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View Full Version : Best tables to adjust for tuning the following



Jason S.
May 25th, 2005, 04:12 AM
It seems there are several ways to "skin the cat", but I am having a hard time figuring out the best tables to use to tune the following on a Maf car.

Idle afr
light load driving afr

It seems it can be done with the injector flow rate, but is this a band aid way of doing this?

Does the main v.e. have ANY affect while in MAF mode?

When in Open loop mode, is the fuel only read out of the EQ ratio when in open loop?

Sorry if these questions seem elementry, but I am use to tuning complete stand alone computers where things are a bit more obvious.

Thanks for any input.

Jason.

QUICKSILVER2002
May 25th, 2005, 04:31 AM
Idle afr
VE,MAF, IFR, Injector offset, Base Spark - for closed loop
VE,MAF, EQ in Open Loop, IFR, Injector offset, Base Spark - for open loop
Idle Airflow - to control how open the TB is (but idle tims take over to maintain RPM)



light load driving afr
pretty much the same as idle


It seems it can be done with the injector flow rate, but is this a band aid way of doing this?
Depends on how you look at it. IFR is not very targeted (just MAP - not RPM...). I don't like to mess with it.


Does the main v.e. have ANY affect while in MAF mode?
Yes, but mainly during throttle transitions (transient states). It is pretty much out of the picture during steady states. VE is also totally out of the picture after 4k RPMs.


When in Open loop mode, is the fuel only read out of the EQ ratio when in open loop?
That is where the target is determined.


Sorry if these questions seem elementry, but I am use to tuning complete stand alone computers where things are a bit more obvious.
Yea, these are much more sophisticated in reality.



I think the best approach is to leave IFR alone. Put the car in SD mode (run without the MAF). And get the VE table dialed in. Then turn the maf back on and make the little tweaks to the MAF tables to keep the maf from screwing things up.

Jason S.
May 25th, 2005, 05:37 AM
Thanks for the quick response. That helps a bunch!

Jason.

Jason S.
May 25th, 2005, 05:56 AM
Is running in SD as simple as unlplugging the maf meter? Or do I need to do anything else?


Jason.

QUICKSILVER2002
May 25th, 2005, 11:51 AM
Is running in SD as simple as unlplugging the maf meter? Or do I need to do anything else?
Jason.

You won't want to unplug it if it is a newer car with the iat sensor integrated into it.

You can set the maf fail frequency to 0 to force SD without unpluging it (but it may require you to start the car twice before it fails the MAF).

Somone said you could turn it off with bi-directional controls, but you would have to go find that thread and try it.

Jason S.
May 30th, 2005, 04:01 AM
That's it, just set that to 0? Easy enough...Thanks

Also, what kind of change is necessary to the ETC table {c6101}? If any?

Thanks again

Jason.

jfpilla
May 30th, 2005, 11:26 AM
That's it, just set that to 0? Easy enough...Thanks

Also, what kind of change is necessary to the ETC table {c6101}? If any?

Thanks again

Jason.

If you want to be sure the MAF has failed, select GM.MAF lbs as a PID. It will only show 0's when the MAF has failed. This is true for late model C5's. F-bodies may want to chime in.

Jason S.
May 30th, 2005, 12:21 PM
Mine is a C5...thanks for the input. Any tips on the ETC map {C6101}?

Thanks

Jason.

jfpilla
May 30th, 2005, 12:52 PM
Mine is a C5...thanks for the input. Any tips on the ETC map {C6101}?

Thanks

Jason.

If you have a stock TB it's not likely you will set the 1514 code. I have a 90mm setup and it initially set the code. After tuning I went back and put the stock file in and have not had a code set in a year. When I did set the code, I raised the table 10% and it went away. I haven't seen much written about this. I guess it's because it doesn't happen often and it's easy to correct.

I think the best approach is to leave IFR alone. Put the car in SD mode (run without the MAF). And get the VE table dialed in. Then turn the maf back on and make the little tweaks to the MAF tables to keep the maf from screwing things up.
I'm with QS2002. IFR's should be set to whatever injectors you have, if you want WOT AFR to be what you set.

Jason S.
May 30th, 2005, 01:29 PM
O.K. great...thanks for the feedback. Does it hurt to bump it up anyway? It seems it is just a limit, so if you move it out of the way, does it have any negative affects?

Thanks again.

Jason.

jfpilla
May 30th, 2005, 01:43 PM
O.K. great...thanks for the feedback. Does it hurt to bump it up anyway? It seems it is just a limit, so if you move it out of the way, does it have any negative affects?

Thanks again.

Jason.

I don't think so. I'm not big on changing things that don't need to be, though.