1jz fuel economy

[mullett]

VVTi 1JZ stock ECU in an RA23 got about 9-10litres per 100k on a trip,(Canberra to Dubbo) and anywhere from there to 15 litres per 100k when having some fun.

The low down pulling power is a characteristic of the VVTi.

cheers Chuck.

Yup, that's about what I'd consider 'normal' fuel economy. I've spent a fair bit of time in an XR6T, and that uses 10ish on a highway run without hanging around, and about 13ish in the city. So to me, anything worse than that is a problem...I mean, the thing weighs 1.7tonne!

-RM.

[J0RD0]

so you'd think a 2.5ltr engine in a 1100kg car would be getting at least 10l per 100k????

[mullett]

You'd think so, huh...the MR2 (standard except for intake, exhaust and 12psi pulley) averaged dead on 10L/100km, and it got driven pretty hard. I never exceeded that except for track work, and got down to 6L/100km on a VERY gentle country run (90km/h following a friend with a trailer and cruise control )

With cams, SC14 and a water/air cooler, and most notably an aftermarket ECU, it shot up to 12-13L/100km. Considering that most of the mods would have made it more efficient, and i was driving it in a similar fashion, I'm pretty sure most of the blame lies with the ECU/tuning. The transition from SC on to SC off also made it difficult to tune. I didn't expect it to get that bad, especially given that the standard ecu ran EXTREMELY rich on boost, like 10:1 or worse AFRs.

-RM.

[The Real Roadrunner]

brisbane turbo and tuning, forgot to mention the tuned it without a tps and it is map sensored. The tuner also complained it was hard to tune with the auto/torque convertor at low revs. Sometimes on really light throttle its hesitates and drops revs.

Hook the TPS up and take it to somone who knows how to tune it properly. the light load tuning cant be that hard to get right especially if its essentialy a stock setup.
you should get easily 13L/100 around town with the motecs functions.

cheers
linden

[zombie]

I get between 450 - 550 km from 60L in my JZA70, stock ecu

[Aust162]

I get between 450 - 550 km from 60L in my JZA70, stock ecu

^^Thats dam good! wondering what the hell is wrong with my jza70?! I'm getting 300ish from a tank

[J0RD0]

driving style?

[richzx]

The earlier JZX ecu's just aren't as efficient as the later ones. I've gone from mx83 with stock JZX81 ecu with an exhaust and I/C to exactly the same thing except no I/C in my JZX90 and the '90 gets WAY better fuel economy around town and they both do 10-11L per 100km on the highway. I put it down to the better ecu in the JZX90 compared to the JZX81, which is the same as the JZA70.

[lexsmaz]

My old Corona 1JZ standard computer & injectors etc, 10 psi boost, ( 199 rwkw so was no slouch ) but running a manual, used to return 10L / 100km basically all the time ..

I now have a stock Auto JZZ30, getting around mid 11 to mid 12L per 100km light city traffic, reasonably light throttle, but certainly no Nana driving though ..

[BrianRA23]

I know my friends JZX101 with the 1JZGTE VVTi engine used to get 10km/L around town with 70% on the freeway. Much better than the Cressida with JZX81 conversion I owned at the time.

Based on his experience I was considering using the 1JZGTE VVTi auto in my next car. The torque that engine as at all revs is impressive and its efficiency impressed me. I want it for a comfortable daily driver so I think I should be happy with the standard turbo etc.

What controller do you have for the auto? You mentioned the guy had trouble with tuning due to the auto, and I have read the Suprastick will allow you to lockup the torque converter for dyno setup and testing. Could you not lock it up for him?

On my Aristo, using a WB02 kit and display and intercepting the MAP signal to the ECU with a DFA I have made it much leaner for low loads. I used to get about 600km from a tank 70L or 80L and after the setup, I did 365km of highway driving at 115km/h with more than a dozen overtakes getting up to 150km/h. This included about 20km on gravel, through a hilly twisting road and up the Darling ranges to Collie, from the coastal plains of the south west. This used 38L (calculates to 10.4L/100km). Without the aggressive overtaking and working it through the hills this could/should drop down to and below 10L/100km quite easily.

That is the long way as saying you should be able to get better economy, if the tuning was right. Is the VVT connected and working?

[SL666]

i get ~270km to 45L in my 1j lux - but i'm a bit heavy footed.

300km/40l in an evo? and you are being nasty? erm no.. no you aren't. lowest i ever got out of mine was 180km/45L - but i may have used the pedal on the right occasionally.

[EldarO]

^^Thats dam good! wondering what the hell is wrong with my jza70?! I'm getting 300ish from a tank

nothing.

thats normal!

ive gotten 450k's out of a tank by driving it like a grandpa, but wheres the fun in that.

[zombie]

nothing.

thats normal!

ive gotten 450k's out of a tank by driving it like a grandpa, but wheres the fun in that.

only time I drive like a grandpa is the very last leg of the journey home (eg take it nice and easy on my street )

[J0RD0]

What controller do you have for the auto? You mentioned the guy had trouble with tuning due to the auto, and I have read the Suprastick will allow you to lockup the torque converter for dyno setup and testing. Could you not lock it up for him?

Is the VVT connected and working?

its a manualised shift box with seperate overdrive and convertor lock up switches


Yes the vvt is working

[auto351]

My problem is its getting on average about 230 - 280ks to a 45ltr tank, i did a run just putting it around which was very hard to do with an almost no lag and got around 320ks to a tank

Just thinking if your starting data is good, something which will effect my readings in the past were, speedo out of calibration - (due to diff conversion)& bad fuel reading, when I meusred my fuel level I did one fuel fill and got poor reading , but when I did the mesurements over 4 fuel fills my results improved. but my main problem was the diff ratio error.

Manuel.