I am switching to E85 because it has the potential to allow the engine to be built for more power and it is cost effective in my area. In WI E85 is $2.00 per gallon and 93 octane is $3.05 per gallon. With E85 my truck only gets 30% less fuel economy but the fuel is 50% cheaper. The main reason I am switching is that the higher octane rating of E85 allows you to run more compression for an additional power gain that you cannot get with gasoline. The 429 CI SBC that I am building will be 12 to 1 compression and in a pinch can run gasoline but will be setup for E85. On my all stock 5.3 litter truck the E85 fuel made 11 more RWHP then gasoline. On my 555 BBC drag car with E85 the car made 73 more RWHP when I switched to E85 over race gasoline. All these cars are N/A in blown applications the power gain potential is even better.

 

I have no respect for Goss. I saw a video where a tech school took a gas Chevy pick up, and with only a tune ran it 100,000 miles and took the motor apart. It was all in good shape. I only have a few thousand miles on mine but so far so good.

 

Like stated, the common misunderstanding has been the methanol vs ethanol issue. Methanol is clearly corrosive and that's well documented. I think the ethanol incompatibility issue has been pushed by the auto makers. They don't want people pumping e85 into their run of the mill vehicles leading to lean conditions and engine damage that will need to be covered under warranty.

There's a LOT of misunderstanding when it comes to fuel. The proof is with the people who have the Cavalier that "only run the good stuff" and pump it full of 93. People think 93 is better than 87, and all they know about E85 is its cheaper.

The only vehicles I think could possibly have E85 issues are vehicles from the mid 70's or older. Ethanol has been added to gasoline since the late 70's, so rubber seals, lines and everything else have been formulated on vehicles built since to tolerate the presence of ethanol.

 

how hard is it to tune for e85?

 

E85 tunes pretty straightforward. Some people get caught up in the stoich ratio of ethanol vs gasoline and wonder what you use for a wideband. The reason being people see widebands read 10:1-20:1 ('ish) and they see stoich of E85 being in the 9's. These figures are just calculated based on deviation from lambda. O2 sensors are lambda sensors, not sensors specific to any type of fuel. They can calculate ideal burn of anything, and show deviation from that point. So, with that some widebands can recalculate on their own and read an E85 a/f numerical value. For some model of widebands that tune, you can just tune vs lambda.

As far as tuning goes, E85 tuned very much like gasoline, but tolerated more timing much like race gas. The only issue I felt was noticeably different, was E85 wouldn't tolerate light load/lean conditions like gasoline. In some of the lighter load cells, where you'd typically see ratios leaner than stoich, E85 struggled at times and misfires became apparent. I just couldn't get E85 to be stable at lean ratios under certain loads that gasoline would. I explored these areas quite a bit, because while my wide open throttle tune had been long done, I was searching for more gas mileage.

In the end though, if you can tune gasoline, you can pretty much jump right in and tune E85.

 

See my original post. Really, all I did was scale the base fuel table and it ran great. Seems like I made my base tune richer than most people (140%), but that's what the numbers came out to when I did the crunching, and the WBO2 shows lambda 1.0 so it looks correct. You may have an injector constant that will do the same thing but that didn't exist in '85.

Granted I only have a handful of miles on it but so far so good.

You can also fiddle other things like timing to try to make some gains but it will run nice without any of that.

Keep in mind that maximum advance before knock does not necessarily mean maximum power.

 

I dunno. I changed my valve stem seals a number of years back and it really isn't that hard.

Come to think of it, I doubt fuel would even reach those seals so I really can't think of any seals that could go wrong.

 

I had to do some tweaks for cold weather that you would not need in Las Vegas but other than that its pretty simple. Just need more fuel. Now I'm trying to fine tune for performance and thats hard to do on the street.

 

You tuned the car for 1.0 under wide open throttle? "Fiddling" with other things certainly has an impact. Merely doing an air/fuel tune isn't going to explore any of the potential of the E85. That's basically just running it to say you do.

Noone with knowledge of fuel injection tuning goes for maximum advance, you push for MBT which provides minimum timing for maximum torque. Advanced timing is negative work, therefore the least amount you can run for maximum effective pressure at optimum crank angles is all that is necessary.

 

^^^you lost me lol

i really wanna run e85 with my turbo....

maybe i should have it professionally tuned or i can track tune to see my results

 

No, my tuning for stoichiometric was for part throttle. I enriched WOT even further so it ends up being about 0.8 lambda. I also have timing advanced a bit too but my point was simply that getting the car to run about as well on E85 as it does on gas is pretty straightforward. That is is just a starting point. I expect the reason most people want to run E85 here is because of a power adder and that requires all sorts of changes. I am using a separate bank for nitrous as an example.

Agreed, but you would be surprised how many people tune the advance so they are just on the edge of knock. My point was while that may work for some fuels it will not get MBT for E85.

Since there are probably a few people who are new to tuning, specifically for ethanol, here are some things I have learned that are probably of use to others. I am certainly no expert though so anyone else who has experience please post your tips also.

1. E85 has less energy density than gasoline so you need to burn more of it. Stoichiometric AFR for E100 is 9.01 vs. 14.64 for gasoline, but density is higher for ethanol at approx. 0.789 g/ml for vs. approx. 0.73 g/ml for gasoline. Work it all out and for end theoretically you need 140% more volume for 79% ethanol content "E85" than for gas.

2. E85 has a wide MBT (maximum brake/best torque) range. You can achieve, within 1%, maximum torque from about 0.71 to 0.88 lambda.

3. E85 has a AKI of about 105, which means you can do things with E85 that you wouldn't think of doing with pump gas

There is a lot of info out there. You can start by reading a page such as http://www.eco-flex.us/pages/E85_facts.htm or one of many wikipedia pages like http://en.wikipedia.org/wiki/E85_in_standard_engines to get some background.

 

jsiddal, I'm talking about head damage - inner-pocket pre-mature wear &/or the valves from the E85, not the seals. I've got RR & aftermarket springs I did myself, so I understand no damage could occur there. The article mentions difference in metal composition within the head. Now if bjankuski is having success with his builds and no head damage, that is some positive confirmation....

 

I think they are just talking about valve coatings and seat material not the rest of the head. I expect these are changes to allow very long life of these components since all real-world results I have seen so far have not shown any corrosion/wear. Ethanol is mildly corrosive to some materials though so there is the possibility of long term damage.

If you are interested in doing the work you can learn this stuff. Nothing is really that difficult. Learn the basics and after that it is a lot of trial and error.

Paying someone else to do it does not necessarily get you the best tune.

 

What was MPG before and after? what was cost to date? How much is E85 per gallon? If the gov. stops helping with price it may go way up. I like the idia Good luck