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ME Bloodhound
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More injector and a tune is minimum. Gotta find out how much the pump can take. Other than that i don't see it needing too much more. The 5.0 only need injectors and a tune, but thats N/A.
 

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You won't need injectors on a ecoboost. As the stock fuel system has already shown amazing potential.
A tune is all that should be needed



?and ? fed coyote.
 

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The good thing about Direct injection is that E85 has an effective octane of about 160.

What this means, is that you can get the same knock suppression with as little as about 25% E85 per tank as you could with 100%. I was doing some testing on my last car, big turbo, making about 400 whp and went down to as little as 2 gallons of e85 per (16 gallon) tank before i started seeing slight bits of knock. 4 gallons of E85 in a 16 gallon tank (so 12:4) only increases your fueling needs by about 10% all else equal. For that reason, you will 100% need a tune to run E85, as well as the specific gravity of the fuel needing to be adjusted (this basically helps your fuel trims keep your fuel targets on point).

In fact, the less E85 you use, the more power you will make, you only want to use enough E85 to suppress the knock. The only reason tuners do not tune for blends is because they cant trust people to not screw up their fill ups, so its 100% or nothing.

Assuming you are not knock limited, you will actually make the most power with 93 and methanol since there is the most BTU available, but most people run E85 because it is cheap as dirt and a part of the factory fuel system, not an auxiliary system. Here's some math i ran for a customer a while back when i had to explain why he was making more power on 93 and meth than when he wanted to switch to E85. I'm not saying E85 is bad, its basically God's gift to the racecar, but check this out anyways:


Methanol: 56,800 BTU/Gal
E85: 81,800 BTU/Gal
Gasoline: 114,600 BTU/Gal

So, using our 25% E85 blend, we basically get an effective BTU of 106,400 / gal.
(81,800 *4/16) + (114,600*12/16) = 106,400 BTU for a 25% E85 or about 30% ethanol per tank.

Next, if we inject methanol into that same 25% E85 blend.
3400 cc/min total @ 85% IDC gives us ~2890 cc/min from the stock fuel system, or 45.80 GPH.
The Meth gave us ~10.05 GPH, assuming we used ~75% of a 14 gph nozzle.
82% of our fueling was stock injectors, and 18% was methanol.

Heres where it gets really fun. We were still spraying a 25% E85 blend through the stock injectors at that point, so we had an effective BTU of 106,400 as listed above.
106,400 * .82 = 87,248
56,800 * .18 = 10,224
Effective BTU when we had the E85 and meth was 97,472

... i was hoping to prove the meth + E85 blend had more effective BTU, but it seems it was just the opposite since the E85 gets diluted with the methanol... Interesting.

Heres a real doozie ... Straight 93 with meth gives you 104,196 BTU/gal o_O

114,600 * .82 = 93,972
56,800 * .18 = 10,224
Total = 104,196

Obviously this isnt taking things into account like knock suppression or things like that, but basically you have a "higher power potential" with 93 and meth than you do with all 3? Strange indeed ...
 

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Discussion Starter · #10 · (Edited)
i would love to run 93octane but im in California and we only have 91 pump...how ever there is a place with 100octane on pump but its 9$ a gallon. plus that would also call for a tune and maybe burn up the cats.

Sent from my LG-D415 using Mustang Evolution mobile app
 

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100 octane, assuming its unleaded, would neither "need" a tune, nor damage the cats. The reason i put need in quotations, is because you could run it, but may not see much of a performance gain from it, without a tune.

That being said, if you did 25% blend of 100 octane (12 gallons 91 and 4 gallons 100 per tank) it balances out to right about 93.5 octane lol ...
 

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Obviously this isnt taking things into account like knock suppression or things like that, but basically you have a "higher power potential" with 93 and meth than you do with all 3? Strange indeed ...

I agree, benefits per volume when ethanol is added is a sq root function meaning around 30% volume the benefits start to max out on octane rating while also decreasing energy content. With a DI injected motor running 30-85 percent alcohol fuel such as E85 the increase in compression or boost its capable of due to new heat of vapourisation is staggering. The expansion rates are also much higher reducing heat transfer losses, maximising thermal efficiency.
So I run my engine at 14:1 CR and use flex fuel 30-85 percent alcohol mainly because I wanted to take advantage of the high latent heat of vapourisation and better thermal efficiency under high compression across a broader range of operating conditions. Gasoline is around 390 kJ/kg and ethanol 900 kJ/kg for heat of vapourisation, and hydrous e85 (ethanol with good licks 5-10% water in it) has 2260 kJ/kg from H2O. This is an unbelievable benefit.
So measuring heat energy of fuel in BTUs does not equal power in an ICE, rather in an Otto Cycle efficiency increases with the compression ratio, which is limited by the need to prevent the uncontrolled combustion.
Higher ethanol fraction under high compression produces higher IMEP and ITE and ISFC than 93 and meth.
My DD car is a 370cid NA Port Injected two valve per chamber cam in block V8 with 610bhp and returns 27.5mpg on e85.
My point is that lower compression engines make better use of gasoline and meth, sure, however e85 will always outperform anything at the pump with increasing effective pressure.
 

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I agree, benefits per volume when ethanol is added is a sq root function meaning around 30% volume the benefits start to max out on octane rating while also decreasing energy content. With a DI injected motor running 30-85 percent alcohol fuel such as E85 the increase in compression or boost its capable of due to new heat of vapourisation is staggering. The expansion rates are also much higher reducing heat transfer losses, maximising thermal efficiency.
So I run my engine at 14:1 CR and use flex fuel 30-85 percent alcohol mainly because I wanted to take advantage of the high latent heat of vapourisation and better thermal efficiency under high compression across a broader range of operating conditions. Gasoline is around 390 kJ/kg and ethanol 900 kJ/kg for heat of vapourisation, and hydrous e85 (ethanol with good licks 5-10% water in it) has 2260 kJ/kg from H2O. This is an unbelievable benefit.
So measuring heat energy of fuel in BTUs does not equal power in an ICE, rather in an Otto Cycle efficiency increases with the compression ratio, which is limited by the need to prevent the uncontrolled combustion.
Higher ethanol fraction under high compression produces higher IMEP and ITE and ISFC than 93 and meth.
My DD car is a 370cid NA Port Injected two valve per chamber cam in block V8 with 610bhp and returns 27.5mpg on e85.
My point is that lower compression engines make better use of gasoline and meth, sure, however e85 will always outperform anything at the pump with increasing effective pressure.
im going to have to read that 2 or 3 more times for it to really sink it, but it sounds convincing haha.
 
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