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Stock Rb25det Fuel Economy?

b1ancardi
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soviet_merlin Experienced

soviet_merlin

Posted
Posted
2 hours ago, Dose Pipe Sutututu said:

Time for a modern ECU with wideband O2 and closed loop O2 strategy.

Do you have any numbers on how much of a difference it makes? I would think driving style makes the big difference for fuel economy but that's just gut feeling.

I would also like to think that as long as the setup is healthy for the engine, good fuel economy is really not a goal for cars like this. Or maybe that's how I justify it for the wagon. I also blame turbo noises and the exhaust going brpbrpbrp when letting off the throttle at higher rpm in lower gears.

Staff at the gas station are always very welcoming. I'm probably financing their kids' education.

Getting fuel more often also seem to make it hurt less. For whatever reason spending $60 on half a tank feels very different from spending $120 for a full tank.

Murray_Calavera Mentor

Murray_Calavera

Posted
Posted
2 hours ago, soviet_merlin said:

Do you have any numbers on how much of a difference it makes? I would think driving style makes the big difference for fuel economy but that's just gut feeling.

Just driving around town normally, which involves being on boost as often as possible without driving like a dick, I get around 10L/100KM on 98. I'm running a Haltech pro plug in, ID1050X injectors, 60mm turbo. 

Fuel map is what you'd expect to find with one difference, the very very low load areas (think like 1% or 2% open throttle) I run those parts of the map quite lean, around 16AFR. Oh and the idle is set to about 600 rpm. 

To answer your question, about 30% saved on fuel?

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Dose Pipe Sutututu Grand Master

Dose Pipe Sutututu

Posted
Posted
2 hours ago, soviet_merlin said:

Do you have any numbers on how much of a difference it makes? I would think driving style makes the big difference for fuel economy but that's just gut feeling.

no back to back numbers, however with wideband 02 closed loop, you're always correcting fuel regardless of the load you're at (depending on how you've set the closed loop strategy to work) not to mention the rate of change/correction is much faster than say a PowerFC or stock ECU.

Also with an aftermarket ECU you can command you cruise at say 15.2:1 instead of 14.7:1.. instant fuel savings there.

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robbo_rb180 Grand Master

robbo_rb180

Posted
Posted

12.8-13.2l per 100km on e85 on a 3000km roadtrip.

I use a 4d fuel map that leans out at light throttle cruise 4-12% tps at 1500-2400rpm. Improved economy and didn't ruin the VE fuel map with silly dips.

Yet to run 98 as car rarely is driven

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