into the rich region, and therefore requires more fuel (percentual increase) at cold starts and when stabbing the throttle. Not much more than gasoline, but enough to maybe give driveability problems on some engines since they want to buck a little initially when the throttle is stabbed.​

Let's look at the red numbers. In practice this means that to go full rich on gasoline you will need an extra 17.6% of fuel over stoich AFR for gasoline. But on ethanol you will need an extra 40% of fuel over stoich AFR for ethanol.​

When using 42% bigger injectors which is the recommendation when going from gasoline to E85, the theory doesn't really add up and you should end up with a little bit too little enrichment when accelerating since the ECU will add 11.1-17.6% extra fuel. That is not enough fuel to enrich the mixture of ethanol which requires 15-40% extra fuel for enrichment.​

In reality though, you will be pretty spot on the good numbers since our ECU's always want to enrich a little bit more than neccesary.​

But it is still a good idea to use 10% larger injectors than calculated to make up for those situations when the ECU can not enrich properly.​
 
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I don't mean to nit-pick, but that statement makes absolutely no sense.
Yes it does.

When mixing one set of molecules with another set of molecules they will not take up as much space when blended as they do if they were separated.

You can easily do an experiment with ethanol and water. Use a good container which is marked very well. Pour in exactly one liter of water and one liter of ethanol and it will take up less space than two liters.

Look at this. It is the easiest explanation I could find on the net as of this time: http://chemed.chem.purdue.edu/demos/demosheets/15.1.html

Other liquids have a much greater effect on the volume change since the elements mix to form a totally different molecular structure.

I am a math/physics/chemical 2nd grade engineer as base (well... not so much chemical engineer actually, but it is a requirement). That is required to become a digital hardware engineer. You need to know how everything works around you before you can start to understand how theoretical physics and particles/energy works on a sub-atomic level.
 
I'm probably going to convert my new car to E85.
'87 745ti. Manual transmission. N/A pistons. 9.x:1 compression.
It'll likely get a 531 head with a basic port and a KG2T cam. Signs grooves and a thin HG.

I've got the general idea down, I've just got some questions about getting the best bang out of it.

I've done the math, and with current prices, switching to E85 and adding 30% more fuel will give me the same dollar/mile cost, save for a few hundredths of a cent.
Now, figure in the ability to advance timing more, and being able to cruise on the highway at a lower throttle level, it should be significantly beneficial.

Fuel delivery:
Would I be better going with a higher line pressure and a shorter pulse, for the idea of better atomization? My terminology is probably off, but I think you'll understand the question?

EMS:
My car is LH2.2
How much of a benefit would I see by converting to 2.4 and adding your chips? Enough to offset the cost/time involved?

Thanks for an ingenius writeup, and also for continuing the support!
 
threw a CEL light story

I posted already here. I wanted to try and run E85 in my 944T with Ford 3.8L CFI injectors "402".
It all went well while I was in town going under 50mph most of the time and a few minute test run on the highway at 65-70 mph.
Few days ago i had to go Denver (about 1 hr drive) and I filled up with E85 and off we went.

The car pulled fine, but by the end of the trip (about 70 miles) my air-fuel-ratio meter from Sunpro started showing that I'm running rich. I have only 10 LED bars on the meeter and it is hooked up the the o2 sensor wire.
So by the end of the trip it woudl stay on the rich bar (one before last).
Then I stopped and went on with our business.
When I come back and start the car (say, after 15 minutes) the AFR meter shows rich (last bar) and stays there with no throttle and I see CEL is on.
So i went nicely to the nearest filling station and added few gallons of 91 gas and unpluged the black battery cable for a while and it cleared cell and the rich LED move from the last bar to the one before last where it stayed on for the whole trip back (another 70 miles).
NO CEL showed up since then.
Also, the next day in town (under 50 mph speeds) the car would behave normally again.

I have a question here: is it a normal behavior? Will changing to bosch "400" injectors help me with this highway thing? Also why is my AFR meter showing rich like that.

I guess i'm not grasping all science of the process here.

1) thanks a bunch
2) sorry for that many words
 
Fuel delivery:
Would I be better going with a higher line pressure and a shorter pulse, for the idea of better atomization? My terminology is probably off, but I think you'll understand the question?
Better and bigger (more modern) injectors is by far much better than adding bigger (used) injectors and raising the line pressure.

EMS:
My car is LH2.2
How much of a benefit would I see by converting to 2.4 and adding your chips? Enough to offset the cost/time involved?
With LH2.4 your car would probably use less fuel due to its higher efficiency.

But...

You have LH2.2 so you can manually adjust the base ignition timing to a higher value if you want. That will give you both power and better fuel economy if done right.
 
Fredrik, been following the post with interest. Not much E85 in Australia but i just happen to live in proximity to one og the larget ethnaol production facilities in the country. I am just about to jump and just want to be certain that i dont screw it up I have 1992 B230F LH2.4 stock. Which are the injectors you recommend i should install to run on E85 with no other modifications.
 
Fredrik, been following the post with interest. Not much E85 in Australia but i just happen to live in proximity to one og the larget ethnaol production facilities in the country. I am just about to jump and just want to be certain that i dont screw it up I have 1992 B230F LH2.4 stock. Which are the injectors you recommend i should install to run on E85 with no other modifications.
Since I still am not 100% certain of the stock size of the injectors, it is a little bit hard. But something equivalent to stock turbo injectors will be very good.

Also talk to JW240. He has been running NA for a while with E85 and some mods.
 
Hello!

about cold starts.

anyone knows, are in stock flex-fuel cars used fuel or intake air heaters?

where can i see photos or schemes of this heaters?

thank you, sorry for bad english.
 
Hello!

about cold starts.

anyone knows, are in stock flex-fuel cars used fuel or intake air heaters?

where can i see photos or schemes of this heaters?

thank you, sorry for bad english.
A few of them use a heater for the fuel rail, but most of them just richen the mixture up a lot. It will not really be an issue until you get down to below -10 / -15 degrees Celsius or so.

It will however be harder to start when the temperature is around 0 degrees Celsius. But if your injectors are sized right, it will work fairly good.
 
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