I have talked to two different tuners and gotten two different and conflicting scenarios for tuning my dad's 03 Z with an STS TT kit on it. One guy who has tuned for me before and done great work told me that to tune the car to 600hp it would need a SD tune as the maf is only good to about 500hp. another guy who has a good reputation told me that the maf tune would work on our setup and he claimed he has gotten several 600ph cars with our setup. I have three questions stemming from all of this, firstly I have been told a very wide range of numbers to expect from this system from 500-700hp, this is an otherwise stock Z06 that is not worn out with an expected 7lb of boost, what have others gotten out of this setup? Secondly can we get all of the available HP with a MAF tune or will we have to switch the car over to MAP? And lastly if needed how bad would the SD tune hurt the car's drivability and reliability?

thanks in advance for setting me straight.
Bill

 

The MAF table is limited to a max airflow amount. I've gotten around this limitation on my blown chevy truck by scaling the air and fuel flow values in the tune.

 

At what boost level did you max out your stock MAF?

 

Around 8-10 psi in a cammed 5.3

 

Many variables involved in whether a MAF system will be sufficient or not besides just amount of boost or aiflow
Early MAF's would max out at 11250 HZ Correct--- about 500 HP
YOUR 03 Z06 has the newer style that maxes out at 12000 HZ--So it is capable of about just under 600 HP
A lot of it depends on your air intake system's flow path and the placement of the MAF sensor----Depending on that --it can alter the MAF 's reading to read low or high--mostly low
As an example on my C7 with the stock airbox my max MAF reading was 9400 HZ
However after adding an AFE cold air intake and re-positioning the MAF location it now reads a max of only 8850 HZ---So it actually reads lower on the table--A complete rescaling of the MAF table was needed to correct
YES with a SD tune there is no fuel corrections at P/T when changing extreme altitudes
( usually over 4000') drivability can suffer--
If it were my car----I would 1st tune it WITH the MAF--Only then after data logging you can see exactly where on the HZ table you end up---If you end up OVER 12000 HZ then it would be no big deal to THEN convert it to a SD tune--Your tuner my charge something for another tune but I would always prefer the MAF tune to protect drivability
and a constant need for monitoring fuel
Another option that I've used before is called a "semi open loop tune" or an OL tune
This still uses the MAF
An SD tune uses the "VE" table solely for fueling
A stock closed/open loop tune uses the front 02's and MAF for fueling-and the VE table only as a reference during " rapid changes in airflow "
A open loop tune uses the MAF only no 02's and the open loop table for fueling and the VE table again only as a reference during RCIA