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Discussion Starter #1
I can't seem to find the answer Im looking for. I have a direct port kit I am going to install, I assume I some how have to jet it richer then what it would be if I was on pump 93, right?

Also would it be better to just build a 1 gal or 2 fuel system just for the direct port and run 93 in it?
 

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Discussion Starter #3 (Edited)
Yes you have to just run a larger jet then normal. I was just talking to my tuner about this.
So should I run the next size jet on the fuel side?

I have 3 shots, 120, 150, 200; so if I run a 120 shot should I run the fuel jet for the 150 on it?

Edit my fuel set up is going to be a -6 line from the gas tank to the fuel rail, and a single Walbro 400.
 

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1.8 nawz powa
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The easiest way for me to explain it is e85 needs about 40% more fuel to burn so run a jet 40% larger then the "normal" for 91 or 93 fuel. The fuel pump may play a small part.
 

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1.8 nawz powa
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I wouldn't say a problem, but be a pain cause the mixture of fuel will change once nitrous was engaged which would ruin the whole reason of going e85 to begin with. You would pretty much have a tune on nitrous and one off, just have the e85/93 mixture tuned. The whole reason to run e85 is because it burns cooler and with the octane close to 105.
 

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Discussion Starter #7
I wouldn't say a problem, but be a pain cause the mixture of fuel will change once nitrous was engaged which would ruin the whole reason of going e85 to begin with. You would pretty much have a tune on nitrous and one off, just have the e85/93 mixture tuned. The whole reason to run e85 is because it burns cooler and with the octane close to 105.
You are 100% right, which is why I thought jetting it for e85 would be a better idea. 600hp her I come!
 

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Aaaahhhh makes sense now.... with that said, just run a 150 fuel jet worse case is she runs rich, then adjust if need be. But that's just me, it seems less of a headache..
 

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I wouldn't say a problem, but be a pain cause the mixture of fuel will change once nitrous was engaged which would ruin the whole reason of going e85 to begin with. You would pretty much have a tune on nitrous and one off, just have the e85/93 mixture tuned. The whole reason to run e85 is because it burns cooler and with the octane close to 105.
if you mix e85 with 93 the effective octane rating will lower, and you would have to mix it consistently each time to have your tune right, or you will have to retune each fill...

the only issue ive had with e85 was cold start, i mean in 30-40*F range it took a while to start. if you live in an area that gets cold, have it tuned for cold start too, it will need to add more fuel, because the ethanol needs to be warm to ignite properly.

it runs cooler because the latent heat of vaporization is lower. you can actually touch your intake manifold after the car has warmed up and it feels cool or slightly warm..

the one question that has been on my mind was the thermostat. could you put a "hotter" thermostat in?

and for the nos kit, couldn't you use a lower shot to achieve same goal
because ethanol releases oxygen when its burned?
 

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Alcohol does not release oxygen when it burns. It just takes less oxygen to fully burn it as it is already partly burnt in effect by the oxygen it contains.
 

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Using 93 octane as the enrichment fuel in a nitrous system will lower the overall octane when you most need a higher octane. I think that is a really bad idea.

To correct from petrol to E85 you need to increase the jet cross sectional area by the difference in stoich for each fuel.

Stoich for petrol is 14.7:1

Stoich for ethanol is 9:1

Stoich for 15% petrol 85% ethanol mix is (14.7 X 0.85) + (9 X 0.15) = 9.85

To correct a jet from petrol to E85 that is an 85:15 blend you take the Cross Sectional Area (CSA) of the petrol jet 14.7:9.85. To do that you divide the CSA by 9.85, then multiply that number by 14.7. CSA of a jet does not change directly with diameter. For instance if you double the dia, you increase CSA by about 4. Think of it this way. If you have a 1" pipe. You increase it to 2". Not allowing for wall thickness, you can fit 2 by 1" pipes inside a 2" pipe and have a bunch of room to spare.

To calculate the CSA of a jet, you use the formula of Pi X R X R, or you take the diameter (drill size it was made with) divide the dia by 2 to get the radius, You multiply the radius by itself to get the square, then multiply that by Pi or 3.1416 to get the CSA

Say for example the jet is 0.060"

0,060/2 = 0.030.
0.030 X 0,030 = 0.0009
0.0009 X 3.1416 + 0.00283

Now to correct that jet from petrol to E85

(0.00283/9.85) X 14.7 = 0,00422 CSA required

This presumes that your E85 is ALWAYS 85:15 ethanol : petrol. This is not always the case and so called E85 can be as low as 70:30 ethanol : petrol in a winter blend in a cold area. This is to make for easier cold starting. You need to ensure your fuel is a consistent blend or you need to adjust your tune to correct for the different blend.
 

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A hotter t-stat doesn't help when the car is dead cold. Alcohol is BAD fuel in winter, when it is the majority of what's in the tank.
i do not mean for cold start. i mean for general driving. will it help at all for overall perfomance and fuel economy.

say for instance you run with open t-stat all the time on gasoline, and if you dont overheat while running t-stat open all the time, the engine will run too cold thus ecu will try and add more fuel if its cold.

the reason i say dont overheat from running open t-stat or no t-stat at all is because if the fluid is moving too quickly through the system, it will not have enough chance to transfer heat and continue to warm up.

Alcohol does not release oxygen when it burns. It just takes less oxygen to fully burn it as it is already partly burnt in effect by the oxygen it contains.
I mean that ethanol contains 35% oxygen to begin with which is far higher than gasoline.

if you try inject the same amount of fuel(ethanol or gasoline) it will burn very lean

hence it needs 20-40% more fuel/spark to be functional.
 

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i do not mean for cold start. i mean for general driving. will it help at all for overall perfomance and fuel economy.

Not really. If the stock thermostat was to cold it might, but the stock thermostat is already quite hot. If it helps anything it might help fuel economy a very small amount.

say for instance you run with open t-stat all the time on gasoline, and if you dont overheat while running t-stat open all the time, the engine will run too cold thus ecu will try and add more fuel if its cold.

This is just plain wrong. The thermostat stays closed until a certain temperature is reached, then as heat increases the thermostat progressivly opens, no matter what fuel. It won't open until the engine is warm enough.

the reason i say dont overheat from running open t-stat or no t-stat at all is because if the fluid is moving too quickly through the system, it will not have enough chance to transfer heat and continue to warm up.

Completer bunkum. By that logic, if the water passes through the block to fast to pick up heat, it also passes through the radiator to fast to shed heat. Removing a thermostat harms the engine because it can run to cold for to long, not because it causes it to overheat.

I mean that ethanol contains 35% oxygen to begin with which is far higher than gasoline.

UMMMMMM, traditional gasoline contains no oxygen at all, so I guess you could say 35% oxygen is a lot more. See my rather long post yesterday that quantifies that.

if you try inject the same amount of fuel(ethanol or gasoline) it will burn very lean

UMMMM yea see above.

hence it needs 20-40% more fuel/spark to be functional.

UMMMM no. Pure ethanol needs 37% more fuel. See examples of calculations I posted yesterday. Spark has nothing to do with this. A change to spark timing is dependent on the burn rate, not the oxygen content.
 

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()*#$(*$
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heh

What Pat said.

To add to that, if you tune the ECU correctly with proper IAT and ECT corrections, you will be able to keep the car fairly consistent. no matter what the temps are. So . . . No. I'd have to say you were wrong on just about all accounts.

I think you should look at the chemical structure of ethanol. The oxygen is not a "free" oxygen molecule. It is part of an OH group that is bonded rather strongly to to what would otherwise be an Ethane molecule (hence the name "ethanol"). It does not want to react with the molecular oxygen in the air at all. It would rather react with hydrogen to form water.
 

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the block would have the chance to overheat moving fluid too fast, it will heat the radiator and wont have enough time to shed the heat.
water is rather insulating, so if you heat it, it doesnt want to give the heat away easily. the thermal conductance of water is higher than aluminum

try it and come back then...

i know how a thermostat works,what i ment was if it ran open( either stuck open or removed)

heh

What Pat said.

To add to that, if you tune the ECU correctly with proper IAT and ECT corrections, you will be able to keep the car fairly consistent. no matter what the temps are. So . . . No. I'd have to say you were wrong on just about all accounts.

I think you should look at the chemical structure of ethanol. The oxygen is not a "free" oxygen molecule. It is part of an OH group that is bonded rather strongly to to what would otherwise be an Ethane molecule (hence the name "ethanol"). It does not want to react with the molecular oxygen in the air at all. It would rather react with hydrogen to form water.
the equation for the ethanol reaction during a burn
is C2H5OH + 3O2---> 2Co2 + 3H2O

shit dont just come together like magic... oxygen wont bond to carbon without a reaction.
if you put carbon in an oxygen environment does CO2 just magically happen? no.
ethanol is ethanol because of the c2h5 which is part of an ethyl group.
 

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SOHCpower

I am not about to risk my engine life because your stupid. You try it and come back. I already know the result from seeing other stupid or ignorant people try it.

Re ethanol burning, gee wizz, none of us did high school chemistry. Also, I thought maybe the OH group was the significant one in distinguishing alcohols from aliphatic hydrocarbons. If you use big words to try to prove your smart, be careful you know what they mean, otherwise you just prove your really incurably stupid.
 
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