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It's been since 2009 and now I'm back! Just got a new set of Texas Speed and Performance PRC 247 heads for my 408 and now I need help with tuning. Solid Roller Cam 265/272. CFM changed from 330 to 360 so I'm obviously lean. Car starts, idles, & runs but dies while driving... I have HP Tuners but I will share I'm new to the tuning game..Any help or suggestions will be greatly appreciated.
Yep, I understand but hey isn't that the fun of it... It is time for me to learn the programming side of things. Previous - 2 tunes, 1 for street where I believe the WOT timing was set at 26 degrees while the Nitrous Oxide tune WOT set at 16 degrees - at least that is what I understood back when I had the previous heads..
^^^^^^^^Do this; it's why I asked what you had. ^^^^^^^
Ok, being new to the tuning and attempting to post I cannot seem to copy and paste the file in this thread. Where do I need to go to post it?
I have a 408 (LQ9) TSP 247 heads 360 CFM @ .750 inch lift. LSX90 Intake, Nick Williams Throttle body.. Callies Crank, Callies Compstar Rods.. Bullet Custom Ground Solid Roller Cam 265/272 @ .50 inch lift 108 to 110 Lobe center. Kooks 1 7/8 headers, no cats - Manual 6 speed. Moser 12 bolt Spool 4:10 gears. Crane Roller Rockers and Lunati solid roller lifters. Direct Port N20 with Octane On-Demand. 2 fuel tanks... 6 point cage. About all I can remember at the moment.
Yes, O2 Wide band sensor in the car - did not have it plugged into HP tuners today. First day back after a very, very long time of being down...
You have what sounds like a fun combo. When you figure out how to post data logs I am sure you will receive a lot of feedback. If you don't figure out how to post logs, we will just assume you are a useless dumbass.
Ok, and here I have posted the table for the engine tune with previous heads flowing 330 at .695 lift now flow 360 .750 lift. Same cam, intake, headers, the only change are the heads flowing 30 CFM per chamber more. Any suggestions? And definitely asking for help. Thanks,
That is your main spark table, which may not need much work, depending on how close it was to ideal with your previous combo. The VE table is the one which will need the bulk of the work as far as power and drivability. Since you said it starts and idles without problem, the bulk of your difficult work is behind you. Once you get your histograms set up to record AFR error from your wideband, HPT has a convenient feature for copy/pasting percentages of error into VE percentages multipliers. Most people typically paste half the error at a time, in order to avoid overcorrections. Also, adjoining cells in the table affect each other, so hand smoothing is sometimes needed. Make sure to filter your histograms so that it takes several hits to update each cell in order to limit erroneous data. Be certain that you are looking at the average histogram data instead of min or max per cell before copy/pasting anything. An errant mouse click or fat fingered touchscreen can really screw up your process.
That is your main spark table, which may not need much work, depending on how close it was to ideal with your previous combo. The VE table is the one which will need the bulk of the work as far as power and drivability. Since you said it starts and idles without problem, the bulk of your difficult work is behind you. Once you get your histograms set up to record AFR error from your wideband, HPT has a convenient feature for copy/pasting percentages of error into VE percentages multipliers. Most people typically paste half the error at a time, in order to avoid overcorrections. Also, adjoining cells in the table affect each other, so hand smoothing is sometimes needed. Make sure to filter your histograms so that it takes several hits to update each cell in order to limit erroneous data. Be certain that you are looking at the average histogram data instead of min or max per cell before copy/pasting anything. An errant mouse click or fat fingered touchscreen can really screw up your process.
Thanks, learning here and it's definitely a process. Next, plan to hook up the wide band and collect data. AFR numbers according to my meter look pretty good (12.5 to 13.7). Need some drive time to work out the kinks (which is a little risky, guess I will pull the NOS bottle out) This is when I need a dyno at my house. Thanks again.
As numerous drag builds with old school distributors have proven, he could lock out that spark table to a single number and still be drivable. He needs to get the fueling close before worrying about the spark too much (as long as it doesn't knock).
Finally got a log file! It's been hell to say the least and I'm sure there will be a lot to laugh about. Any help or suggestions? I am now getting a P0200 Injector Open loop. Checking into connections and plan to scope injectors, also know of a potential work around. But hey, I'm getting close and want to get this on the road in 2 weeks or less.
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I'm back and need help with Tune 
