How to tune WOT

[Xtnct00WS6]

Could someone explain in as much detail as you can, how to tune WOT? If you could include target ARF at peak torque and hp, that'd be great.

Are you supposed to be in Speed Density when you tune WOT?

Could you explain how the main VE table works with the PE table?

Thanks!

[Happy Jim]

Here's a good place to start...

http://forum.efilive.com/showthread.php?t=6328

Rgds

Jim

[Xtnct00WS6]

Thanks, I'm more interested in the procedure than anything.

[joecar]

The PCM uses the VE table and/or MAF to calculate airmass;

In open loop, the PCM then looks up the AFR in B3605/B3647 CFOL and B3618 PE, and selects the richer of those;

In closed loop, the PCM uses stoichiometric AFR and uses LTFT to trim to this AFR;

at WOT, PCM goes into open loop, but if the LTFT was previously positive, my understanding is that the PCM then adds the LTFT also on top of the richer of B3606/B3647/B3618.

[ringram]

Thats my understanding too. Which is why a good ve table is essential. It removes the LTFT error and extra fuel dumped in.

[Doc]

Could someone explain in as much detail as you can, how to tune WOT?

Plenty of detail on this site and others.


If you could include target ARF at peak torque and hp, that'd be great.

Depends on the application, N/A (12.8-13.1), N20 (shot size?) see attached Beer spreadsheet for more info...
http://www.ls1tech.com/forums/showthread.php?t=841248

Peak torque can be measured in many ways. Dyno, track, Gtech RR pro, and or knock sensors are the basic accepted methods, there are more exotic ones tho.
These basic methods are simply trying to measure peak cylinder pressure in an economical fashion. Start below and in small increments and advance. As with the fuel, timing is going to vary based on application. Searching for your app on this and many other forums will yield basic guidelines.


Are you supposed to be in Speed Density when you tune WOT?

If you follow the AutoVE tutorial / basic principles you should put the car in OLSD first then do the MAF if you choose to run it.


Could you explain how the main VE table works with the PE table?

As has been eloquently explained before in this thread, the VE table is merely a reflection/prediction of Airmass as detected by the MAP sensor. The PE table is just a commanded A/F value. You have to have the airflow right before you can accurately command fuel.

Thanks![/quote]

No problem, understanding the basic operation will make the tuning "process" easier to get your arms around.

[stigmundfreud]

Thats my understanding too. Which is why a good ve table is essential. It removes the LTFT error and extra fuel dumped in.

What if you were to disable LTFT and just run STFT for CL. I know CO3 supports this but does the standard OS accept it?

[notgetleft]

What if you were to disable LTFT and just run STFT for CL. I know CO3 supports this but does the standard OS accept it?

I've been doing that for a few months now in an 04 GTO and it works fine. LTFTs seem to be pretty useless once the tune is close.