The Truth about L Series Fuel Tank Capacity (RX Sedan) and E10 fuel .

discopotato03 · Post by **discopotato03** » Wed Jul 16, 2008 5:18 pm

Hi all , I have a keen interest in Ethanol/Petrol blends and decided to give E10 a whirl for a week which equates to ~ 550- 600 Km .
The E10 I'm using is not from a big name chain and I only stumbled on it about a fortnight ago in a running out suitation and tossed a small amount in just to get me by .

The Diet Coke RX liked it so much I decided to give it the full tank test mainly to see if the consumption was line ball or worse than the Caltex Vortex 98 I had been using .
For the last day of the week I carried around 12L of juice because Ellie was getting low and I wanted to see at least 600 on the odo before filling it up .
I drove it as far as I was game to ie the fuel gauge needle just falling off the bottom of the "E" - stop laughting - and couldn't believe it was still firing .
I was also keen to see once and for all how much fuel its possible to squeeze into an early RX L sedan .
For those interested in the numbers the odo read 616 , bowser read 61.52L and unfortunately $96.90 so $157.5 per liter .

From this I've learnt that the tank will hold at least 60L , the gauge falls 6-7 liters further than I thought it would , consumption appears to be the same at ~ 10L/100Km , fuel prices are disgusting , no low fuel light .

I'm interested to see if advancing the ignition timing a bit will make it go any better or give a few more MPG .
Also if I can get hold of some low water content ethanol I'd like to see if "E15" does any better again .

As you may have guessed I really like the idea of ethanol blended fuel mainly because of its high octane rating (105-110) and it costs a fraction of the price of unleaded race fuel . It also doesn't come out of holes in the ground in foreign places .

Will start a new thread on ethanol in automotive fuel , cheers A .

Gannon · Post by **Gannon** » Wed Jul 16, 2008 6:13 pm

Ive been using E95 for ages. It is 95 octane rated and its half a cent cheaper than 91 octane unleaded. Doesn't sound like much, but thats about 7-8 cents cheaper that Vortex 95.

If i drive like a normal person i get about 370-400km for a 40L fill up. I always fill it up to click off, but it takes 40L till the gauge reads empty (which means i always have nearly 20L spare incase i cant fill up in time)

Mind you, if i drive like a teenager, i can get as little as 300Km to a 40L fill up.

YouTube · Post by **El_Freddo** » Wed Jul 16, 2008 9:54 pm

discopotato03 wrote:For the last day of the week I carried around 12L of juice because Ellie was getting low and I wanted to see at least 600 on the odo before filling it up .
I drove it as far as I was game to ie the fuel gauge needle just falling off the bottom of the "E" - stop laughting - and couldn't believe it was still firing .
I was also keen to see once and for all how much fuel its possible to squeeze into an early RX L sedan .
For those interested in the numbers the odo read 616 , bowser read 61.52L and unfortunately $96.90 so $157.5 per liter .

From this I've learnt that the tank will hold at least 60L , the gauge falls 6-7 liters further than I thought it would , consumption appears to be the same at ~ 10L/100Km , fuel prices are disgusting , no low fuel light .

I coulda told you about the fuel tank - I'm sure I posted it a while ago. My MPFI drove from adelaide to woodend on one tank - 730 km to 62 L - with the car still running! All of this trip was at cruising speed, some flat foot overtaking but was not normal "stop, start" city driving...

I was also dissappointed to find no fuel light either, I thought the L series had one.

Also I don't know if advancing the timing will effect performance on E10 fuels as the MPFI and MPFI turbo ECU should compensate for this. It would be interesting to do a comparison of fuel consumption on E10 between the MPFI and MPFI turbo EA82. I never found a performance gain with the ethanol fuels and never had a drop off either with my driving...

Cheers

Bennie

LTurbo · Post by **LTurbo** » Wed Jul 16, 2008 10:42 pm

I am quite sure my L-series (4auto rx) has a fuel light, and I would have assumed all L-series had them. Strange, even my MY had a fuel light.

Post by **Captain Obvious** » Thu Jul 17, 2008 5:49 am

my rx had a fuel light, didnt work untill i found 3 or so wires in the back right quarter panel that some wernt connected, connected them and fuel light worked.

if you read the book most car will say when the light comes on there is 7-9 lirtes left in the tank.

bryan

Suby Roo · Post by **Suby Roo** » Thu Jul 17, 2008 8:44 am

My old L series never had one, Had the dash pulled out and everything and there wasnt anything there.

AndrewT · Post by **AndrewT** » Thu Jul 17, 2008 8:50 am

Was there some mystery about the fuel tank size or something? The fact that I own one of these cars and strangely enough frequently put petrol into it means I have a pretty good idea of it's capacity. I think they are advertised as a 55L tank but you can squeeze an extra 5 or 6 litres in if your keen.

Out of interest when running mine on 95octane fuel (sometimes I use 95, sometimes 98) I get around 550kms from a fuel tank down to near-dry - EJ20G with standard boost and turbo.

Thalass · Post by **Thalass** » Thu Jul 17, 2008 10:15 am

I didn't know ethanol had a higher octane rating... Would it be possible to use E85 on a newer suby that was meant to run on premium? Not that we have E-anything at the local petrol station.

steptoe · Post by **steptoe** » Thu Jul 17, 2008 11:58 am

and if posted capacity is 55 litres (isn't that the Brumby alleged capacity ?) , from memory (a post in here may have the detail) I ran out, *cough * cough splutter, not safe to drive on at 52 litres to refill in my 3/87 sedan auto turbo with the same sort of economy you have A. - with the 3 peed auto in different driving conditions though I suspect

AndrewT · Post by **AndrewT** » Thu Jul 17, 2008 3:35 pm

How's this for a topical photo

The RX was due for fuel this morning but I decided to stretch it out further....ran it down till the needle was well below the E, fuel light was on for about 50km...

I had to trickle it in very slowly towards the end to stop the bowser clicking off.

(by the way, this servo must have a pretty old invoicing system, it was NOT "super" fuel I put in, just their premium unleaded).

BRUMBI · Post by **BRUMBI** » Thu Jul 17, 2008 4:21 pm

my rx has no fuel light and the most i have got in it was 63lt

Gannon · Post by **Gannon** » Thu Jul 17, 2008 5:26 pm

I had a DL (non tacho) dash in my car and it didnt have a fuel light. My tacho out of the Touring Wagon with the tacho has a fuel light, but ive never seen it on.

AndrewT · Post by **AndrewT** » Thu Jul 17, 2008 6:35 pm

the Monsterwagon (1989 MPFI touring wagon) appears to have one, can see a little squarish rectangle there, but I've also never seen it lit up. I've run the wagon down to basically empty too. Maybe it's LED is blown or perhaps the window is there but no actual light.

fredsub · Post by **fredsub** » Fri Jul 18, 2008 10:31 am

on me old L series, the needle goes below 30deg of the E before engine stops.

yeah $100 now to fill the bloody tank:mad::mad::mad:, why is that we need price parity? oh its not collusion if the gov sponsors it:mad:

discopotato03 · Post by **discopotato03** » Fri Jul 18, 2008 12:02 pm

I'd be very wary of running E85 in anything not tuned to run that much ethanol . Having said that V8 Super Fart series cars use it but they are tuned specifically to run it and cost is not an issue . I think Saab is just releasing an E85 car for well heeled green people (Einsteins who've worked out that Pius and the like are a joke) and Holden is developing models that can run it as well . On the LS1 Edit site they claim that later LS1 (5.7L V8) computers already have E85 Maps in them but are not enabled .

My next experiment (as mentioned to one in a PM reply here - the Industrial Chemist fella) will be to get a smallish volume of E85 and dump it in next time Ellies virtually empty . I think the numbers work out to be approx 4L of E85 is about 3.4L of ethanol so tossed in "th hole" and then filled up with my now usual E10 gives about E15 .

I look at it as 10% of 60L being 6L , 15%-9L, 17.5%-10.5L , 20%-12L .
As was mentioned ethanol alcohol with very low or no water content is difficult to find but 85% ethanol 15% ULP (E85) not and easy to buy and carry in small volumes/containers . My fuel container is 11.5L so I could get near to E20 when mixed into E10 .

There are only two points for any of this ethanol blend business and they are to a limited degree cost (atm in lowish percentages) and greater octane .
Higher octane is only of any benefit if you can advance the ignition timing for best mean torque everywhere whilst maintaining the correct air fuel tatios .
Running higher octane straight petrol than is required gets you nowhere , actually high octane straight petrol is more difficult to ignite than low octane stuff and it's this that makes it more detonation resistant . Low octane fuel makes great power because it burns faster , it's the retarded ignition timing to prevent detonation that costs power .

If you can use low octane fuel with detonation resistant ethanol blended into it cars that detect detonation (knock sensors) won't dectect as much and therefore won't retard the timing as much .

Next flurry of research will be into how much larger injectors to run for if/when E10/15 etc is available everywhere so the AFR's can keep up .

Cheers A .

colwyn · Post by **colwyn** » Fri Jul 18, 2008 1:13 pm

I've run My RX trubo with the E10 Stuff from United Petrol for a while now and I notice I can run 15 pounds of boast with no pinging, only 8 with standard petrol. So I have a switch for both fuel types.

Wilbur · Post by **Wilbur** » Fri Jul 18, 2008 2:06 pm

My old RX had an idiot light for the fuel, but it was real heavy on juice. Worst I ever got was about250km from a tank

discopotato03 · Post by **discopotato03** » Fri Jul 18, 2008 8:14 pm

Well I made the decision this afternoon to head over to Rozelle with a couple of fuel containers and bring back some of this E85 . Man does this stuff smell goooood . I can only hope it puts Ellie in a friendly mood , it's actually too full to get any worthwhile amount in ATM so when I can squeeze 4L in and top up the usual E10 brew I'll get back on how it likes E15 .

The LS1 Edit site mentions that the exhaust smell changes when burning E85 , not that we want to be sniffing exhausts !

Cheers A .

Gannon · Post by **Gannon** » Fri Jul 18, 2008 9:38 pm

Ive noticed that my exhaust smells a little metho'y when usung the E95

steptoe · Post by **steptoe** » Sat Jul 19, 2008 10:01 am

on the idiot light issue. my L has two wires that were both happily corroded away in their white plastic disconnector way down in the rhs well of the boot. Clean up and repair of both still did not make said light work. I have always thought all red dash warning lights should have a BUZZER included

and it is 60l in the sube manuals for L series tank capacity, so yeah I was curious as to why about seven litres being unavailable - keep pump wet p'raps ?