translator+ / extender questions

[Warped]

According to the DS data this chip seems to command a WOT AF ratio of 12.6 where most other chips I've seen shoot for 11.6. Is this correct and if so, why?

Also, it appears that when you add fuel via the translator the maf numbers go up. Is that how they add fuel, tricking the ecm by telling it there is more air flow than really exists?

Thanks.

 

[BJM]

The difference with the Extender chip is the translator needed to use it. The Extender with the translator can measure accurate MAF readings beyond 254-255, (up to 512 or 768 if needed). Since it has an accurate MAF value, it can command an appropriate A/F ratio.

Every conventional chip has to guess at the appropriate amount of fuel since the air flow value pegs at 254-255. Once the MAF pegs the tuner knows more air is going into the engine but the MAF cannot tell you the amount. The ECM keep plugging 254-255 into the pulsewidth calculation and gets the wrong number (too lean). So by decreasing the A/F ratio continually while in Power enirchment mode the tuner has made their best guess as to how fast the actual airflow is rising and has commanded an unbelievably rich mixture for the ECM to arrive at the actual correct number.

As far as tricking the ECM with air flow, there is no right answer. The MAF is a low accuracy device anyway. If the flow doubles it will tell you pretty reasonably that 20g/s became 40 g/s, but was the original 20 actually 15 or 25, the MAF is not really accurate enough to know.

 

[Dean]

Originally posted by Warped
Also, it appears that when you add fuel via the translator the maf numbers go up. Is that how they add fuel, tricking the ecm by telling it there is more air flow than really exists?

It appears so, though I haven't actually confirmed that with Bob.