Calc.VET, Desired Airflow, Idle RPM, A/C and questions related to these within...

1. Should I do Calc.VET or Desired Airflow first in tuning?

2. Should I do Calc.VET with A/C on or off (other than WOT of course)?

3. Should I do Desired Airflow with A/C on or off? Or do you just let the A/C tables in the Idle section take care of it, and just do desired airflow without A/C?

4. Lastly assuming I have gotten my idle down perfect at say 725 rpms (in my 6.0 cam, heads, full bolt on engine), what would be the most important things in the tune to work on to be able to drop the rpms at idle to 600-650?/Or does dropping the rpms at idle even result in any benefits such as mpg, etc.?

5. With Calc.VET, I have read that you can choose to just use the WB02 input and not the LTFTs. But if I have MAF at 400 (Open Loop), and LTFTs Disabled, Do I still need to log LTFT1 and LTFT2 to show 0 for the LTFTBEN calculation?/Or can I not log the LTFTs and leave off the LTFTBEN Calculation and it still work correctly?

Thank you

Do Calc.VET first with AC off.


Then do RAFIG/desired airflow with AC off, and then with AC on.


Idle rpm is dependent on the cam specs (overlap).


Yes, disable CL/LTFT/STFT/SOL and then use the pid WO2BEN instead of SELBEN... you do not need to log LTFT or LTFTBEN as long as CL and trims are disabled.

i.e. in the Calc.VET procedure, for the MAF map use CALC.WO2BEN as the pid on the Data tab, and in the file calc_pids.txt use CALC.WO2BEN in place of CALC.SELBEN in CLC-00-305.

So I am going to put my Desired Airflow back to stock 6.0 levels before doing Calc.VET.

1. Do I need to put any other idle tables back to stock before doing Calc.VET? Because I just finally got enough changed to where it will finally drive/idle well without stalling.

2. How do I disable STFT and SOL?
I disabled STIT, but not sure where in 2002 OS STFT and SOL are.

3. My cam is a 222/224 .604/.604 on 112 LSA. It idles at 725 when up to operating temp without issue anymore. Is there any benefits to getting it to idle lower while stable?

Quote:

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Originally Posted by joecar

Do Calc.VET first with AC off.


Then do RAFIG/desired airflow with AC off, and then with AC on.


Idle rpm is dependent on the cam specs (overlap).


Yes, disable CL/LTFT/STFT/SOL and then use the pid WO2BEN instead of SELBEN... you do not need to log LTFT or LTFTBEN as long as CL and trims are disabled.

i.e. in the Calc.VET procedure, for the MAF map use CALC.WO2BEN as the pid on the Data tab, and in the file calc_pids.txt use CALC.WO2BEN in place of CALC.SELBEN in CLC-00-305.

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You won't mess anything up doing calc.vet or any other log by using the correct (and by correct I mean what keeps your car running after a full flash, not the incorrect values entered by GM) desired airflow/ac tables/idle rpm value.

You may have to massage the airflow tables after you do calc.vet, depending on how large your corrections are.

All the auto/calc.XXX tuning procedures are looking at a certain sensor to calculate air mass, and correcting any error from that calculation from the data the o2 sensors provide.

The tables you asked about all deal with how much to open the IAC/throttle to maintain desired idle conditions. They are not effecting the calculations concerning the amount of air entering cylinder at a given MAF freq or manifold pressure, (which is specifically what calc.VET will correct and calculate).

I have modified the desired airflow and idle speeds considerably and perform auto.VE with that tune and I am very happy with my results.

****However**** if you wish to collect any data around 400 rpms I do not know how to do that without reducing the desired airflow at idle values.

You can just proceed from where you are now (first make sure there are no sharp steps/kinks in the VE and MAF tables).


Make sure your your IFR table is correct (note: un-referenced FPR -> IFR is sloped; MAP-referenced FPR -> IFR is flat).


CL: B3801 disable.
LTFT: B4205 disable by setting temperature to max.
STFT: if B4206 exists, disable.
SOL: if COS, then in B3647/B3649 set stoich cells to non-stoich (if stoich EQ 1.00, set to EQ 1.01 or EQ 0.99).