subbing to come back to when I'm ready. wow 53 pages...

Odd. Yeah, I think I would take the spill valve completely apart and see what's going on with it. I'm back on 93 and haven't had a single issue (it's kinda nice, haha).

Phate running 93 is like Jimmy Hendrix without his acid.

Yeah, he could probably play better than most, but the magic is gone.

But Jimmy is dead while Phate continues to mash on dose buttcheeks!

wow. finally finished reading through this thread 54 pages of greatness. i feel like i learned quite a bit about tuning this car from all the accumulated knowledge here. although im sure ill still have plenty of stupid questions to ask you guys. so be ready.

so i added timing to my 3.5gal e85 mix tune, i havent really got alot of miles logged on this new revision. coming home tonight i figured i grab a 3rd gear log real fast. its a pretty wide turn to merge on the freeway once it straightened i gave it the go ahead felt some good spining initially!:bigeyes: on my new gforce kdwv2s. how does this log look? all criticism and helped welcomed it looks like my fuel ratio is good but kinda wonky i know im targeting 11.7 and 18psi tapering down.

ps im loving e85 more and more.

Looks good, although you are probably going to be able to add some timing up top (later in the rpm band).

Starting to get a little rich @ the end, but welcome to the world of continuous tweaking.

Looks ok. Scale down the maf in the end range to bring you closer to target. You barely have any top end timing...you have lots of power waiting for you :)

1.00 2.44 6.50 8.00 9.50 11.50 13.00 14.50 17.00
heres my timing @ 2500-6500rpm for my next tune revision

What was your previous timing?

I've seen good 93 octane run that much up top ;)

That's a solid curve so far.

not to sure maybe minus 1-2* near the middle on up.

You can go leaner than 11.7. I was running 12.2 on straight 93 pump has.


Tapadatass

yeah been thinkin bout goin 12.0 once i get things nice and smooth.

Ok, so I'm talking to a chemist about cars right now and particularly the effect of water condensation from ethanol weakening the internals of our engines. I was just curious if this was a major concern for us and if it has the possibility of shortening the lives of our engines?

What specifically is he stating about "water condensation from ethanol"?

Is he talking about it carrying moisture into the cylinder in liquid form since it is hygroscopic or the fact that the combustion products are heavily water laden?

Neither is an issue IMHO.

To keep it simple, why is it your opinion that it is not an issue? To be clear, I'm trying to learn and understand here.

WMI

Got to believe more H2O delivered via this method but I'm not a chemist. Lol.


Tappin

Damn, I need a chemist cuz I'm talking to a chemist! I am just curious how we don't have to worry about engine internals deteriorating due to ethanol?

I am curious about meth too though, because as far as I know (besides hydrolocking) meth/water mixing doesn't result in many blown motors at all?

And are flex fuel engines any different, or is it just the pumps and lines?

Water condensation in a HOT ASS engine in an even HOTTER combustion chamber. Next.


Edit: WTF does this guy mean by "internals"? When we say internals, it means crank/rods/pistons and shit. I hope he means something else, lol.


Edit 2: When it comes down to it, we have no idea what long term affects E85 will have on our cars.

We do know the short term effects of E85 on our cars though....POWER!!!

I can only ASSuME that he thinks it is a risk that the alky/water will result in oxidation of the exposed metal in the combustion chamber leading to thinning/weakening over time. I would point out the millions of vehicle-years of operation with people running either E85 or water/meth injection as anecdotal evidence that this is a non-factor.

There certainly isn't any condensation going on at those temps in the combustion chamber as Phate mentioned.

Also, the normal combustion products of gas and oxygen are CO2 and water, so it isn't like there is now way more water in the combustion products than before (a little more due to the alky having relatively higher H/C ratio than gas, but nothing important).

On point 2 you are correct Sir! But that is what they make full rebuilds for, I know that beating the crap out of my car on the track and autocross is not giving any extra life to the motor either, but I'm having fun! E85 just adds moar fun till zoomzoomboom.

Just the rubber compounds, higher flow injectors/pump, and the tune.

All the smart in this thread is giving me a stiffy.


Tapadatass

Tell your chemist friend to head back in the lab. The engine probably ingests 10x as much water on a rainy day just through humidity in the air as what ethanol will carry with it.

The only possible in cylinder effect I can think of is the higher fuel requirement resulting in more cylinder wash down leading to loss of compression faster. And I would consider that a very low risk.

My concern over E85 has nothing to do with the fuel. It allows more timing and boost, allowing gobs more torque, increasing the stress on the rods, possibly past their fatigue limit.


Zigatapatalka

Flex fuel vehicles also usually have an ethanol content analyzer built in and can adjust the tune if necessary.

Good thing to have given the variability of ethanol content from pump to pump and the winter vs. summer blends.

Ok, so this came up in a drunken (buzzed is more accurate) debate last night when we were discussing my blown motor. I'll post up more later, but the current thought is that I was probably past mbt in the 4000-6000 range.

He mentioned that the engine was probably weakened (I used the word internals cuz Idk what else could be weakened) by water oxidizing the metals like 12 pack mentioned.

So, flex fuel engines don't have anything special done to them to help them withstand the effects of eth, right? The difference is in the fueling system, correct?

Thanks, replied while I was posting

I think that rain comment should be a critical piece of info.

You are getting beyond my materials knowledge now, aluminum has a very tough oxidation layer on it that forms nearly instantly when exposed to air, water or no water. It's what makes it so resistant to corrosion and why you have to use a tig welder on it. I can't think of what e85 would be able to do to breach that layer that normal gasoline combustion would not do.

It sounds like you are thinking it would somehow make the materials brittle, like hydrogen embrittlement. I do not think that is possible. It's most likely the rod that failed, which isn't even directly exposed to combustion.


Zigatapatalka

does your chemist friend know that one of the resulting product of burning hydrocarbons is water? A lot of water is created.

Edit: beat to the punch by another chemical engineer. Chemical engineer >>>> chemist

Most chemists i've met are retarded.

Sometimes chemists don't know about cars, and car guys don't know much about chemistry.

We are lucky to have guys here that know about both.

Take it easy on ck. He is a good guy, and reads quite a bit on msf, as well as contributing quite a bit.

^^^^ that's why I love Msf. we have chemist/car nerds and those should trump a chemist who is not a car nerd any day.

... When I use my phone for this shit, I struggle to see all responses before replying, so to try and be clear, the fact that I was past mbt was not discussed with hemist friend, he and I were only debating the effects of ethanol (via water) oxidizing (not condensation like I wrote) the internals and weakening them and that causing my fail.

I didn't have the words, but my simple thought was that we have highly educated nerds pursueing and checking in in these treads and if this was an issue, it would surely have been brought up. I just needed everybody to give me their scientific reasons for me to respond.

... "go on with the boriphyll"

Sorry to hear about the blown motor, recent?

Yeah, happened Saturday, it's mentioned in my build thread and I'll post my timing tables later and fill in any questions people have over there.

Real, I'm not upset, just embarrassed if I made the past mbt noob mistake. But honestly, the bigger the mistake, the more you learn... Hopefully ;)

Don't forget all the random leaness u had

Older FFV systems used a sensor in the fuel line; newer systems just have an algorithm in the ECU that detects changes in stoich and fuel trims to determine if the fuel is petrol or E85.


Tapadatass

@silvapain you so smart me wuvs you

Not to stay off topic, but te leanness wasn't that bad... I don't think anyway. I think past mbt timing+thousands of miles and 100s of WOTs makes the most sense.

I never seen your timing im curious as to what you had setup...I know that my very last map on 50/50 was a mirror image of xmt66 cobb pro tune values....

Ck, who suggested you were past mbt?

Also, how much e85 and meth were you running?