L/100km Before And After The "chip"

[ITINT]

The values I quoted above are from the trip computer.

But I also maintain a separate spreadsheet (I'm anal retentive remember!).

The spreadsheet indicates prior to chipping 11.2, now 11.0 l/100kms.

So, I'm different to the experiences of both ITINT & BLKXRT

56 Mainline my experience is similar to yours. I gained a 5 % decrease in fuel consumption with just a Unichip fitted. Early indications with the Phase 2 kit are 2-3% better on my regular highway trip to Melbourne.

As with BLKXRT however, my trip computer is showing about a 25% decrease in the consumption (as mentioned in my previous post). It does seem pretty clear that a correctly installed and tuned chip not only gives some serious KW gains but will also enable better fuel consumption..... if you can restrain yourself from using the extra horses all the time.

[F6 RAPID]

Yep, I have heaps more grunt with Chip Torque Xede, rampod and no centre muffler and now averaging 14.4l/100km. Trust me, I am a leadfoot. This figure includes commuting, freeway work and cruising at 160-170 km/hr with my motocross bike in the back (I was late!) for 120kms.

Much better fuel economy!

[Guest Big Mick]

Sorry to bring up an old thread, but I have been searching for some info on the accuracy of the trip computer after an injector upgrade.

There is no flow meter in the fuel line, so I believe the trip computer calculates the fuel used based on the duty cycle of the injectors (for a constant fuel pressure). Thus if you increase the injector capacity by 25%, you could expect to see a 25% decrease in the duty cycle of the injector (all other things been equal) to achieve the same AFR. Thus the trip computer thinks you are using less fuel.

Hope this hasn't already been stated somewhere else.

Mick

[Guest LOK@ChipTorque]

Sorry to bring up an old thread, but I have been searching for some info on the accuracy of the trip computer after an injector upgrade.

There is no flow meter in the fuel line, so I believe the trip computer calculates the fuel used based on the duty cycle of the injectors (for a constant fuel pressure).  Thus if you increase the injector capacity by 25%, you could expect to see a 25% decrease in the duty cycle of the injector (all other things been equal) to achieve the same AFR.  Thus the trip computer thinks you are using less fuel.

Hope this hasn't already been stated somewhere else.

Mick

Good question Big Mick.

The actual answer will depend on what injector (specifically what dynamic flow rate far more so than static flow rate) but, the piggyback systems all reduce the apparent load signals to the PCM so that it delivers less fuel. It will normally show a percentage improvement in fuel consumption which is not all real for the reasons you observe. Some of the improvement is real and related to the ignition and cam timing changes. The rest would be fictitious and is related to the PCM's response to the change in dynamic flow rate at low duty cycle which may be vastly different to the 25% change you suggest. It may only be 2-3% depending on what injector.

Hope the long answer clarifies it a bit.

Lachlan

[Guest Big Mick]

Good question Big Mick.

The actual answer will depend on what injector (specifically what dynamic flow rate far more so than static flow rate) but, the piggyback systems all reduce the apparent load signals to the PCM so that it delivers less fuel. It will normally show a percentage improvement in fuel consumption which is not all real for the reasons you observe. Some of the improvement is real and related to the ignition and cam timing changes. The rest would be fictitious and is related to the PCM's response to the change in dynamic flow rate at low duty cycle which may be vastly different to the 25% change you suggest. It may only be 2-3% depending on what injector.

Hope the long answer clarifies it a bit.

Lachlan

Thanks Lachlan, that indeed clarifies the matter even further.

Mick

[igsta]

In standard form the car runs rich to protect itself from damage. Im just curious in the engine life span the chiped cars would have over the standard ones as the chips lean out the mixture not protecting the motor as much.

[Guest Big Mick]

In standard form the car runs rich to protect itself from damage. Im just curious in the engine life span the chiped cars would have over the standard ones as the chips lean out the mixture not protecting the motor as much.

How lean (or rich) the AFR becomes depends on the tuner and is not directly related to the use of a chip. Chips are also able to modify ignition timing and boost to increase power.

While a lean AFR will generally make more power when compared with a rich AFR, a good tuner will always build in a safety margin for the AFR. You also need to remember that the factory tune is calibrated for the wide tolerances that occur in engine building. A good tuner effectively "blueprints" the engine tune to your specific engine.

Therefore, the engine life span of correctly tuned chipped car would be more affected by maintenance such as oil and filter changes, than it would be by the installation of a chip.

[aps]

In standard form the car runs rich to protect itself from damage. Im just curious in the engine life span the chiped cars would have over the standard ones as the chips lean out the mixture not protecting the motor as much.

How lean (or rich) the AFR becomes depends on the tuner and is not directly related to the use of a chip. Chips are also able to modify ignition timing and boost to increase power.

While a lean AFR will generally make more power when compared with a rich AFR, a good tuner will always build in a safety margin for the AFR. You also need to remember that the factory tune is calibrated for the wide tolerances that occur in engine building. A good tuner effectively "blueprints" the engine tune to your specific engine.

Therefore, the engine life span of correctly tuned chipped car would be more affected by maintenance such as oil and filter changes, than it would be by the installation of a chip.

Big Mick, Good post and there are other variations in the car/engine combination that custom dyno tuning improves. The fact that fuel pressure varies from being perfect to low or high, and that turbo pressure is not identical on every engine means that custom tuning via an interceptor style computer allows the engine to be tuned to perfection and without compromising engine durability, if a safe and practical tuning strategy is adopted

Peter

APS

[Adam]

I maybe wrong on this...

If we use say 98RON fuel all the time but on one trip we can only get 91RON or we get a 'bad' batch of fuel, the ECU can detect this and adjust the AFR and timing etc, so the engine can run safely on this fuel. Right or wrong?

So if I'm right with the above senario does fitting a unichip/exede take this self adjustability away from the ECU since the chip controls these functions? What would happen?

[richdave]

are the figures quoted off the trip computer or manually calculated?