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Just a question on your fuel economy to all your V36 owners out there.

I've got an Auto 2007 V36 SP. I always fill it with Shell V-Power (98 RON) - as in every single tank.

The absolute best/highest 'range to empty' figure I have every achieved on this car is 643km. This was achieved by driving out to the country on a highway.

So given it's a 70L-ish 'usable' tank (do I have this right?), that's 10.8L/100kms.

Now, as mentioned before this is my 'best ever'. Driving in and around the city (which is what I usually do, I live 2kms from the CBD), it reports a range to empty of around 385kms - 420kms (at worse, after filling it up) which is around 16.6 to 18.0L/100kms. Pretty woeful esp on 98 RON! My turbo R34 with the same amount of power after a few mods did better than this.

What are you guys getting?

Does anyone run their cars on 95 or 91?

Edited by Haxorz

i usually get +500km to each full tank.

I don't think we can bitch about our fuel consumption because we knew what we were getting into when we bought our cars...:down:

also, i will NEVER fill up on less than 98 octane

With my every day driving in the city, manual mode and i give it quite often i get about 380K's a tank.

I did experiment a little and for one week i drove on normal Drive mode, didnt push it much at all and I got about 450K's.

But I purchased a sports car for a reason so i started giving it again on manual mode, yes you spend a few bucks more but if i wanted to save on fuel I would have kept my Maxima.

Yeah, for sure, it's a sports car - uses fuel.

However - do we realise that our V36's are not that far off as a 2007 6.0L HSV Grange with over 300kw on 95 RON?

http://redbook.com.au/used-cars/details.aspx?R=71607 - Combined 15.2L / 100km.

Not sure how they come up with the combined figure - is it the average of hwy 10.8 and city 17.3 = (14.1L / 100km for my V36).

How can that be? (I'd imagine those manufacturer stated fuel economies hard to replicate).

Managed to get 670km on one tank from Sydney on my way back to Melbourne last year down the Hume Fwy (said I had another 50km range to go) - can't remember the L/KM average, but I know it was up above 12km/l at one point. This probbaly included about 30 mins or so of driving through Sydney traffic on the way out on the M5 too. Average speed was around 110km/h though, and since I had no number plates on the car it may of slipped higher ;)

But around home now, I seem to get about 450km in a tank - not much freeway driving, usually going 60 or 80km/h though, but I don't drive hard a lot of times, only when the moment calls for it. If I use a mix of freeways though, I can easily get 500km. It is, however, doing better than my old 2006 Maxima was, and that had VQ35DE (producing 170kW only) and a 6-speed CVT. So go figure, more power and less gears yet better fuel usage.

Oh, I forgot to mention - mine is a 370GT (i.e. 3.7L). I would imagine the 350GT (3.5L) have slightly better economy.

Thanks for your input guys, looks like I'm getting average economy. Thought I had a problem.

Damn, miss my 2.5L turbo... Economy + Power.

Does anyone know if a fuel computer would make a worthwhile difference?

Edited by Haxorz

Your first issue is don't use Shell fuel - it is junk.

ONLY use BP Ultimate, or Mobil 8000 if you can't get to a BP.

My V35 does not run well on Liberty, Shell or Caltex. I have tried them and not only do I get worse economy from those fuels, the car doesn't feel as smooth or as powerful.

For reference on a shocking tank my V35 350GT with a 65l tank gets at WORST 13 litres/100km - and that is all city driving with lots of sitting around with the a/c running. On country trips I often see 10 litres/100km or slightly better. And mine is modified and running 175rwkw, AND I always drive like they are designed to be driven - HARD!

I have only had my 370 for about 6 weeks and have only fueled up 3 times from memory but seem to be getting better fuel economy than most thus far. Since I got the car it has really only been used to drive to work and back every day down the Perth Freeway (Stuck in bumper to bumper traffic a lot of the time) and for a few trips with the GF on the weekend. I guess I don't drive like a hoon because I'm not a kid anymore, but generally I'm the one doing all of the overtaking so I don't drive like a grandma either. I only use BP Ultimate 98 Octane (in Perth it doesn't matter where you fill up as all of the fuel in every servo is BP due to BP having the only refinery here) and seem to be getting at least 550km from every tank and have not yet seen the fuel warning. I would imagine that if I drove to Kalgoorlie (600km dead straight, no traffic, 110-130 kph the whole way) that I would get there easily and wouldn't be surprised to see 700-800km from a tank. I know that my rx7 only gets 350km around town but would then get 550km on the trek to Kalgoorlie....

Maybe I am just being optimistic and because I am comparing the fuel economy to my rx7, which is WOEFUL, it simply feels like a much better range. I leave it in standard Drive the majority of the time and just switch over to the paddles for a quick squirt every now and then (or when some dick in an SS is up my ass), no point being in DS when sitting in traffic or just cruising. I have disconnected the battery when I replaced the HID's which wiped the ECU so it had to relearn the fuel consumption and it is quite amusing to leave home with 400km range showing only to drive 60km and have 420km on it when I get back :P

I am guessing that it wont take long for me to start seeing similar numbers to everyone else but at the moment the gauges show that I have done 304km and have 306km till zero so I don't know.....?

Yeah, I suppose I should mention I'm a 33 year old driver with zero demerit points (i.e. I drive spirited every now and then, but mainly sensible driving - I drive to/from work too).

Thanks Alkatraz, that's interesting info. Maybe I'll try a tank of the BP Ultimate to see if it's any different. Having spent some time in Perth though (a beautiful city I may add), I'm not sure if you guys know the meaning of traffic :) (I'm from Melbourne).

If you could crack 700km on the 'Range to empty' please do let me know as that would be awesome!

The highest I achieved was 643km (took a photo of it on my iPhone).

I just realised I made a mistake in my calculations above. My 643km max reading was after a hour of driving at 110kph, after which stage I had probably used 10 or so litres of fuel. (i.e. if I had have pulled over at that stage and put another 10 litres in it it would probably boosted the readout to over 700).

So really it should be 643km / 60L = 9.3L per 100kms Highway (or thereabouts).

That's what I get for being lazy and relying on the cars readout, many variables really.

I should really fill the car, reset the trip, drive for 500-600kms, fill up again and take note of the litres then use than figure and KMs on the trip for a true reading.

Well when I take my next trip to Kalgoorlie I will let you know. I have no idea when that may be though and I'm not sure that I want to spend $220 on fuel as an experiment lol.

Basically I think that you should only use the "range to empty" as a VERY rough guide. I reset my trip counter every time that I refuel so that I can keep an eye on the fuel usage, it has alerted me to engine issues in the past so it is a habit that I have gotten into.

BTW I am pretty sure that the physical fuel needle gauge (not sure if there is a technical word for that thing) is also directly connected to the range to empty stats and is not actually linked to any physical reading in the fuel tank. Anyone is welcome to correct me if I am wrong but I have watched the needle rise on many occasions in line with the range to empty readout. Jump in the car with the needle on half, drive 20kms on the highway and the needle can be at 5/8ths......I have never seen a car that can do that trick before.

EDIT: One more thing, does anyone know exactly how many liters of fuel are left in the tank when the Range to empty hits 0??? From memory I think I read somewhere that it is 2 liters......

Edited by Alkatraz

That's what I get for being lazy and relying on the cars readout, many variables really.

I should really fill the car, reset the trip, drive for 500-600kms, fill up again and take note of the litres then use than figure and KMs on the trip for a true reading.

That is the only way of knowing.

Also, most manufacturers design the light to come on when there's enough fuel left for about 100km of driving. After driving my M35 for 630kms, the trip computer was giving me all sorts of warnings about having to fill up, sat on '0 kms left to empty' for a while & then it gave up & shut down lol. I did over 700kms that trip & still had fuel left in the tank (80L tank). The trip computers are hardly the most accurate measure...

My 2 cents:

I've found my V35 to be quite conservative with its low fuel warnings. For example the low fuel light comes on when I still have 20 litres left in the tank (60 used) and I have usually done 430-450kms. The range til empty on the trip computer will go zero when I still have approximately 10 litres left and have usually covered 500-550kms. Most I have ever filled up was 74 litres.The V36 might be similar in that aspect - might explain why you think your economy is low, when there is still a fair reserve of petrol in the tank. As has been mentioned best way is to calculate it yourself when you fill up, although I have found the V35 trip computer to be fairly accurate.

Considering advancements in technology and claimed consumption I would certainly have thought the VQ37HR would be at least a little better on fuel than the old VQ35DE.

Oh, I forgot to mention - mine is a 370GT (i.e. 3.7L). I would imagine the 350GT (3.5L) have slightly better economy.

Thanks for your input guys, looks like I'm getting average economy. Thought I had a problem.

Damn, miss my 2.5L turbo... Economy + Power.

Does anyone know if a fuel computer would make a worthwhile difference?

The 3.7L VQ37VHR has VVEL (Variable Valve Event Lift) which improves fuel efficiency theoretically, has slightly more power and a smoother torque curve over the 3.5L VQ35HR, and also gains an extra 2 gears (5-speed vs. 7-speed automatic). Should be more fuel efficient in my understanding, but I think the 3.7L weighs more than the 3.5L (can't confirm 100% but my understanding is the 370GT weighs an extra 50kg over the 350GT in my research), has a higher compression ratio (11.0:1 in the VQ37 vs. 10.6:1 in the VQ35), basically identical 0-100 times though. Kind of hard to say if one has better fuel efficiency though, theoretically the 3.7L should be better especially cruising over longer distances and sitting in a higher gear (7th) than the 3.5L would be in 5th gear. The extra weight in the car may cause a problem though, but again not sure if that is accurate or not.

Just out of interest i wonder how far back the computer remembers to give its readings. I know that everytime I have reset the ECU it gives REALLY weird readings for the first tank before it sorts itself out.

By the time that I refilled this morning I had done alomst 400km and had 174km left till empty which showed as a tiny bit over a 1/4 tank on the gauge. Based on this I would imagine that I can get around 550km - 600km out of a tank around town with a little bit of freeway driving which would mean I should see around or over 700km if driving 100% highway, 110kph - 130kph.

Hmmm... mine's only a 5 speed auto. The 7 speed must have come later. My 3.7L V36 is a Dec 2007 build. But yes, I'd say it would cancel each other out (efficiency gain vs weight gain).

Well to confirm, here's a table showing the transmission each V36 model came out with:

Model Years Standard Optional

250GT sedan 2006– 5-speed automatic -

350GT sedan 2006–2008 5-speed automatic -

370GT coupe 2007–2008 5-speed automatic 6-speed manual (Type S, Type SP)

370GT coupe 2008– 7-speed automatic 6-speed manual (Type S, Type SP)

370GT sedan 2008– 7-speed automatic -

370GT crossover 2009– 7-speed automatic -

Edited by M34N

A "tank" is not a unit of measurement - LOL

How many liters is your fuel tank?

Fastest way to work out your approximate fuel economy per 100km.

- Fill up your fuel tank to full.

- Reset your trip meter to zero

- Drive etc.

- Next time you fill up *make sure you fill up full tank* note how many KM you have driven and note down how many liters you have filled.

(number of liters divided by number of KMs you have driven) X 100 = avg fuel consumption per 100KM

To economise on fuel for FWY/HWY runs, if you keep the speed around ~95km/h you will get massive fuel savings, reason being wind resistance becomes an issue from roughly ~100km/h+

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