E-10 isnt great gas to race with. Even at 93 octane. It does the job but for how long? In some states im sure E-15 is the minimum many have at their disposal. Seriously and I thought E-10 was bad.

Well given today’s economy and the control of flexible commodities our Bankers have acquired (Ethanal Credits). Im sad to say E-15 isnt far from taking over….maybe even E20 soon???. Blending ethanol in our good ol 93 ocatane fossil fuel is a nightmare for us who drive old cars. Or is it? I am a beginner in the tuning subject, but how does that do for a modified Z24 against a stock bone RS cavalier?

Given the fact that running E85 or even E47 is a touchy subject on this forum. Is it something we should be concerned with? Given an article ive read Bankers have own oil tankers and sell ethanol credits like it was a commodity simply to meet federal requirements of blending ethanol. This in turn will drive gas prices up. Which as well cause them to mix more ethanol in the gasoline. I cant even use E-15 in my lawn mover or weed eater. Fuel stabilizer anyone?

Im in the process of selling my 2010 SS/TC which runs E85 fine. Heck at $2.60 a gallon of that corn I don’t complain. MPG’s is another topic.

To get back on topic, once my Cobalt sells I plan to finish up the Z24. However I would like to prepare it for an increase in ethanol blend in the mix. So now this leads me to this question. What needs to be done to a Z24 to run “FULL” E85? Or at the minimum E47.

Injector orings, fuel pump? What else? Do fuel lines need to be changed out?


GMR has got nothing on this

I run mine on e85.

stock fuel lines. Aftermarket pump and injectors only (though these were initially increased for a turbo application anyway).

If I had a stock cavalier to play with I would think that larger injectors and a wideband and a tune are all that are really needed. I had mine set up for a tune on 60's and 93octane. I drained the tank and put in e85 with a larger pump and 80's... part throttle afr's were right at/around 14.7 before tuning (on an innovate gauge that wasnt recalibrated for e85). There are probably a few tables that would make it ideal but I havent found a problem with me setup and I beat the bejesus out of the car on 20psi lol.

The only problem (thats not really a huge issue) is warm start/cranking. If I dont give it some throttle it wont fire, but once it catches its just fine. Cold start or after its cooled down past a certain point it starts just fine on its own. That one we have not been able to figure out (its probably a hidden ECT reference for fueling table of some kind I venture to guess).

Fuel filter is a must. e85 cleans the hell out of the tank. Mines a different color in there now after about 4000 miles.

This is on an 02 PCM. I dont know about older model PCM's if they would act the same. its a p11 on an LN2.






"A car just isn't a car without a little blood, sweat, and beers." -- Shadowfire

damnit Raf...is that Z24 ever gonna see the road again? The last time I remember seeing that car run was when you raced me with your turbo and my cav was bone stock lol.
I still dont understand the desire for E85 on a dd..I want to enjoy driving my vehicle and filling up anywhere anytime with 93...Id hate to have to plan my cruises and trips (especially on the back roads) around being able to make a round trip. There are no E85 stations where we cruise in the back country...you'd be SOL.

but its a damn sweet Z..cant wait to see it up and running again. Though good luck with the bs you'll hear from you know who for selling the TC and investing more into the Jbody..if you run a jbody these day's youre pond scum to anyone thats moved on with a certain said group lol


04 Cav. 2dr. 5spd. My DD. 'Nuff said.

^^ Agreed on availability. I did it for the octane really. I only have 2 stations locally that have it. Its not horrible cause I have 2 other vehicles I can drive. I can go like 250 miles before I need to refuel the car (I dont let it go below half tank cause of the pump setup I dont want to fuel cut).




"A car just isn't a car without a little blood, sweat, and beers." -- Shadowfire

disclaimer: i have not yet tried E85 in a j-body. so take what i say here for what it is, merely gathered information and hypothesis. but again, not real world tested results. i have read a lot about e85, talked with a lot of people on the subject as well as argued for days about it lol.

with that said...
raf they dont mix the ethanol in with "93" octane. they mix that ten percent in with most likely 91 and then the octane jumps up from there due to the ethanol content. straight e85 is around 105 octane.

basically what you need to do is make the fuel system 30% larger, or abouts. all you'll really need to acomplish this is the equivilant larger injectors. if that puts the fuel pump past where its comfortable, run a meth kit to even out the fuel needs. not only will you get the added benefits of cooler iat's you will be able to add meth per boost, not just turn on a garden hose and hope for the best with upped fuel pressure. in the end fine tuning is going to be key with the PCM via HPT, though.

the reason why we can run E85 in our cars is because we have what is called an oxygen content sensor (or o2 sensor) that senses the oxygen content of the exhaust stream. this data that is calculated by the sensor is called "lambda". in "lambda" E85 stoich is the same as it is for straight gasoline. yes e85 requires more fuel to be stoich but it does not matter in this case because our sensor does not read fuel content, it reads oxygen content. the PCM is going to see these calculations as air fuel ratio but its because the originating data was calculated from "lambda" that it does not matter. the pcm sees what the o2 sensor sees, and that IS "lambda". i dont care if hp tuners tables say its air fuel ratio, it is not air fuel ratio, it is based off of oxygen content ONLY. and for those that say wait a minute, thats not right... go ahead and answer me this.... "how can a narrowband sensor read actual air fuel ratio?". simple answer, it cannot. it can only read in terms of RICH, LEAN, OR STOICH. we do not have a wideband sensor, we have a narrowband sensor that again, reads only oxygen content.

everything i have just talked about has to do with low speed and drivability stuff. WOT is completely different, the pcm goes into set tables for wide open throttle. these tables will need adjusted to what a wideband says anyways. so again, fine tuning will be needed.

so yes, run e85. the only issue i see is the ethanol content changing... and if you have a meth kit, the octane loss (which is negligable) will be made up for. as for it running rich due to having more gasoline content, well, its not enough to worry about, or so i have read.





RIP silver car. You will be missed.

Ill find out what happens this winter when they change the content of the e85 in my area. I have a tester to see what the content is and how the car reacts to it. Honestly it'll probably be a negligible difference and I bet the PCM will compensate and I wont even be able to tell the difference except at WOT (Im hoping with cooler air and a richer fuel mixture that the car might make a little more boost and compensate up top anyhow).

Its pointless to be wot on cool pavement anyhow :p

As far as fine tuning with HPT, we disconnected the o2 sensor and tuned the pcm to be as close to 14.7 while doing low speed driving (drive it how you drive normally and adjust the tables). Then hooked the o2 sensor back up and it ran like stock. It was very close before fine tuning it but after the only difference was the car smells like moonshine rolling down the road .

There is way too much nonsense about e85 out there. I brought my car into my buddys mechanic shop and he thought I was nuts, told me that the fuel burns too hot. 2 or 3 other people are shocked that the fuel tank and lines havent melted yet. A few others cant believe that they just got stomped by an 8v motor running e85 in their v8 "fast car". NOT ONE person believes the car isnt running an aftermarket system for fueling.

It really blows my mind how narrow-minded people decide to be with this fuel; thats ok though, I like paying nearly half the price of 93 . Just the other day I was filling up and a mustang full of ignorant hicks rolled up shouting about how it wasnt a flex fuel car and that Im a tree hugger... Lets just say I didnt even need traction to pass that POS.

All this said, if my car explodes due to an issue directly related to e85 I will be the FIRST person to come here and let everyone know what the issue was; I really cant see how thats gonna happen after what the car has already been through.





"A car just isn't a car without a little blood, sweat, and beers." -- Shadowfire

Derek I just sold the SS two days ago. So now that allows a bit of room for spending on the Cavalier. First step though is getting a front fence installed at my house. Then extending the driveway to allow more than 2 cars to park. Then a car port so i can find a nice place for the Cavalier to begin finishing her up. Oh and she goes in for paint before I bring her home.

Running the SS on a E47 blend Im aware of the issues finding a gas station that offers E85.

Brad you should try it. First hand experience is the best to learn. But yes tuning would be the final key to optimize the decision. And I wonder what injectors would be sufficient for the LD9. I plan to also install a upgraded fuel pump.

Mike, so your runnig straight E85? How is your tuning going? 8V? So is that the LN2?


GMR has got nothing on this

Straight e85 on an ln2, yep!

The tuning actually was the same for e85 as it was for 93 really only the car runs more timing and we did the extra step of tuning the tables with the o2 sensor disconnected to get a solid baseline so the PCM didn't have to work as hard with the o2 connected.

I think theoretically if it's a stock motor just getting injectors that are 30% larger should get you close on a stock tune without changing anything. I would love to try that. If it's a performance build I would just get the biggest ones you can afford for it so you have headroom.

I'm by no means an expert on the subject but mines been running great for a lot of well earned miles lol. Again I say that if I pop the motor I'll let everyone know if it was e85 related but I don't think it will be.




"A car just isn't a car without a little blood, sweat, and beers." -- Shadowfire