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Re: E-85 Update [Re: MikeyT] #23731
04/15/06 06:35 PM
04/15/06 06:35 PM
Joined: Jan 2003
Posts: 6,389
nielsville, minn.
Q
quickd100 Offline OP
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quickd100  Offline OP
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Q

Joined: Jan 2003
Posts: 6,389
nielsville, minn.
MikeyT; I'd say a qualified yes. You could modify a 750 eddy for it but, you will run into problems you wouldn't have with a holley.
First problem, no one makes jets big enough that I'm aware of, you'd have to drill your's. To get your idle curcuit rich enough you'd have to drill the emulsion tubes in your boosters. If you go to far there isn't any going back unless you can solder the hole and redrill.
My 750 AFB #4327S test mule's emulsion tubes started out at .037 I increased them to .040 when I installed a 509 cam on gasoline to get it to idle. With E-85 I'd have to drill them to .043 to get it 35% richer over the .037 baseline. With a long duration cam it would be a bit more. Also you still would have to increase the squirter size and pump shot duration for your accelerator pump curcuit.
I'd do it to my carb if I had a spare 1407 eddy laying around but I hesitate to recomend it to someone else.
As much as I like AFB/AVS/TQ carbs there just aren't as many tuning parts available as there are for holleys.Dave

Re: E-85 Update [Re: quickd100] #23732
04/15/06 06:58 PM
04/15/06 06:58 PM
Joined: Jul 2004
Posts: 4,732
Watertown, WI
MikeyT Offline
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MikeyT  Offline
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Watertown, WI
Thanks Quickd100

Here are the detail specs on my engine

440 engine (9:1)
230/236 degree cam from comp with .491lift
headers
750 Edlebrodck carb
edelbrock performer intake

Is this still too long a throw of a cam to run it? Also what size/style holley would you recomend to run e85?

thank you again for your help.
Mike


1969 Dodge Dart Swinger
Re: E-85 Update [Re: MikeyT] #23733
04/15/06 08:15 PM
04/15/06 08:15 PM
Joined: Jan 2003
Posts: 6,389
nielsville, minn.
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quickd100 Offline OP
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quickd100  Offline OP
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nielsville, minn.
First let me stress I'm no carb expert. If it was my motor and was going to run E-85 though i'd increase the compression first thing. You have to remember, E-85 has less BTU's per gallon than gasoline. It's high octane fuel and will like more compression which will offset some of the loss.
The 750 double pumper carb would be tough to beat. Also I would HIGHLY recomend a LM-1 meter, it will speed the tuning process and keep you out of trouble.
IMO E-85 will be becoming more common all around the country in the next couple years. Currently Holley and the other big carb companies haven't done any work with E-85. I think you will see this changing as they get more calls about it.Dave

Re: E-85 Update [Re: quickd100] #23734
04/15/06 11:47 PM
04/15/06 11:47 PM
Joined: Jan 2003
Posts: 3,504
DFW
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mr_340 Offline
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DFW
All of the common alcohols have lower heating values than gasoline components. So does nitromethane for that matter. The power gains come from the fact that you can put more fuel in the cylinder since the A/F ratio is lower.

Fuel Heating Value (BTU/lb higher) Stoich. A/F

Toluene 18,245 13.5
Iso-Octane 20,556 15.1
Methanol 9,770 6.4
Ethanol 12,780 9.0
Nitromethane 5,160 1.7

An approximation to the power potential (my terminology, not from the engineering text books) of the fuel is to divide the heating value by the A/F ratio. I'm a little fuzzy on all this since I took a class in college on internal combustion engines twenty years ago. I think it's pretty close to what is right.

Fuel Heating Value / Stoich. A/F = Power Potential

Toluene 18,245 / 13.5 = 1351
Iso-Octane 20,556 / 15.1 = 1361
Methanol 9,770 / 6.4 = 1527
Ethanol 12,780 / 9.0 = 1420
Nitromethane 5,160 / 1.7 = 3035

I think from this you can see why methanol makes more power than gasoline. And it should really be obvious that nitro will make twice as much power as methanol (assuming you could run 100% nitro).

I don't think the octane rating is as great as you seem to think, but results are results. The difference between the RON and MON octane numbers gives the SENSITIVITY of the fuel to changes in load, speed and temperature.

Fuel RON MON Sensitivity

Toluene 120 109 11
Iso-Octane 100 100 0
Methanol 106 92 14
Ethanol 107 89 18
Nitromethane not rated, but probably close to zero

I know guys that run methanol in their dirt track Shivies and they run less timing than with race gasoline. I think this is due to a relatively low octane rating, particularly the MON numbers which is the more severe test and gives a lower number accordingly for most fuels. I'd watch for signs of detonation closely if it was my engine. But for pump fuel, it's better than the 93 premium.

QuickD100: let me know how the optimum timing is for E85 vs. race gas if you have the data. I'd be interested in your test results.



Floyd Lippencott IV
Re: E-85 Update [Re: mr_340] #23735
04/16/06 10:30 PM
04/16/06 10:30 PM
Joined: Feb 2003
Posts: 752
North Dakota
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Jesse_Lackman Offline
super gas
Jesse_Lackman  Offline
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Joined: Feb 2003
Posts: 752
North Dakota
Quote:

The power gains come from the fact that you can put more fuel in the cylinder since the A/F ratio is lower.




The reason you can put more E-85 fuel in (richer) is because the fuel is oxygenated, its oxygen content is higher than that of gasoline.

That is where the power increase comes from, more oxygen and the fuel to go with it = more power.

There is a power increase at the same CR, icing on the cake is its 100+ octane rating which allows a CR increase for an even bigger power increase.

Here in ND it has all the normal road tax on it.

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