Dual quad e85

[j par]

And now a personal record a triple post LOL...

 

[70aarcuda]

yes we have been using it for numerous years on 3 cars......only have had a few problems ...but mostly my lack of attention...
But we used QFT 950s that were are E85 carbs....

 

[j par]

yes we have been using it for numerous years on 3 cars......only have had a few problems ...but mostly my lack of attention...
But we used QFT 950s that were are E85 carbs....

I'm willing to spend the 50 bucks on a bunch of jets and metering rods and a couple gallons of E85 and see what happens on my wideband? Who knows maybe with all that extra carburation I have will get me lucky. I was thinking again running one to one with the two carburetors getting the double pump shot. Or maybe I'm missing something completely?

 

[AJ/FormS]

I've been thinking about this,a little.....
If your,engine or any engine, can pull 800cfm, then it doesn't or shouldn't matter if you do it with 4 barrels,six or eight , the engine combo can only pull 800.
So say you run 2x4 carbs and they're gonna flow about 400 apiece. It won't matter if they're 400s or 500s or 650s, the engine can only pull 800.
So now your job is to get the right amount of fuel thru those two.
Theoretically, in my head, you now have double the amount of jets to get the job done. And E85 requires almost double the amount of fuel. So again, in my head, if you upjetted those bad-boys to standard jetting, wouldn't that make the numbers or close to it? So that would take care of the WOT AFR.
Then come the headaches
So logic tells me you are on the right track, but I don't I know anything about E85... I'm Just thinking

 

[JBurch]

I've been thinking about this,a little.....
If your,engine or any engine, can pull 800cfm, then it doesn't or shouldn't matter if you do it with 4 barrels,six or eight , the engine combo can only pull 800.
So say you run 2x4 carbs and they're gonna flow about 400 apiece. It won't matter if they're 400s or 500s or 650s, the engine can only pull 800.
So now your job is to get the right amount of fuel thru those two.
Theoretically, in my head, you now have double the amount of jets to get the job done. And E85 requires almost double the amount of fuel. So again, in my head, if you upjetted those bad-boys to standard jetting, wouldn't that make the numbers or close to it? So that would take care of the WOT AFR.
Then come the headaches
So logic tells me you are on the right track, but I don't I know anything about E85... I'm Just thinking

In the simplest terms, the required added volume of fuel required when going to E85/Alcohol has to do with BTU per pound.........for the sake of argument, lets say that 1 pound of gas has 10,000 BTU, to reach the same number of BTU, it takes 1 1/2 pounds of alcohol. Alcohol has it's own air fuel ratio, don't know what it is, but it is different than gasoline.

 

[j par]

I've been thinking about this,a little.....
If your,engine or any engine, can pull 800cfm, then it doesn't or shouldn't matter if you do it with 4 barrels,six or eight , the engine combo can only pull 800.
So say you run 2x4 carbs and they're gonna flow about 400 apiece. It won't matter if they're 400s or 500s or 650s, the engine can only pull 800.
So now your job is to get the right amount of fuel thru those two.
Theoretically, in my head, you now have double the amount of jets to get the job done. And E85 requires almost double the amount of fuel. So again, in my head, if you upjetted those bad-boys to standard jetting, wouldn't that make the numbers or close to it? So that would take care of the WOT AFR.
Then come the headaches
So logic tells me you are on the right track, but I don't I know anything about E85... I'm Just thinking

Same thing I'm thinking that's why I keep asking what am I missing?

 

[JBurch]

Same thing I'm thinking that's why I keep asking what am I missing?

You are missing the difference in BTU per pound of the 2 different fuels and the energy that is available..............

 

[AJ/FormS]

Same thing I'm thinking that's why I keep asking what am I missing?

Getting it done?,lol
Pave the way for me, except I'm keeping my 230cam

I think pure ethanol is 9/1 WOT
pure methanol IIRC was 7/1 WOT

 

[fishmens67]

corn whisky burns cool, although it goes down smooth.

 

[Cudafever]

The e-85 is not going to like your deedle and seats and your rubber hoses. Probably won't matter much for a test run, but you will need to think about the hole fuel system.
If you have to double the jet side(and i don't know) then you will have to double the fuel pump and supply, may need larger needle and seats to get the flow into the carbs. Remember, the holleys have two needles and seat per carb. you have one per carb.
Just some thoughts.

 

[yellow rose]

I've been thinking about this,a little.....
If your,engine or any engine, can pull 800cfm, then it doesn't or shouldn't matter if you do it with 4 barrels,six or eight , the engine combo can only pull 800.
So say you run 2x4 carbs and they're gonna flow about 400 apiece. It won't matter if they're 400s or 500s or 650s, the engine can only pull 800.
So now your job is to get the right amount of fuel thru those two.
Theoretically, in my head, you now have double the amount of jets to get the job done. And E85 requires almost double the amount of fuel. So again, in my head, if you upjetted those bad-boys to standard jetting, wouldn't that make the numbers or close to it? So that would take care of the WOT AFR.
Then come the headaches
So logic tells me you are on the right track, but I don't I know anything about E85... I'm Just thinking

That's a simplified way of looking at it, but the math doesn't work out.
When alcohol became all the rage, I looked extensively into alcohol carbs. At that time, most guys were running 650 cfm carbs, because any more air flow and you couldn't get enough fuel through the needle and seats, let alone through the internal passages that feed the mains and idle circuit.

Now you can buy the parts with enough internal passage volume to get the job done.

That may be the limit of what jpar wants to do. I haven't been inside an AFB style carb since probably 1985. I'm not sure how big you can make the internal passages, or if you even have access to enlarge the passages.

He would be doubling the jet area, doubling the bleed area etc. But...not by enlarging the internal passages and needle and seats, but by having double the pieces.

It takes 2.2-2.5 times the amount of alcohol to make the same power as gasoline. Thats the math. I would assume E-85 would take roughly 85% of the amount of fuel that methanol takes.

Now that I typed all that...disregard all of the math. I never burned ethanol so I'm not sure it's the same amount of fuel as methanol. But it has to be close and I'm not pulling out my book to check the BTU's of ethanol.

 

[flyfish]

I don't know anything about running e85 in an Edelbrock carb, my home built carb is Holley based....with that said, you will need to make accommodations for ~40% more fuel. e85 will not work with paper fuel filters, so get rid of those (use steel mesh). Yellow Rose hit one of my main thoughts....the needle & seat and internal passages need to be larger to accommodate more flow...not sure how that would work with an Edelbrock carb.

For grins, giggles, and math nerds....BTU energy, gas is ~114,000, ethanol is ~76,000, and Methanol is ~57,000. e85 falls between gas and ethanol (obviously since it is 85% ethanol and 15% gasoline) at ~82,000. This is why you need to burn ~30-40% more e85 to make the same power as gasoline.

From a stochiometric perspective, I have found e85 to be more forgiving (i.e. you don't have to have the jetting perfect) and more consistent than gas when running throughout the day.

...and I agree to all those that said it....e85 STINKS...Race fuel smells sooo much better, BUT e85 is cheap, runs cooler, and my car runs faster on it than regular gas. Results may vary, but everyone I have talked to picked up at least a tenth over gas (I picked up ~2 tenths).