E85 fuel consumption compared to 91 or race gas

JM PRO

JM PRO

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Okay GD.COM peeps,

I have a Subaru 2.5 460HP tuned on race gas and want to convert it to E85. I roughly burn 4 gallons of fuel per run now on race gas. How much additional fuel consumption should I figure on after converting to E85? Also, can I expect a increase in power after a new tune or will the engine remain at the 460HP level?

Thanks

 
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I am pretty sure you will gain power run cooler and use roughly 20% more fuel.  So like 6 gallons per run vs 4 gallons 

 
I switched to E85 last season on my LS2 with super charger but never calculated my exact new fuel consumption but was told rule of thumb is to expect 30% more usage.  I did gain more HP and the engine does run cooler.  I ran out of fuel on my very first dune trip so I just refuel every time we get back to camp.

 
 E85 motors love tons of extra fuel. It’s not uncommon for a tuner to add 50% more fuel because the car keeps making power. Also, make sure your tank is completely empty and use the local Arco fuel without any additives for the tune. The only additive I ever use after is the Lucas E85 stabilizer. I put 1 bottle per drum. I ran out of fuel last season and had to buy a drum of the expensive x85 and I saw no gain other than it smelling a little better. 

 
Test your pump gas E85.  I didnt see much change last season from stations in Orange County. 80-90% is what I saw.  This is a new season and who knows whats happening with the fuel prices and the quality.

I averaged 6 -8 gallons a run but your mileage may vary.  E85 is much cheaper and easier for me to get.

 
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About 20-30% more fuel for me.

I needed bigger injectors going to E85. 

Also had to switch all my fuel lines to e85 safe. Started having issues with the injectors clogging. New fuel lines and injectors and all was good.

 
I run e85 in my Honda 3.5 turbo, I think an average dune run is in the 8 gallon range.  I have no problem duning from Cement Flats to Flag pole, to China Wall, to Olds, to vendors and then back to Cement Flats.  I would guess that would be close to 10 gallons.  And this is duning the whole way, not straight lining.

 
Rule of thumb is 30% More for SAME POWER based on the "math" as others have stated.

However with a boosted car you can up the timing and the Boost ands still be "safe"  and if you are smart you will take advantage of it

SO - Most people see it closer to 50% because they tune to take advantage of the superior cooling effect of E85.

On the Holley systems I have done, I use a Flex Fuel Sensor and it "automagically" adjusted the Boost and timing based on the amount of Ethanol in the fuel - this means as Grease Monkey said you can "test" the fuel and "most" propel stations around here are consistent between E85 and E80 , but I hear some stations can be E70.

But this does not affect the amount used.

Bottomline Race to E85 - no changes   ~30% more used

Practical take advantage of the benefits of E85 ~50% more used

 
My LS7 440 burns 20% more on E85.  Typically extra 1 to 2 gallons per ride.  

 
my car i had a oldschool 406 small block chevy in it, built pretty rowdy na. i ran e85 form the start so i dont know the usage differance from race gas. now i built this engine from parts used from a prior 383 i had in a drag car, heads, intake and camshaft were from the 383.  the 383 used approx 3 gallons for a 1/4 mile pass which included driving to staging from pit, burnout, run, and back to pit. in the sandcar i had a 32g cell.. i could not make it to duners diner and back from pad 3 in one tank on e85.

so new engine im putting together is a twin turbo ls, small cid. planning on pump gas most of the time, but i am setting it up to run e85 as well and have a flex fuel sensor, etc. for when i want to turn up the boost to level 11.. lol

 
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