Tune question
Last edited by 04zjimc; Nov 10, 2020 at 10:18 PM.
Last edited by 04zjimc; Nov 10, 2020 at 10:18 PM.
TRY adding to start 20% to the DESIRED AIRFOW table in P/N
Another table is the START UP AIRFLOW CORRECTION table--Try adding again 20%
If you went to far on either you will get a HANGING IDLE rather than dying or an idle flare at start up---
NOT a fan of an SD tune for many reasons --
Data logging with HP or EFILIVE can only tell you if you have outgrown your MAF table which ends at 12000 HZ (about 600 crank HP) on an 04----- on older corvettes 1998 and older the MAF table ended at 11250 HZ which is about 500 crank HP
You have to remember when going to an SD tune there is NO fuel corrections at P/T fueling or altitude changes or air temperature changes-- the fueling is strictly based on the VE table only in your tune--Only racers that have their own tuning software and have the ability to read changes with instruments and make changes to the VE table based on what their instruments are telling them can alter the fueling
If your car has not outgrown the MAF table and you are only a street racer or an occasional track car --you car will become more consistent at a bracket race because the STOCK tuning using the VE table as only a back-up table and uses the MAF as a reference your ECM will self adjust to whatever the altitude changes to and to whatever the air temperature changes to--
I have to say this is a very controversial subject among tuners---This is just my opinion after tuning only GM LS engine for 15 years and have tuned over 3000 vehicles---from stock to bolt ons---from cammed to boosted---I never do an SD tune unless the engine has outgrown the MAF table--Even then I only use what they call an "SEMI OPEN LOOP TUNE"---which still has some adjustability left in the tune--
If your car is mostly a street hot rod I can assume you have drivability issues all the time --cold starts---warm starts---cold weather--warm weather--hot weather----because with an SD tune you need to re tune your fueling almost every few weeks as the altitude--air density and air temperatures change
PS as a retired pro drag racer we used an AD gauge all the time--Average AD is around 97---as the AD raises you need at add fueling to make the same HP as it declines you need to subtract fueling to make the same HP--An SD tune makes no adjustments to AD at all as it is scalded only by RPM and MAP
At WOT MAP is always 14.5 to 14.7 and there is no adjustability there unless you change the VE table every pass as the weather or density changes--Sorry for rambling---












