Ok, attempted searching, but there are a lot of scrambled threads without much concrete info.

I have a solstice, but the same info will apply.

What does it take to run E85 on an otherwise stock LNF?

Fuel system?

Tuning?

Exhaust issues?

Sensors (I.e. GM stage 1?)

Let's discuss.

 

Stock fueling, 50/50 e85 is the most you can put out. AFter 400whp, you're hitting the max point of fueling with ethanol. You'll need cams fuel lobe to compensate the extra fuel needed etc.

Mostly tune related, you need a good tuner.

 

I'm built motor, BW 6258 on full E85. I have Pwerks 5th injector with stock cams. I also have 3 bars too. As far as tuning, just pick someone who knows what they are doing, that's going to be the most important part!

 

What do you mean by 50/50?

Good tuner is a must, that's a given. I already have a tuner lined up, but I'm asking questions both for my own benefit, and anyone that may be curious in the future.

Another point, are the power advantages of E85 going to compensate for the fueling limits? Not looking to add additional injectors, etc. I.e. Will E85 make enough power before running out of fuel vs. running premium on stock fueling to make it worthwhile?

 

So the 3bar map and upgraded maf are needed?

 

Yea you are going to want them when you start doing tuning, especially with e85

 

Upgraded MAF is not.

The 3bar maps are needed if you are running significant boost.

I think the big question is, what are your goals? Most people can get away with half 91/half E85 because their power goals don't go much beyond 330-350whp.

 

I'm only looking for 350ish. I've never been a POWAAAHH fiend, just want some extra punch.

I'd rather run either/or on the fuel. Not interested in mixing.

 

Yeah, Blazin said the factory sensors work, but it's easier with the bigger ones, and the factory sensors eventually burn up anyways. Cheap insurance to go 3bar.

 

Yeah the 3 bar sensors are cheap insurance. Just get the sensors and get the conversion connectors from Crate Engine Depot to make install very simple.

As for mixing, to each his own.

Two options.

Add upgraded fuel lobe cams and then go full e85 or you could run 91/93 but run higher boost.

For many, mixing is the cheapest, easiest option and honestly a touch safer because you don't need as much boost out of the stock turbo. If you are already planning E85 you will have the limitation of finding an e85 pump anyway, what's another 30 second transaction to pump half and half. Just make sure to run the tank down between refills and keep an eye on your fuel trims.

 

This is why I'm not interested in mixing. Fortunately I have access to a nearby e85 station, so I'm not worried.

With e85, will I really be pushing that much boost on the stock turbo? 350whp is not that crazy of a number. My instructions to the tuner usually follow along the lines of don't make power at the expense of reliability. If he only wants to push it to 320ish, I'm ok with that.

 

You will very quickly find the limitations of the stock fuel system on straight e85 even with the stock turbo. 3bar sensors aren't a must and the vehicle can be tuned over the pressure ceiling of 23.5psi without an issues, however is risky especially when trying to monitor and control large boost pressure spikes. Tuning for straight e85 on the stock fuel system is doable, you are just limited significantly more opposed to doing something like an e47 blend.

 

Injector seals are another thing. Not sure about the Solstices, but only 2010 LNF Cobalts came with the black ones which are E-85 friendly.

 

That's easy enough to check. Good tip, thanks!

 

My sig numbers are on the stock turbo on full E85 @ 26psi. But remember I am at a mile high so I actually need less fuel since the car never actually hits the hp/tq numbers, which are corrected for altitude.
You may run out of fuel at sea level.

 

With A good tuner you shouldn't have any problem running straight e85 on stock turbo. benefit of running e47 is if you are bigger turbo or you dont have the updated seals to run full e85. You do not need to have 3 bar sensonrs to run e85 at all. they only come into play when running more than 23.5 psi. im sure most of this was said

 

Without fueling mods I'd run E47. That's my plan come spring.

 

so completely stock hardware on the car? I think you'll be fine running straight E85, not sure you'll be able to see 350 wheel but it'll feel quick for sure. There's no way to know for sure if you'll have enough fuel until you have the tuner try though

 

Ramp the boost in very slowly or plan on watching your rail pressure drop like a rock along with IPW's and IDC's go through the roof. The tune will have to be significantly more conservative on e85 than on e47 on 100% stock fuel system... period (unless for example you're at a higher elevation such as colodude18 is). Because of that, you will not hit 350whp ESPECIALLY on a kappa.

 

That is how I have mine setup. It works well if you're into autocross or potentially road racing and you want to limit wheel spin and have the knock protection of E85. It still pulls hard on the highway (22psi/17 degrees of timing up top), but I agree you'll probably be closer to 300whp or less.

 

E47 on a bnr with the 5th injector and stock cams at like 25-27 psi should be fine correct?

 

Yep that would work just fine. I'm on e47 with my setup @ 26psi with only a 5th injector for additional fueling and I see zero rail pressure drop.

 

Excuse my ignorance, but doesn't it take MORE fuel to make the commanded torque input at higher altitudes? Thinner air = more boost = more effort (fuel) to make the same power equal to sea level.

I could be wrong, but I'm pretty sure that is relatively basic physics.

 

sub. good info from knowledgeable people!

 

Negative. Higher elevation requires less fuel demand due to lower barometric pressure and air density. Absolute pressure and gauge pressure at high altitudes vary significantly from that at sea level. Gauge pressure at 3000ft at say 25psi is actually only 260pka absolute as opposed to gauge pressure at sea level reading 25psi which is right around 275kpa. To produce the same absolute pressure at 3000ft you would need to push 290kpa or 27.5psi gauge pressure for the same flow at only 25psi at sea level.

So long and short of it, higher elevation requires the turbo to work much harder to produce the same flow. When you're talking a small turbo like the k04 it is very limiting due to it's inability to produce those pressures and maintain adequate flow, hence reducing the fueling loads significantly.