slash128

That really would be sweet but I get the sense that it is not linear. The source of my suspicion is that the anti-knock index difference between E50 and E85 is only a 0.2% increase (95.6 for E50 vs 95.8 for E85). I just haven't found anything that examines blends between E10 and E50 to know the properties there... But it must be a pretty good ramp since they show a delta improvement of 4% from 86.8 RG to E10 and over 5% improvement from E10 to E50...

Also, I was getting timing pulled on E10 92 at low 10 AFR, yet seeing absolutely no timing pulled on E50 at 11.5 AFR...

But I would suspect that E10 92 is likely better than e-free 92... And if you have a way to use it then go for it! I think the only downside is fuel economy, but we're not in the boost game for max MPG

9krpmrx8

iTrader: (46)

Oh yeah the fuel economy sucks, But if you have a turbo 8 and don't have a daily then you are braver than me.

slash128

Amen brotha!

Brettus

iTrader: (2)

The ideal for me would be ...being able to run 10%ethanol without having to change the tune and then eliminating WI . I would need to be able to drive anywhere in the country so being able to bung some ethanol in for track days and max power around town could be sweet .
Just went down and grabbed some ..... got a feeling this is going to get crazy !

The way I see it .... you can't add 10%ethanol into 92 without it improving the octane rating .... by how much

slash128

LOL looking forward to some craziness!!! Just don't blow it up

logalinipoo

I'm not positive but pretty sure. Most us gas is crap, but they add up to 10% ethanol to bring up the octane to the rated number. So sometimes you see stickers that say may contain up to 10%ethanol. Sometimes they just say 10%ethanol. If it's being sold as 92 with a 10%ethanol sticker than its just that. It's a big deal in some places to get pure ethanol free gas. There they'll have the efree.

If it's being rated as e10, e30, e50, e85 on the pump label than it's actually mixed.

I know for sure most stations carry low level gas and high level gas. Then mid grade is a 50/50 mix at the pump. So I wouldn't be suprised if ethanol mixes are the same.

madrotor

Great stuff going around about the fuel mix , I was wondering has anyone tried mixing Xylene with your normal petrol

Xylene has 117 octane rating and this could yield a massive increase in your overall octane rating without actually increasing your fuel consumption much considering that the energy content of xylene is actually higher than gasoline.

The basic formula would be
((Xylene's octane rating ) X ( Volume of Xylene) + (Fuel's octane rating ) X ( fuel volume) )/ Total volume

for example
take 5 gallons of xylene , 12 gallons of petrol
(117)X(5) + (93)X(12) = 1701 / 17 = 100 octane rating
add your 2T premix to that for lubrication at 2-5% of total volume ( Xylene is pretty dry ) you get racing fuel and obviously the more xylene you add the more octane you get but again the stuff is pretty dry and will through rubber seals so with 30% you get more than enough octane to completely mitigate knock.

hoss -05

iTrader: (4)

Ugh, I wish Denny/Oldragger was still around to see some of this. He was really getting into fuel tuning at the end of his run. I miss that guy.

slash128

I've briefly looked into additives such as xylene, but information seemed to be scattered. There were drawbacks that I wasn't prepared to deal with such as carrying a can in the trunk of my DD and mixing at the pump But if it has benefit then I am open for discussion on the subject if you have experience to share. Have you used xylene?

slash128

Wait, no disrespect, but did he pass away?

hoss -05

iTrader: (4)

Neah. he moved on and had some life changes.

slash128

Oh phew, heh, the way I read that sounded rather ominous... I only know him by his posts that I've read here, but in that regard I count him as one of the good ones. So... glad to hear he "moved on" vs "passed on"!

slash128

So of course I see xylene and immediately start googling to see where I left off. Well this comes up... The topic started by the OP is funny enough but the GIF in this guys sig is what got me sidetracked

My home made Xylene race gas experiment goes horribly wrong. Where did i **** up?

Watch the blonde and wait for it...

Brettus

iTrader: (2)

That's nasty !

slash128

madrotor

Hello guys, sorry for the late reply, I am on the other side of the pond. I remember reading that post on the supra forums , real nasty stuff. I also remember finishing it, and it turned out that he had other issues and Xylene just came in the way ( If my memory serves me right ) please correct me.

Whilst I don't have any personal FI experience yet, all I know was that some one my scooby mates used it when they wanted to push higher boost and E85 isn't easily accessible here in UK , in addition to that , Back in the day they used to use toluene/Xylene in formula 1 as fuel and we all know what kind of boost they ran into these engines dont we

slash128

So... I've been playing with the APV open RPM and have come back across a phantom issue that seems to have persisted with the car for years...

Way back prior to turbo I was having an issue that if I drove the car slowly to redline in 1st or 2nd gear there would be a hiccup and the car would buck. Back then I knew even less than I do now and didn't dig in to logs, but at the time I did find a MAF screen in my MS CAI that had turned sideways. After fixing it the problem seemded to go away and I never looked back. But I really don't drive the car slowly to redline in low gears (or any gears for that matter) as a regular practice, so maybe it wasn't really gone completely.

Recently I moved the APV open RPM to 6000 to deal with a lean spot. I did some slow logs to redline in 1st and 2nd gear to check things out and the bucking was back. Looking at the logs there is definitely a spike in MAF output and AFR. Thinking it was the APV I started throwing fuel at it, moving the opening RPM around, even keeping the APV closed until 9.5K RPM, but nothing seemed to affect it. The other odd thing is that it happens around 6K RPM in 1st and around 5500 RPM in 2nd, pretty consistently. Finally today I disconnected the APV connector entirely to make sure it was staying closed and not causing the issue. Guess what... the issue persisted. I don't have any MAF screens anymore, just the honeycomb, which I checked and it is not loose or otherwise goofed up.

I'm a bit baffled. Does anyone else experience this? Attached is a CSV with some samples from 1st and 2nd gear. Are there any other valves that open in this range? My VDI was kept closed by setting to 10K RPM. SSV was set to stock...

Brettus

iTrader: (2)

I noticed mine does the same thing the other day . Like you , I rarely accelerate slowy so haven't seen it before . I'm picking it's the changeover point for the P2s kicking in that does it. I haven't even bothered to try correcting it because ................ well you know why . lol

slash128

Ok, as long as it's "normal" I'll quit fretting

Brettus

iTrader: (2)

def. not "normal" but not much of a problem either ................... just log it and adjust in the load cell where needed.

slash128

"normal" as in I'm not the only one

The problem I was running into is that the RPM range changed. So adjusting for it in 1'st was not effective for 2'nd, etc. I think I'll just ignore it and not drive so slow

Brettus

iTrader: (2)

i found a spike at 5500 in 2nd which matches up with when the p2s come on line at light load .

slash128

Cool, I feel better now. Sometimes I get so wrapped around the axle on the littlest things

slash128

Back on the high octane fuel topic... Anyone seen this stuff? Could be snake oil

RACE GAS | Racing Fuel Concentrate

I just barely came across it a few minutes ago and planned to read more about it but figured I would share for anyone else that wants to check it out...

Personally I'm still pretty happy with the E50 blend. The price recently came down to 2.69/gal locally.

Brettus

iTrader: (2)

you are better off on the E50 I think . You don't get the better combustion cooling/cooler running with high octane additive.

I read on an old post that fuel filtering can become an issue when running ethanol .... had any issues yet slash ?