SD tunes???
I've posted a lot about it before (if you search posts from my name with "speed density" you will find them).
Short of that is...I don't feel there are any drawbacks at all. I've had excellent results tuning speed density on everything from mild to wild. All of the naysayers usually don't understand how to properly tune/calibrate it.
Short of that is...I don't feel there are any drawbacks at all. I've had excellent results tuning speed density on everything from mild to wild. All of the naysayers usually don't understand how to properly tune/calibrate it.
TECH Senior Member
Joined: Apr 2002
Posts: 6,080
Likes: 17
From: So.Cal.
No drawbacks...
You may have to edit the transmission failsafe/max pressure tables to ignore a MAF DTC or two.
Think about this:
with a CLMAF tune, PCM reads airflow 12" to 20" upstream of combustion chambers, and reads NBO2's 20" to 40" downstream of the chambers... i.e. it is calculating airmass/fueling using future/past values...
with an OLSD tune, the PCM calculates airmass/fueling based on instantaneous table lookups (i.e. you have to first fine tune the tables using a wideband)... so even tho CLMAF and OLSD make the same HP and TQ numbers, OLSD gives quicker throttle response.
Also note that the VE table's units are g*K/kPa... i.e. it is normalized/corrected for temperature and pressure.
Both ways are good and have their own "features".
My $0.02.
You may have to edit the transmission failsafe/max pressure tables to ignore a MAF DTC or two.
Think about this:
with a CLMAF tune, PCM reads airflow 12" to 20" upstream of combustion chambers, and reads NBO2's 20" to 40" downstream of the chambers... i.e. it is calculating airmass/fueling using future/past values...
with an OLSD tune, the PCM calculates airmass/fueling based on instantaneous table lookups (i.e. you have to first fine tune the tables using a wideband)... so even tho CLMAF and OLSD make the same HP and TQ numbers, OLSD gives quicker throttle response.
Also note that the VE table's units are g*K/kPa... i.e. it is normalized/corrected for temperature and pressure.
Both ways are good and have their own "features".
My $0.02.
