JohnnyLS7

Good Morning fellow members! I was considering on doing the conversion on E85 from gas. I have been told it is very beneficial to boosted cars. I have a 2007 Z06 Supercharged and i am running meth injection. I am doing some research and i'm seeing on these forums that most people are saying all you need is injectors and a tune, however i have been told by a few people that you actually need fuel pumps and fuel lines as well due to E85 is pushing more volume than gas. I also would like to add that i need to be able to use pump gas on occasion due to a future road trip i am setting up across the country. I was told they have a flex fuel sensor that allows this magic to happen but someone told me it isn't too reliable or its not 100%.... lastly, i'm hearing craziness that you have to test the E85 with a test kit to see how pure it is???? Is all this true??? Seems very involved and i would like to get the facts straight! I know coming here and talking to all you great people will get that accomplished... the forums are AWESOME for info!!! Thank you all in advance!!!!

Johnny LS7

Unreal

Do a flex fuel setup. They are in most modern cars warrantied for 100k+ miles, so I wouldn't worry about reliability.

Depends on the power you are making what fuel system you need. Since it supercharged I assume atleast 600rwhp which means you need to build a fuel system for 25-30% more than that to support it on e85. So you need a system that will support 800+ on gas, which means pumps/injectors/etc. At least a dual AEM 320 e85 compatable system from fore, but might as well do the triple in case you turn it up later.

Streetk14

With a flex-fuel sensor setup and proper tuning, you shouldn't need to worry about the ethanol % of the E85 you buy. The beauty of having that sensor is that you can switch from E85 to pump gas at will. Contact Dave Steck if you need info on the system he builds and sells.

If you already run meth, I'm not sure how much of a benefit you'll really see with E85. You might be able to run some more timing or boost, but there are the downsides of E85 that you need to consider. The main one for the C6 being major fuel system improvements to support the extra fuel volume.

You're likely looking at new injectors, a new fuel system, the flex-fuel kit and related tuning to make it happen. Unless you have a really extreme setup, I don't really think it'll be worth it.

Milan

You can make a noticeable amount more power over pump gas + meth.

E85 > race gas > pump + meth > pump

JohnnyLS7

Thank You guys for the info... greatly appreciated. I am not looking to make more power but i would like to get rid of the METH injection. I have heard lots of horror stories to failed pumps and i dont want that to happen to me. So im seeing the benefit of E85 is it will keep my motor safer with the high octane and its cheaper than gas... almost by a $1 where i live in NY.

Streetk14

E85 is cheaper, but your gas mileage takes a big hit with it. With a stoich value of less than 10:1, you can probably see why. It requires a greater volume of fuel at all times vs. pump gas.

If you want to ditch the meth, then it's just about your only other option short of running race gas all the time. Just keep in mind that whatever possible reliability issues you might get rid of with the meth might come back in other ways with an E85 setup. You're taking away one possible failure point, but you're adding others (aftermarket pump or multiple pumps that can fail, aftermarket fuel system BS, etc.).

I'm also not sure how good of a plan the E85 thing is if you want to run regular pump gas sometimes. If you're boost level and compression requires meth to run a reasonable amount of timing, then it's going to need to be tuned really conservative timing on regular pump gas. This usually isn't a great thing for an engine. Sure, being able to run pump gas in a pinch is great -- but I wouldn't be out beating on the car like that.

My 2 cents anyway.

Streetk14

I should also mention that I'm not an anti E85 guy. I run an E85 blend in my turbo BMW at all times, but the stock fuel system and closed-loop WOT engine control allows it with minor tuning. For that car, it's the best thing since sliced bread.

I've been debating going E85 or meth on my new C6 project. Whichever way I go, I'll probably be using Dave's flex-fuel module. : http://forums.corvetteforum.com/c6-f...t-details.html

I haven't tried this myself, but looks like a great way to safely tune for meth and prevent any catastrophic failure if the system fails.

Unreal

You can? I haven't seen it on an LS platform. E85 or pump+meth always seem to be motor or power adder limited, not octane limited.

Also I completely disagree with e85>race gas. c16, q16, vp import, etc are all FAR superior to e85 in my opinion.

ProEFI

I wish we have E85 instead of using C16 and changing the O2 sensor every 2 weeks!

Unreal

Then run MS109, or take the o2 sensors out and run open loop when using leaded gas.

JohnnyLS7

These are all GREAT points... This is a tough decision.... is there a way to monitor the meth to make sure the pump doesn't fail.... like a gauge or something... if i can see the pressure when stomping on it at high boost then ill know to get off cuz of pump failure... i have been using meth for 4 years in this setup but i'm still freaked out from all the horror stories.... thank you all for the knowledge... greatly APPRECIATED!!!

Corvettinator

Well, I have a meth pressure sensor that I can display on my HUD and get audible alerts using the Dashlogic, plus the meth kits come with pressure indicator LEDs, but at the milliseconds we are talking at 6000 RPM, I doubt you'd be fast enough with your foot.

As we discuss in this thread, tunes can be IAT (or pressure) sensitive to pull timing.

Streetk14

I tuned my last build (T-trim @ 12 psi w/ meth) to basically pull all the timing out when the IATs got above 90 or so. With my IAT sensor mounted in my intake manifold, the IATs would almost always read in the 50's-60's with meth spraying. So if I was requesting 15 degrees of timing under normal circumstances, I'd have the IAT/spark table pull 15 degrees when temps got above that.

It isn't totally fool proof, but that's how ECS tunes all their meth cars. Once in a while I'd get a little bog when going WOT if the engine was really heat-soaked, but it was either that or raise the temp threshold where the timing is pulled. I felt better with it as I had it, but basically the idea is this: Meth fails = PCM pulls massive timing and engine falls on it's face. You notice this and get out of it.

If you read that link I pasted to the flex-fuel module meth setup, he was actually using the flex-fuel module to allow the PCM to lean out the mixture (if desired) and add timing when meth flow is detected. So he basically has two tunes. The more aggressive one is triggered by the meth pump activation.

If you were running E85, these PCM tables would be there to alter the tune based on alcohol content in the fuel. When using it with meth, it would just be an on/off thing, but seems a lot better to me than the IAT sensor method.

JohnnyLS7

Great! THANK YOU!

JohnnyLS7

Great! THANK YOU!

Milan

What is your opinion based on? GTR guys are making way more power on E85 than race gas.

E85 is better in every way, cheaper, more knock suppression, cooler combustion temps....what's better about race gas? Only argument is race gas is more "consistent" because it doesn't fluctuate like E85 does some places.

You haven't seen it in the LS world because we are way behind the times when it comes to technology for making power.

Blackonblacksls

My turbo car would even spool quicker and make more torque on e85 than c16

n_brio

here is my e85 build
http://forums.corvetteforum.com/c6-f...5-results.html

JohnnyLS7

NICE!!!

Cold6.2

In for info also, Johnny maybe someone will post actual parts needed or a kit and wont keep telling you to run something else.