Best Fuel - recommendations

[Tien GtB25]

Guys,

Please dont hate me for asking questions about fuels - BP ultimate / E85 / Etc.... YES i have read the thread on E85 fuel and yes i am still confused - hence my questions.
Im dont want to research into fuels - where, octane rating and all that ... sorry but i got better things to do... dont get me wrong the understanding will be great but do you spend time researching about pineapple for the best topping in a hawaiian pizza?

Correct me if im wrong

1- E85 fuel will be better (power gain / fuel economy) for our Libs, provided it tuned propertly with fuel filter changed?
2- In order to run E85 your Lib will need to be tuned before filling up? ((Hooking up with Matt from KT soon ... this will be perfect)
3- How much power gain can I expect to see from this fully sik wonderful juice?

which lead me to my questions

1- Tightazz question - how much do u expect to save per year?
2- If your car is tuned for E85 / E100 - United / Liberty stations are the only place to get it right ?
3- if your up shitz creek and no United station around, will the Lib choke on say Caltex premium / BP fuel ?
4- If ur Lib did choke and you limped home on I-mode do you need to flush it out and get back on the United's juice ?
5- What if tomorrow United / Liberty stop to exist, then what .. Retune again for BP Ultimate and the rest?

IS THIS ALL WORTH IT ? seems like alot of effort to save a few buck here and there (feel free to insert $$$ saving per year arguement)..... If i was a tightazz ... i'll buy the damn electric hybrid toyota already.

It would be appreciated you guys can let me know .... in simple English.... and recommendations too by all mean.
Tien.

[HardwareBoB]

If you are going E85 for fuel consumption, you are doing it wrong. It should net you about 20% more power, but critically, a bunch more torque down low and earlier spool.

You need to upgrade the pump and injectors to run E85, as well as have an appropriate map.

If you have a laptop in the car and a 98 map, you can reflash back to the 98 map at any time, but AIUI the map will tolerate a mix down to 50 or so?

If you run it on E85, united/liberty are the only places - correct.

If they stopped existing, then simply retune.

Nobody is (really) saving money switching to E85 - hell, nobody I have seen in this forum is saving anything It's all about better handling and power and looks and features. Is it slightly cheaper to put fuel in afterwards? Maybe. If you wanted a cheap car to run you should buy a honda! no UEC/expensive oil needed, just drive it into the ground.

[Tien GtB25]

Bob,

Thank you for your inputs. Make it easier to decide going forward.

1- Im a family man now so extracting every Kw out of the car ... i'll leave it to all you fully sick rally drivers .. might consider it when I get further along the road of modding .. again.
2- Changing fuel pump / injectors - Im too tired .. just got the car service 2 weeks ago.
3- Changing ECU map back to run 98 / source help from Matt = dont like to depend / wait on others to get things done for me.

For now ... i'll leave it....just hope I dont cross path with any forum members at the traffic light in Melb with E85-tuned Liberty.

[HardwareBoB]

Bob,

Thank you for your inputs. Make it easier to decide going forward.

1- Im a family man now so extracting every Kw out of the car ... i'll leave it to all you fully sick rally drivers .. might consider it when I get further along the road of modding .. again.
2- Changing fuel pump / injectors - Im too tired .. just got the car service 2 weeks ago.
3- Changing ECU map back to run 98 / source help from Matt = dont like to depend / wait on others to get things done for me.

For now ... i'll leave it....just hope I dont cross path with any forum members at the traffic light in Melb with E85-tuned Liberty.

Haha, I'm a family man too - that's part of the main reason I bought a liberty wagon, but it doesn't mean you can't have fun! The ECU remap you don't need help with, you can just do it if you have an tactrix openport and a laptop - but if you're not going to modify it in any real way, it's not worth it - another $200 for the tactrix, possibly a wideband - another $300, etc etc. It's a rabbit hole that I'm lost down and love it, but if you can avoid it, it'll certainly be cheaper and less full of your wife saying "wtf do you need that for"

[Tien GtB25]

The endless drone of exhaust noise I can take..... wife yap yap yap about car modding ... not so bearable.
This is why im staying away from exhaust / CAI / visual upgrades.

[jp928]

While somebody said doing it for economy is wrong, they didnt explain much. Perfect combustion with petrol needs 1 part petrol, 14.7 parts of air (by weight); for Ethanol (E100) its 9 parts of air. This means you are going to use MORE fuel for a given power output. If we guess at a ratio of 10:1 for E85, thats 9% fuel; for petrol its 6.3% - so E85 will use 42% more fuel. Unless E85 is a LOT cheaper than petrol, you will be losing big time, and if you car's fuel system is not built for E85, it can be badly damaged by E85.
jp 08 gtb 6mt wagon

[HardwareBoB]

While somebody said doing it for economy is wrong, they didnt explain much. Perfect combustion with petrol needs 1 part petrol, 14.7 parts of air (by weight); for Ethanol (E100) its 9 parts of air. This means you are going to use MORE fuel for a given power output. If we guess at a ratio of 10:1 for E85, thats 9% fuel; for petrol its 6.3% - so E85 will use 42% more fuel. Unless E85 is a LOT cheaper than petrol, you will be losing big time, and if you car's fuel system is not built for E85, it can be badly damaged by E85.
jp 08 gtb 6mt wagon

Except that E85 is not the same energy density as petrol, so although the amount you're using here is correct, you will infact get more power out of that amount.
http://en.wikipedia.org/wiki/Gasoline_gallon_equivalent
E100 has 66.67% the power of petrol by volume.
we are talking about E85 so,

Code: Select all

85*.67=56.95

which means 15% is 15% because that's petrol.

Code: Select all

56.95+15=71.95

so E85 is 71.95% as energy dense as petrol.

Code: Select all

1/.7195=1.3898

We have 38.9% - not that far off your 42%, but not the same.
The other consideration is that because you are using more fuel, there's more mass, and more torque, and more turbo spool. This means that you don't need to work the engine as hard to do the same amount of work (because torque = work). However, most people on this forum like to boosty boosty, and having more power and torque just makes you drive faster!
Based on a 15% torque increase and a driver that uses it conservatively, you can lose 15% off your 38.9% for a total of 23.9% increase in fuel usage.

So your apples-to-apples comparison figure is that E85 needs to be more than 23.9% cheaper than petrol (which IIRC, it isn't), plus you need to pay back the up to $2k you spent converting it in the first place.

So the simple answer is that there isn't a simple answer except as I said about "going E85 for economy is doing it wrong"

[Tien GtB25]

Fair points gents.

Im still not convince to proceed with conversion requiring set up / tune / fuel type availability. Until E85 / E100 is offered at every stations to ease my worry of running out of fuel, I'll stick to BP Ultimate for now.
There are higher risk in comparison to beneficial gains....but each to their own. Good luck to all. I want to enjoy the car .. fuel up and go... got enough stress in life & moddings AND hiding it from the wife for fark sake.

Keep the comments coming boys - knowledge is power !

[Manaz]

Fair points gents.

Im still not convince to proceed with conversion requiring set up / tune / fuel type availability. Until E85 / E100 is offered at every stations to ease my worry of running out of fuel, I'll stick to BP Ultimate for now.
There are higher risk in comparison to beneficial gains....but each to their own. Good luck to all. I want to enjoy the car .. fuel up and go... got enough stress in life & moddings AND hiding it from the wife for fark sake.

Keep the comments coming boys - knowledge is power !

It isn't all that bad.

A new fuel pump is only a few hundred dollars (and it's a totally invisible upgrade, I did it for my car which still runs only P98). You can consider this a safety-net upgrade (and you have to do it at 100,000km anyway I believe according to the log book servicing guides).

ID1000 or similar injectors can be had second hand from a few hundred dollars upwards. They're a more involved upgrade (I did my own fuel pump, I wouldn't do my own injectors), and there are some "side effects" - the fuel usage reporting on the dash/satnav will be wrong, and you need to tune the car for them (along with the E85).

Your exhaust gases are cleaner on E85, you'll get more power (and you'll get better drive-ability in the lower-rev range, as the turbo will spool sooner) with lower risk (E85 has a higher octane rating, and is less likely to pre-detonate). Yes, it does have a lower specific power than petrol, so you will chew a little more of it - but E85 is quite a bit cheaper than P98, so the $ per km costing is pretty close.

E85 (or e-flex) is pretty common these days. And even if you can't get it, the process to flash back to a P98 tune is literally about 5 minutes long.

I've chosen not to spend the money on ID1000s at this stage - but it's the only thing holding me back on an E85 tune.

[Tien GtB25]

Manaz,

Just this right ?

1- E85 = need to change fuel pump(type / cost / brand / recommendations ?) & require retune. (understood)
2- Id1000 injector upgrade = why ? (is this a requirement for E85?) / require retune ?
3- If flash back to run 98, injectors needed to be changed back ? / require retune ?

Sorry to be a pain - need to know / convinced.
Thanks - Tien

[Manaz]

Manaz,

Just this right ?

1- E85 = need to change fuel pump(type / cost / brand / recommendations ?) & require retune. (understood)
2- Id1000 injector upgrade = why ? (is this a requirement for E85?) / require retune ?
3- If flash back to run 98, injectors needed to be changed back ? / require retune ?

Sorry to be a pain - need to know / convinced.
Thanks - Tien

ID1000s are required for a tune on E85 (I suspect you could tune it for lower power and not need them, but why...) because the stock injectors don't flow enough fuel for the power levels that you can attain with E85 (higher octane, but lower specific energy than petrol, so you need to burn more of it for a given power level).

The rating on injectors is generally their upper limit - with a proper tune, good quality injectors like the ID1000s will operate fine at lower flow levels (they work through a process known as pulse width modulation). Cheap or dirty injectors may not operate well at low loads, so that's why you buy good ones and look after them (good quality fuel, etc).

[alexeiwoody]

Manaz,

Just this right ?

1- E85 = need to change fuel pump(type / cost / brand / recommendations ?) & require retune. (understood)
2- Id1000 injector upgrade = why ? (is this a requirement for E85?) / require retune ?
3- If flash back to run 98, injectors needed to be changed back ? / require retune ?

Sorry to be a pain - need to know / convinced.
Thanks - Tien

Also considering there hasn't been a single LGT on this forum that has lasted for more than 12 months after converting to E85 on the stock EJ255 - it is advisable to put in aftermarket headstuds. The stronger the better, ie something like ARP625+.

There is room to make 50% more torque on e85/ID1000s compared to 98, and across a much wider rev range. That kind of torque is serious business, especially for an engine not exactly designed to ever use e85.

Keep in mind the first sentence of this post, when getting advice from others/tuners about "but you can just tune it safely, keep power/boost down etc". It hasn't quite happened yet, and real life events speak louder than theory

[bigBADbenny]

I'd recommend doing basic reliability upgrades as above, eg pump, filters, leak checks, battery etc and a tune from eg Matt or Eric et al. Really responsive and drivable on the 9psi gate setting, nuts at 15. Logs and gauges with a btSsm...
Keep the max boost realistic and there will be headroom on 98
Apparently Matts EAT tunes are awesome

[alexeiwoody]

I'd recommend doing basic reliability upgrades as above, eg pump, filters, leak checks, battery etc and a tune from eg Matt or Eric et al. Really responsive and drivable on the 9psi gate setting, nuts at 15. Logs and gauges with a btSsm...
Keep the max boost realistic and there will be headroom on 98
Apparently Matts EAT tunes are awesome

Mmm I'm sure most people are good at eating?

[Tien GtB25]

Aha .... I knew there would be a catch ... good point about getting set up right to gain the benefits..... little worry about the reliability factor as mentioned.
For now ... she going to suck back on good ol' brew from BP. There is one around the corner of my house atm