dyno tuning question
dyno tuning question After my heads and cam install oddly enough, my car runs really good. I am about to go to the dyno to see where my air/fuel is at WOT. My question is what parameters (in HPTuners), do I adjust for air/fuel with the MAF connected? Can I do this or do I need to tune in SD mode?
Originally Posted by 00Z28SS
After my heads and cam install oddly enough, my car runs really good. I am about to go to the dyno to see where my air/fuel is at WOT. My question is what parameters (in HPTuners), do I adjust for air/fuel with the MAF connected? Can I do this or do I need to tune in SD mode?
You don't properly tune by changing the PE table. That changes the "commanded air fuel ratio"
If your not commanding and getting what your commanding, something in the control system is being lied to.
You need to alter the airflow or fueling values based on what could be incorrect. Typically it is airflow that needs the adjustments, either through the maf, or VE tables depending on your tuning method
Ryan
If your not commanding and getting what your commanding, something in the control system is being lied to.
You need to alter the airflow or fueling values based on what could be incorrect. Typically it is airflow that needs the adjustments, either through the maf, or VE tables depending on your tuning method
Ryan
Most turners don't want to take the time to properly tune the VE Table so they just play with the PE Table like Birdonnos said to adjust the A/F at WOT. If the VE Table was properly tuned and you want a 13.0 A/F ratio then the PE table would be 1.13 all the way across. To properly tune the VE Table you need to be in SD.
Originally Posted by slow
You don't properly tune by changing the PE table. That changes the "commanded air fuel ratio"
If your not commanding and getting what your commanding, something in the control system is being lied to.
You need to alter the airflow or fueling values based on what could be incorrect. Typically it is airflow that needs the adjustments, either through the maf, or VE tables depending on your tuning method
Ryan
If your not commanding and getting what your commanding, something in the control system is being lied to.
You need to alter the airflow or fueling values based on what could be incorrect. Typically it is airflow that needs the adjustments, either through the maf, or VE tables depending on your tuning method
Ryan
Your right most tuners don't take the time to tune the airflow side of things correct, and just do a blanket change with the PE table.
Personally, I would be changing the maf, to achieve what your commanding at the higher rpms, and adapt the VE table for the lower portion under 4K, but correcting the full VE table is probaly the correct method, as well, but that is a lot more work for little benefit imho.
Ryan
Personally, I would be changing the maf, to achieve what your commanding at the higher rpms, and adapt the VE table for the lower portion under 4K, but correcting the full VE table is probaly the correct method, as well, but that is a lot more work for little benefit imho.
Ryan
Alright, here is my situation. With my MAF connected all of my LTFT's are -5 to +4, which is good enough for me considering all of the work. I do not have a wideband so I have not properly adjusted WOT tuning, I believe I am running rich judging by the 920+ mV readings at WOT. I will be using the dyno's wideband which will give me printout reading; from this printout the only thing I need to adjust is the PE table?
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Originally Posted by slow
Your right most tuners don't take the time to tune the airflow side of things correct, and just do a blanket change with the PE table.
very true....I am correcting a lot of tunes in KC because of a "tuner" that charged a bunch of money for dyno tuning...and only really did a PE change and didnt even touch anything else
Originally Posted by slow
Personally, I would be changing the maf, to achieve what your commanding at the higher rpms, and adapt the VE table for the lower portion under 4K, but correcting the full VE table is probaly the correct method, as well, but that is a lot more work for little benefit imho.
Ryan
Ryan
your car does not run on MAF alone...especially in low load low rpm low throttle situations. It is a blend between VE and MAF...so it IS important that you get your VE correct as well...
One of the best ways(well proven)..
USE A WIDEBAND AT ALL TIMES
correct the VE table as you drive it(and with DFCO off)...(meaning do it with PE on)
hit all rpms and all load ranges
get your Actual AFR to match your Commanded AFR(use AFR Error %)
next do the MAF teh same way, Trying to hit as many MAF HZ as possible
again using AFR error % to get it correct
then you can try to get your stock O2's to line up with your tune if you want to try...(I think I have found a method that works...still testing to make sure Its not a fluke... and working on getting something else inplimented in HP Tuners 2.0- I am a tester
) 
