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I don't get to drive my toy much but noticed soon after buying it that it was VERY fuel inefficient. When I say very, I mean absolutely appauling. People say yeh it's because you drive a GTR with aftermarket turbos, well yes, average fuel consumption is somewhat expected, but I am only getting 180-190 km per tank!!! It's actually laughable (and cryable for my wallet!). What mileage is everyone else getting? Please state your engine, ECU, turbos, and injectors as follows:

Engine: RB26DETT

ECU: Apexi Power FC D jetro

Turbos: Garrett -5s

Injectors: Sard 800 cc

Cheers.

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RB26DETT

PFC, nismo AFM's

-9's

555cc

Around town, 400-420km

Hwy 100-110km, 550km

I use 5th at 60-80km and 6th over 80km.

Some people I've noticed use the wrong gear for the speeds they do, ie 3rd gear at 60km..... you think they just want to be ready to boost off or something.

All you do is wear engine quicker and use a gut load more fuel.

There is using the wrong gear like 5th at 40km/h up a hill, but come on!!!

O2 sensors seem to be a common culprit, and also lazy tuners that don't spend some time tweaking the light load/cruise map, and you end up with poor fuel economy.

Shouldn't matter what size injectors that are used too. I think ecomony matters as it = more fun km per tank :D

And Michael, geez that is like E85 fuel economy!!!! That ain't right!!

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RB26DETT

PFC, nismo AFM's

-9's

555cc

Around town, 400-420km

Hwy 100-110km, 550km

I use 5th at 60-80km and 6th over 80km.

Some people I've noticed use the wrong gear for the speeds they do, ie 3rd gear at 60km..... you think they just want to be ready to boost off or something.

All you do is wear engine quicker and use a gut load more fuel.

There is using the wrong gear like 5th at 40km/h up a hill, but come on!!!

O2 sensors seem to be a common culprit, and also lazy tuners that don't spend some time tweaking the light load/cruise map, and you end up with poor fuel economy.

Shouldn't matter what size injectors that are used too. I think ecomony matters as it = more fun km per tank :D

And Michael, geez that is like E85 fuel economy!!!! That ain't right!!

Yeh I know!! I spoke to Chris at Racepace and he tells me the injectors I've got are one culprit as is the PFC d'jetro which inherently has to be run richer. I get a buttload of unburnt fuel literally spitting out of the exhaust at idle :/ Apparently the guy who tuned it in Tassy wasn't familiar with the power FC (which is clearly evident) or confident in tuning it, but I didn't think it was possible to have THAT bad of a fuel economy.
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See if its still running 02 feedback if you have a hand controller for your Power FC. If so then it could be your 02 sensor(s). I'm not sure how they work in the GTR's (There's 2 of them in a GTR right?) so if ones stuffed and ones good I dont know what this would do to the cruise AFR's

If 02 feedback is off, Then its possible that your cruise AFR's werent tuned or werent tuned properly. I have mine tuned rather then running 02 feedback because I can run it slightly leaner at cruise AFR's. The Power FC, I think aims around 14.5:1

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I've had PFC D Jetro on this one and the previous > both gave me 400+Km/tank ie more accurately 14.5l/100Km and a bit more with squirts (but not peak hour traffic)

State of tune was tops on both cars.

Both run 600cc Sard

Both run -7 or N1

Methinks your consumption is excessive, so 02???

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I don't get to drive my toy much but noticed soon after buying it that it was VERY fuel inefficient. When I say very, I mean absolutely appauling. People say yeh it's because you drive a GTR with aftermarket turbos, well yes, average fuel consumption is somewhat expected, but I am only getting 180-190 km per tank!!! It's actually laughable (and cryable for my wallet!). What mileage is everyone else getting? Please state your engine, ECU, turbos, and injectors as follows:

Engine: RB26DETT

ECU: Apexi Power FC D jetro

Turbos: Garrett -5s

Injectors: Sard 800 cc

Cheers.

as i ask in every fuel economy thread like this, how many Litres are you calling "a tank"? without this we can't tell whether you just have bad economy, extremely shit economy, or a dodgy fuel gauge

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A full 34 GTR

as i ask in every fuel economy thread like this, how many Litres are you calling "a tank"? without this we can't tell whether you just have bad economy, extremely shit economy, or a dodgy fuel gauge

A full 34 GTR tank which i think is 50L??? I think you could definitely regard it as extremely shit economy - Its about 23L/100 km :/
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Just to rub it in a bit more I got 404kms today on 48L so 11.9/100 and that included an hour on the dyno which spent quarter of a tank on the gauge.

Was going to get wideband to tune for economy but don't think I will bother.

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A full 34 GTR

A full 34 GTR tank which i think is 50L??? I think you could definitely regard it as extremely shit economy - Its about 23L/100 km :/

It's a 65 litre tank, but I have managed to fit in 55 litres when the fuel light was on for a while..... :whistling:

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If the economy is that bad, you may as well switch to the E-flex and retune with a better tuner...

I was getting 450km average on 98

now getting 300-350km out of E-Flex

when the light comes on i have about 10-15Litres still in there, have measured 10Litres when its below the empty line..

Edited by SliverS2
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Do you have a copy of your d-jetro map that you could email me? ian @ isit.net.au

I use a d-jetro and see around 180-200km/tank if I drive like a nutter. Best on the open road is close on 8-8.2lt/100km now.

Have you adjusted your cam timing with gears? If so, what are your new settings.

What is your cruise speed and gear generally...?

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You guys have me starting to worry about fuel economy because at best I get around 15l / 100km and it is not difficult for it to drop to around 21 or 22 when you really start to push it.

I still have the original o2 sensors in the car so it looks like they probably need replacing.

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