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ok 2 things,

first: USE THE FUCKING SEARCH FUNCTION!!!!!!!!!!!!!!!!!! sorry but this has been covered 432.6 million times already on this forum and about every week a new fuel economy thread pops up.

secondly: "a tank" is not a unit of measure unless you are running it until the car stalls then filling up to the top. unless you post up how many litres you are actually putting in we will not know if you are getting shit fuel economy or have a dodgy fuel sender or if you consider just under half a tank to be empty. to find out if you have bad economy, reset the trip meter next time you fill up, then the next time after that when you fill up divide how many litres you have used by how many hundred kms you have done and then you will get a fuel economy reading in L/100kms. the higher the number the worse it is.

for example, lets say you used 45L to do 368km

45 diveded 3.86 (because you are diving by lots of 100kms, not just kms) = 12.22L/100kms

as to give you an indication of what is good, and what is bad, for highway/motorway driving anything down around 10 is good. for city driving, 13 or so is good. i was getting around 17L/100kms but i am a leadfoot and the type of driving i was doing wasn't going to allow me as good fuel economy as some others even if i wasn't a lead foot. on long trips though i was getting around 10L/100kms. if you are getting 13 or 14 from highway driving, get a new o2 sensor (again, sarch for info on that). also the more time you spend boosting up when acceleration, the more fuel you will us. accelerate a bit easier and keep the boost lower and you will use less fuel.

petrol has energy in it that burns to make powahhh :) if you get 17l/100km from a standard rb25 thats bad. if your making 11ty kw then 17l/100km seems reasonable. as mad said, info please :)

Sorry to hijack your threat, but thought i'd ask how many of you guys fill up with premium? Cuz ever since I bought my 33 I've always used premium only.. Infact (this is stupid and you're more then welcomed to say how dumb I am) I don't actually know if I'm allowed to use reg for turbo..

Sorry to hijack your threat, but thought i'd ask how many of you guys fill up with premium? Cuz ever since I bought my 33 I've always used premium only.. Infact (this is stupid and you're more then welcomed to say how dumb I am) I don't actually know if I'm allowed to use reg for turbo..

I always use premium, with regular (91RON) it pings too much.

'Around town' driving, which includes a lot of pointless boosting and acceleration :), I'm using around the 13-14L/100km mark... just went on a road trip to Sydney on the weekend, so lots of 110km/h cruising, and averaged about 10.8L/100km.

Sorry to hijack your threat, but thought i'd ask how many of you guys fill up with premium? Cuz ever since I bought my 33 I've always used premium only.. Infact (this is stupid and you're more then welcomed to say how dumb I am) I don't actually know if I'm allowed to use reg for turbo..

don't ever fill up a turbo car with 91. that's bad, mmmmkay. so you are doing the right thing by only using premium. even running it on 95 octane premium isn't the best idea. they are designed to run on high octane fuel from factory, and running it on lower can make them run poorly as also cause damage if done long term.

cefiro gets 9km/l (95 octane, stock RB20DET)

r32 gets 6 km/l (98 octane, modded RB20DET)

camaro gets 4 km/l (91 octane, err 5.7l V8)

i looked at that and thought WOW. then i realised it was KM/L and not L/100km

so in L/100kms you are using:

11L/100km

16L/100km

25/100km

wow that's some errr... impressive fuel usage by the camaro. i'm guessing it's an old carby 350 then?

bah! you guys need RB20's... im getting 11L/100km (city) and im a bit of a lead foot.

And you need some torque muhahahaha.

OP as Marc said it's the length of a piece of string depending on your vehicle and perceptions. It has also been covered many times before. I'll be nice and suggest that your fuel economy sounds pretty shit anyway. Replace the oxygen sensor if it hasn't been replaced in the last 50,000km or if you have no history of it being replaced. Will make a significant difference to mileage. I average about 12.8-13.2 L/100KM suburban driving and I spend a good deal of time on boost.

also what some people class as city driving is totally different to other peoples city driving. for example some people might drive through the city on a motorway at 80 or 100kmh for half of their trip and the rest might be on a 60kmh road where you go for ages without stopping at trafic lights or anything like that. that will give much better economy than someone who has to drive along a stretch of road where they have to stop lots. both driving in the city yet 1 person is going to get much better economy than the other. a prime example of this is my drive to work. i have to stop as much as 6 times in 2km in the worst case scenario, but even on the best case scenario i'm still accelerating 5 times from turning at intersections, 2 of which are up hill and close to home so the car is still cold and running richer. coming home from work i have to accellerate up a long hill not far from the carpark. plus it is such a short trip that even if i drive like a granny i'm never going to get as good fuel economy as other people who drive further to work than me and have better routes where they don't have to stop as much.

what model is it? brother-in-law used to have an old z28.

Gen 2, 1973 body, not sure on spec, its a bit of a Frankenstein... doing a resto on it atm.

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