speed density tuning
02-08-2006, 09:19 AM
#1
Tech Contributor
Thread Starter
speed density tuning
Anyone have info on how to, with the HPtuners, do a speed density tune? I'm looking for the very basics and I know you have to disconnect the MAF but you need the temp sensor inside it still hooked up.
Once that is done, the car is tuned for LTFT's using the VE table and it looks like there is more to it than rpm vs. airflow. Anyone know how that works tuning the VE table? I eventually want the MAF hooked back up.
Once that is done, the car is tuned for LTFT's using the VE table and it looks like there is more to it than rpm vs. airflow. Anyone know how that works tuning the VE table? I eventually want the MAF hooked back up.
02-08-2006, 10:54 AM
#2
Race Director
you can't disconnect the MAF, but you can disable it by changing the overflow error to a very low number.
Basically you have to log LTFT's, then correct the VE table by the same percentage as the LTFT's. I believe HPTuners will automatically correct your VE table (rpm vs MAP) to the correct numbers. After a few itterations, you should get a corrected VE table. At that point, your LTFT's should be very close to zero, and you turn you MAF back on. They you have to log the LTFT's again to see if you MAF is throwing the number off. If it is, you log the actual airflow vs the calculated airflow, and correct you MAF table so that it again brings the LTFT's down to zero.
At this point, you VE tables and your MAF tables are calibrated, together, and correctly, and your car should have crisper throttle response.
It is the same process no matter what software you use, but HPTuners has the advantage of loggin the data and making the corrections automatically.
Basically you have to log LTFT's, then correct the VE table by the same percentage as the LTFT's. I believe HPTuners will automatically correct your VE table (rpm vs MAP) to the correct numbers. After a few itterations, you should get a corrected VE table. At that point, your LTFT's should be very close to zero, and you turn you MAF back on. They you have to log the LTFT's again to see if you MAF is throwing the number off. If it is, you log the actual airflow vs the calculated airflow, and correct you MAF table so that it again brings the LTFT's down to zero.
At this point, you VE tables and your MAF tables are calibrated, together, and correctly, and your car should have crisper throttle response.
It is the same process no matter what software you use, but HPTuners has the advantage of loggin the data and making the corrections automatically.
