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Hi all, is this normaly for a r32 rb20det to drink so much fuel.. i put 35L and only got 200km out of it and did not thrash it much and its got a tacho for air/fuel mix and it always goes to rich when i put my foot down.

***mods***

-turbo off R33

-mines ecu

-front mount

-3" turbo back exhaust

-boost on 10

-BOV

thanks for any help, please let me know if its normaly to be wasting that much fuel cause of the mods it has.. or is it bad??

Cheers

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AFR guages are useless....just for looks, dont really serve a purpose as when you put your foot down the ecu goes into closed loop mode (i.e. does not use the 02 sensor to figure out the rite AFR it just uses its Air flow meter reading and calculates exactly how much fuel it needs). The 02 sensor is for lite throttle tuning for the ecu. Im assuming its hooked up to the 02 sensor like every other one iv seen.

Turbo motors are tuned this way (when you put ur foot down) in order to keep detonation down. Turbo motors are more prone to detonation than N/A engines and hence adding more fuel reduces the amount of detonation. Hence when you put your down the AFR guage goes straight to rich.

As for you economy...i get anywhere from 400km-450km from a tank (60L). So from 35L thats about rite. I wouldnt be complaining.

put it on the dyno and see what afr its really pushing (my bet in the 10's despite the "mines ecu"), and those gauges are as useful as tits on a bull (unless its a proper wideband)

get it tuned properly, you'll notice a massive difference in ecomomy and power

It actually goes into OPEN loop mode when you put your foot down. CLOSED loop is at idle or cruise (vacuum) and uses the O2 sensor output to regulate fuel input.

I also get similar consumption as you.

Edited by bubba
The 02 sensor is for lite throttle tuning for the ecu. Im assuming its hooked up to the 02 sensor like every other one iv seen.

Turbo motors are tuned this way (when you put ur foot down) in order to keep detonation down. Turbo motors are more prone to detonation than N/A engines and hence adding more fuel reduces the amount of detonation. Hence when you put your down the AFR guage goes straight to rich.

I run wideband, and the engine stays closed loop (14.7:1) even on light boost. So - shouldn't go straight to rich.

I also get ~ 10lt/100km despite caning it, but I am running a 3.7:1 diff and the car only weighs 1090kg.

It actually goes into OPEN loop mode when you put your foot down. CLOSED loop is at idle or cruise (vacuum) and uses the O2 sensor output to regulate fuel input.

I also get similar consumption as you.

Sorry my bad...shud have referenced my engineering textbooks for that one (i struggle to remember the course after i pass it!) haha...indeed it goes to open loop when you put your foot down, i.e. it doesnt use the 02 sensor to regulate the fuel requirements....but when on light throttle it goes into closed loop mode.

I run wideband, and the engine stays closed loop (14.7:1) even on light boost. So - shouldn't go straight to rich.

I also get ~ 10lt/100km despite caning it, but I am running a 3.7:1 diff and the car only weighs 1090kg.

Im not talking as in the second u put ur foot down, but as soon as boost and revs begin to wind up a bit (4000RPM +) it will wind out to rich...

As for you economy...i get anywhere from 400km-450km from a tank (60L). So from 35L thats about rite. I wouldnt be complaining.

Ok thanks mate, its my first turbo car so i dont know much about them but i dont mind if its alco on fuel :( cause there fun to drive and its worth it.

Thank you.

I got 495kms from 59litres of fuel in rb20det A31 the other day. Sedate driving. Rarely going past -0.2 bar vacuum on the boost gauge. So try to control your right foot and you can get even better economy.

Edited by robots
brothers rb20det r32 gets around 9-10L / 100km's. his runs rich (dyno to indicate this). so i think your economy is out the window, something is most likely wrong

I think your right.. because even my mates say my car wastes heaps of fuel even if i dont thrash it still drinks to much compared to there cars.. so i will take it to the mechanics tomorrow and see what they say.

Thanks everyone for your time.

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