E85vs98 N/A? realistic?

[Nuddy]

E85 is not magic. Especially in an NA car. You've obviously done something not quite right.

True all E85 means is it is 'up to 85% ethanol' It does not tell you the octane rating, which is the thing that matters.
98 is 98 octane.
Regular pump E85 is 105 octane.
'Race' pump E85 is 107 octane.
The V8 supercar E85 is more (secret).
If you could get hold of 107 octane non-ethanol fuel it would give the same result as 107 octane E85 but use much less fuel.
EFI engines will self compensate (as long as the injectors have sufficient max flow rate) but engines with carby's will run very lean and will need re-jetting.
Any engine going from 98 to 107 octane with no changes will actually produce very slightly less power.
A NA engine going from 98 to 107 octane with the appropriate fuel and ignition settings and increased compression might get up to 10% improvement.
A turbocharged or supercharged engine going from 98 to 107 octane with the appropriate fuel and ignition settings and increased boost might get up to 30% improvement. This based on the engine being initially well tuned for the 98 octane fuel.

[NitroDann]

There is a bit more to it than just how it performs during RON testing.

Dann

[ManiacLachy]

...
But 22l/100km is just a bit much.

22l/100km on 98?

What were you getting on the corn?

[StanTheMan]

I figure my 98 fuel table isn't as aggressive as my E85 like madjack suggested earlier. It can probably do with some more tuning. 90% of my tuning has been on E85.
They are totally separate tunes.

[StanTheMan]

...
But 22l/100km is just a bit much.

22l/100km on 98?

What were you getting on the corn?

Ive got the corn down to 17 lt. part of that could be that its more like 65-70% for winter months.

alo I haven't sat there for an hr playing with idle for a while

[Magpie]

The Australian Standard for E85 is between E70 and E85, if you are getting below E70 then the servo selling it is in breach!

To date, even during winter mine has not dropped below E79!

In a nutshell E85 is less energy dense than 98 so you WILL use more for the same amount of power there is no getting away from this fact! When E85 is used the chances of detonation is reduced (because there is more fuel being injected), hence you can add more timing. All you need to do is look at the EGT's to see the difference between E85 and 98, E85 runs 'cooler' than 98. I'll go through some old data logs and see if I can post some EGT's with the different fuels.

Gasoline (petrol) 46.4 MJ/kg
Gasohol E85 33.1 MJ/kg
Lignite/brown coal 10 MJ/kg
Natural uranium, in FNR 28,000 GJ/kg

[StanTheMan]

E85 I run at 88 deg cel. 98 I run at 92.deg cel i'm using the RX7 type temp sensor in Tuner studios

as far as the fuel consumption goes. Its actually right on target.

current engine set up on 98 gets me around 350 km on E85 I get around 220. at around 38 litres. actually when you do the numbers. is actually right on.(thats if I'm doing my numbers right )

standard engine used to get me around 400 km....

[Magpie]

Fuel temperature is another issue!

[StanTheMan]

ohhh right. The Flex fuel sensor will give you that.....right?

[Magpie]

Depends, the Haltech PS1000 cannot get the fuel temp from the flex sensor, however the Elite can.

With respect to temperature:
98 has a lower flash point than E85. 98 is more volatile not surprising as it is more energy dense than E85
E85 boils at a higher temperature than 98

Ethanol boils at about 78°C
Uranium has a melting point of 4131°C

Trivia
E85 affects the formation of some firefighting foams as the ethanol dissolves in water hence the foam will deteriorate more rapidly than if used on 98 fire. Yes this is trivia as we use powder type fire extinguishers in our cars, but it does also explain the hydroscopic nature of E85.

[StanTheMan]

Depends, the Haltech PS1000 cannot get the fuel temp from the flex sensor, however the Elite can.

With respect to temperature:
98 has a lower flash point than E85. 98 is more volatile not surprising as it is more energy dense than E85
E85 boils at a higher temperature than 98

Ethanol boils at about 78°C
Uranium has a melting point of 4131°C

Trivia
E85 affects the formation of some firefighting foams as the ethanol dissolves in water hence the foam will deteriorate more rapidly than if used on 98 fire. Yes this is trivia as we use powder type fire extinguishers in our cars, but it does also explain the hydroscopic nature of E85.

Just checked. MS2 pnp has nothing in the flex fuel about temperature. Unsure about the MS3.

but since we are talking trivial stuff.
E85 runs a little colder
Hotter spark would give it more chance at cold starting.

If you say you went 1 step hotter than the recommended. that should theoretically not make a huge difference on the running of the engine but give you better starting? Or maybe even 2 ....on an N/A engine. On turbo its probably not a good idea since it probably runs real hot once you start giving it some stick....
Or is that difference trivial?

[Magpie]

The plug needs to be matched to the operating temperature of the engine. Not to mention the plug needs to get up to the correct thermal temp to self clean.

Starting is no done very often, mine is a pain to cold start when the air temp is below 10

[Magpie]

on 98 going down the main straight of QR on 01/05/2014 (Innovate Data)
98 EGT by Eipeip, on Flickr

May 2017 on E85 down the main straight, about 10kmh faster now and EGT's about 70°c cooler. Plus the gear changes/lift offs are more obvious (drops in temp). Data from Racepak. Note the same EGT sensors were used.
E85 EGT by Eipeip, on Flickr

[StanTheMan]

I'm talking water temp. Youre talking actual temp inside the cylinder.and have the means to measure it as well...