E-85 vs 91 octane vs racing fuel

[j930]

had a discussion last week with a family member who has a turbo charged sand rail and was asking the type of fuel he is running. He said he has been and a lot of his friends were running E-85 as its the equivalent of 105 - 110 octane depending on how it is mixed? Have any of you tried running E-85 through your cars? ANy one know of any pros or cons? we can buy race fuel here in Phoenix out of the pumps at a few stations and its 100 octane. but its around 6.00 a gallon last time i looked. E 85 was less than 87 octane last i checked. any thoughts?

[DSPTurtle]

Wait for Drmatera to respond. I have heard that E85 is corrosive to our older cars fuel systems but he has been running it for years...

[Jim2]

I can't speak with any experience about corrosion issues etc but something I overlooked is the burn rate of a fuel like E85 versus race gas. Cost per mile may be similar.

[j930]

from my google search, it did say that it typically requires bigger lines at the flow rates are much higher

[tom84930]

I'm using E85 in my recently rebuilt 3.5L turbo motor. Last Spring following an aggressive rebuild the engine was tuned on a Dynapack using 91, 100 and E85. On 91 it made 597 HP. On 100 it made 650 HP. And on E85 it made 733 HP. The only thing that changed on the dyno pulls was fuel. For a more complete picture of the engine and the dyno tuning, including torque numbers, go to "2010: An EFI Hot Rod Odyssey" on this forum.

In order to use E85, Chris Carroll of TurboKraft used newly developed larger teflon fuel lines, high performance fuel pumps and larger injectors. It's my understanding (and I may be wrong) that Nascar is now using E85 as fuel of choice. Also, it's my understanding (and again I may be wrong here) that the octane equivalent of E85 is in the 114-116 range. The dyno numbers would appear to suggest that's accurate. Lastly, it's my experience that the car burns 20-30% more E85 that dynosaur petrol.

[turbobrat930]

Figure 30 to 40% more fuel running E-85 as it has a lower BTU rating as the same amount of pump gas. So, bigger injectors that can handle the extra flow (and not run out of duty cycle) are a must, as well as a pump that can handle the fuel flow. I have been told (I dont assume its true), that the stock twin pumps for the CIS system dont provide adequate flow for a high HP E-85 system. But, to me it does seem logical, as the fuel pressure is really high (CIS) for a normal EFI system, which usually runs 40 to 50 PSI... As pressure increases, flow decreases....

E-85 is around 106 to 108 Octane, but the octane rating is only half the benefit for us turbo guys. The other part is the cooling effect of the Ethanol. So, more ignition advance and lower EGT's mean more fuel can be added and possibly a little higher boost pressure resulting in a power increase.

FYI... I am running ID1000 injectors (100Lb) at 43 PSI.... They will flow perfectly up to pressures nearing 100 PSI.... but I will never run that high a pressure ( I wont have a need to). I dont think I will ever see duty cycles over 85% with the power I expect to see on E-85. I have a friend of mine who made 2650 HP in a twin turbo small block running E-85. It also burns very, very clean......

[tom84930]

30 to 40% more fuel is a new one to me. Having driven my car with E85, there's no way I'm burning that much more of the stuff. And in all of the research we did before converting to E85, we never saw E85 consumption numbers that high. But, hey, everyone's welcome to their opinions. All I really care about is that the car makes 733HP at a boost level that won't grenade the motor. And at 2550lbs it accelerates like the proverbial scalded cat.

[Tippy]

Damnit! Another thing to do to my car!

[turbobrat930]

I agree. I was also thinking about 30% was about right to me... But, he is also in the 2500 to 2700 HP range, and is knocking on the door of 3000HP. It may be different at that levels.

You also should be VERY happy with your dyno results... A-MAZING!!!! If i can get close to that, I will be estatic.....

[xbmwguy]

darrin talked me into running e-85 and im never going back. i am running much more timing, the car is running much cooler and with no adj with boost at 2800 my 315s are lighting up. i told eddie bello i switched and wiyh a big grin he said you wont switch back.i will however be switcing out my stock lines and going to a single fuel pump,but like was mentiond before darrin has been doing it for some time now with no ill effects and its cheap

[j930]

so it sounds like to be safe you would want to change injectors/ pumps and lines to accommodate the e 85. Brian at Rarely l 8 rebuilt my WUR and Euro fuel Distributer, i now have the larger euro fuel lines but original injectors. do i dare try and run the E-85 or just be happy with the 91 i am running. also read that the E-85 might have some corrosive properties to it?

[Tippy]

This I'm liking.....

[drmatera]

I'm not sure I would run e85 on a CIS engine. First would be the issue of supply, seems CIS can only support around 420rwhp on fuel, take 30% from that and your down under 300 hp worth of fuel supply.

As for corrosive, haven't seen any evidence of that on my "stock pumps and line".

As for cost vs race fuel. E85 is cheaper no matter how you slice it. And you will see an increase in power just switching to e85, forget the fact that you can add boost and timing as well.

Another very good reason to go EFI

[j930]

any of you guys running race fuel in your cis fuel systems. like 100 octane? i guess the question is how much octane can you safely run in a euro fuel system?

[turbo owner]

[QUOTE=drmatera;6360313]I'm not sure I would run e85 on a CIS engine. First would be the issue of supply, seems CIS can only support around 420rwhp on fuel, take 30% from that and your down under 300 hp worth of fuel supply.

As for corrosive, haven't seen any evidence of that on my "stock pumps and line".



Check all of the aluminum parts, those are what will be affected.

[drmatera]

I have.. In fact my buddy has been running E85 in his turbocharged mustang cobra for over 5 years. He pulled the engine down for a refresh and examined all the aluminum parts including the fuel rails. Zero signs of anything wrong.

j930, race fuel is not hard on CIS parts until you get up to that C16 fuel. The Porsche manual says not to run fuels with alcohol in the CIS system...

[JFairman]

[QUOTE=Check all of the aluminum parts, those are what will be affected.[/QUOTE]

When you ditch CIS for EFI there isn't much of anything aluminum in the fuel system anymore. The fuel lines through the center tunnel are some kind of plastic and the fittings and tank are steel.

A bosch fuel pump shell and fuel filter casing are aluminum and depending what brand of EFI fuel pressure regulator or fuel rails you have I can't think of anything else aluminum. The Carrera fuel rails and FPR are all steel if using those.

The CIS lambda fuel head used from 1986 - 1994 on the turbo motors has rubber orings around the steel control plunger cylinder and in the small built in system fuel pressure regulator and the lambda fuel head is made of cast aluminum so E85 could eventually be a risk there.

[strokher racing]

I am wondering how a fuel safe fuel cell would hold up with the internal foam and bladder. Fuel safe did not have a solid answer at all for me

[ficke]

For us old timers we would just say "alcohol".
Now that you can by fuel with 85 percent of it at the pump, it will really change the "pump gas" category for racing.

[rsscotty]

Originally Posted by tom84930

In order to use E85, Chris Carroll of TurboKraft used newly developed larger teflon fuel lines, high performance fuel pumps and larger injectors. It's my understanding (and I may be wrong) that Nascar is now using E85 as fuel of choice. Also, it's my understanding (and again I may be wrong here) that the octane equivalent of E85 is in the 114-116 range. The dyno numbers would appear to suggest that's accurate. Lastly, it's my experience that the car burns 20-30% more E85 that dynosaur petrol.

Nascar is not using E85. They are using 85% race fuel with 15% ethanol.