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What is a safe minimum a/f for cruising? It's going to take weeks to get it dialed in when I drive to work and back once a week.
HP Tuners VCM Suite
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Pre-ignition is usually the first indicator that you have exceeded a safe limit. AFR is only a measurement of fuel/air where timing and load also play an equally important part in a tune. A engine running a light load can stand a lot more timing and leaner AFR than one thats wot under full load of acceleration. Each engine/vehicle is different. I start out running fat and tune toward a leaner condition. I wpuld suggest on a mostly stock engine to start with a stock tune and adjust the tables you understand to observe their effects on the tune. Keep your changes under 5% and limit the changes until you see a trend that is understandable..
Ok I know this is ancient, but it works great on the 04/05s Rams , took awhile to get into the swing, and dig deep into it .
Spent some where between 100-150 Dyno hours working out some bugs here and there, figuring out what works and what not to do...there's alot of Power that can be found just in fixing the ETC and spark tables ,Airflow TQadjust and the TQ offset from the factory are Horribly wrong and limit the OEM tune not to mention the Airflow TB table , is too large above 1.25 TPSv . , to the extent that there's another 40-60HP below 4k RPMs alone. this is a screen grab from a drive around the block of an 05 Rumble bee, 288k Original mile truck, still has Exhaust manifolds on it on modifications are cat back Exhaust and a K&N air filter in the OEM filter box. I'll send anyone who has HPtuners the HPL log to check it out themselves. The Dragy put the 0-60 run @ 2.95sec , the HPL log has it at min 2.57 , this Bee went 13.93 @ 94 with just a tune(and cat back exhaust) 3.92 gears on Nitto tires and 20 inch OEM Chrome cad wheels.....Pulls like a 392 till 65....then the poor flowing Intake/exhaust manifolds hamper it. we've run this tune in 5 different 05s RC4x2s and each one has dipped in the the high13s, with one getting in to the 13.80s with M&H drag radials.
The difference between HP gauge and HP2 is a lot of math, a lot of trial and error,,,, HP2 Gauge #s are with in 10%(+/-) of what we see on the Dyno which is a New DynoJett 224X
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Tried to Pm it but doesn't have an authorized extension (?) hit me up at rays04gtx at yahoo , or I'm on HPtuners as Rays04gtx and I'll send you the track tune, the VE tables are mostly stock and so is the Injector scaling , I've found with this tune it's better for the "end user" to do their own fueling, because what works at my elevation(300 above sea) is real fat at 2k above sea level.
IT'S A TRACK TUNE...not very daily driver friendly , the Throttle is very "on/off" with 3.92 , with 4.56 gears its more "ON" then off. it goes in to WOT tables and Fueling around 1.6 Pedal V. the knock sensors are off, and the Timing is very flat, limited to 24* no closed loop functions, with average tread wear tires it'll smoke them up to 6000k+ Rpms....which reminds me , all RPM limits are removed in this tune. but start up set point(s) are limited to 1200 RPMS and Idle is set to 720, it has a tendency to surge 50-100 RPMS in P/N till the throttle "adaptive" learns.
Also Table 36040 (FSO table in Torque Management) is set to 967lbs(1311Nm) I've found that after logging a few 1st gear WOT pulls the table needs to be lowered to the PowerTrain Throttle request value at or within 100RPMs of where you want the trans to shift , so this Bee likes to shift at 5200 and the log says (on average) it's requesting 445Ft/lbs(603Nm) around 5200rpms, if the value is too high , it delays shifting 1-2. so in the "as is" state at WOT it'll prolong the shift.
This tune is the base tune that Ric(3xrt) ran in to the high 12's with in a 05 RC4x2 , stock long block, stock cam, headers, stock 545 trans , 2.5 inch true duals dumped behind the cab.....with Cats, I think they were Flowmasters . , gutted interior, LX passenger car Intake manifold, no ac compressor, with a stock 05 Throttle body, 3.92 gears and caltracs, with calvert GM1500 single split leaf's, I think the truck weighed 4250 race weight.
My email is [email protected] you might need to put it in a zip folder before you send it. I no longer have a 545 transmission but I'm still curious as to what you have done to the rest of the tables.
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Here’s some of what went into the basis of this “track tune”
Since 2001 -2023 there have been roughly 8000 days, roughly 300 of those I have had a 03-08 5.7 Hemi on either my Dyno or my long-term employer’s dyno, averaging 6 hours per session….1800 hours. In those hours I’ve found that the 03-08 5.7 Long block is capable of 420-465hp. The OEM head flows average of 250cfm, rule of thumb is power potential for most non- race fuels is 2.44hp PerCFM which = 1.77 Hp/Ci (610 for 345Ci) …. Granted all AREAs of the engine must be optimized to achieve this, and the OEM ECU system is FAR from optimized, we’ve made 460Hp with old school 340 SBM’s with roughly the same cam specs and less CFM. Our factory stock 345 Drag pak car is making 495hp with a .490 lift cam and 265CFM @ .500 lift.
When we did the Pre-production endurance testing, we were seeing 365-370 with the Engine management system DCX provided….basically a non-torque management ,no AFR limit version of the ECU and it was limited to 20* of spark all in by 3k RPMs
We’ve all heard it before Hemi’s Love Boost…..What is Boost, it’s airflow and Compression….Hemi’s LOVE airflow, and the Nm/Tq/air-Tq Offset table is not your friend, along with Throttle Air flow and Torque Monitoring Loss tables, long story short, if the ETC request is out side the OEM values the ECU limits the power potential.
Keep in mind that the OEM ETC is only requesting 20-35% of the engine power up to roughly 3000k in “commuter” driving situations…. Once you set it up to request 65-80% in that same rpm range it’s like adding 100hp under 3k rpms.
Knock Sensors in the 03-08s are too sensitive and 9 out of 10 times it pulls spark is due to transmission shift scheduling, the trans doesn’t down shift adding duty load, so ECU pulls 1-5* out when it should downshift to ease the current engine load.
OEM Spark tables, a lot of what you see in the 50KPA and below Map area of the PT spark table is strictly for emissions, it’s to help burn off unburnt fuel when you let off the gas pedal, but it casues Knock reading in adjoining cylinder.
I could write a whole chapter on this….but I digress.
Since 2001 -2023 there have been roughly 8000 days, roughly 300 of those I have had a 03-08 5.7 Hemi on either my Dyno or my long-term employer’s dyno, averaging 6 hours per session….1800 hours. In those hours I’ve found that the 03-08 5.7 Long block is capable of 420-465hp. The OEM head flows average of 250cfm, rule of thumb is power potential for most non- race fuels is 2.44hp PerCFM which = 1.77 Hp/Ci (610 for 345Ci) …. Granted all AREAs of the engine must be optimized to achieve this, and the OEM ECU system is FAR from optimized, we’ve made 460Hp with old school 340 SBM’s with roughly the same cam specs and less CFM. Our factory stock 345 Drag pak car is making 495hp with a .490 lift cam and 265CFM @ .500 lift.
When we did the Pre-production endurance testing, we were seeing 365-370 with the Engine management system DCX provided….basically a non-torque management ,no AFR limit version of the ECU and it was limited to 20* of spark all in by 3k RPMs
We’ve all heard it before Hemi’s Love Boost…..What is Boost, it’s airflow and Compression….Hemi’s LOVE airflow, and the Nm/Tq/air-Tq Offset table is not your friend, along with Throttle Air flow and Torque Monitoring Loss tables, long story short, if the ETC request is out side the OEM values the ECU limits the power potential.
Keep in mind that the OEM ETC is only requesting 20-35% of the engine power up to roughly 3000k in “commuter” driving situations…. Once you set it up to request 65-80% in that same rpm range it’s like adding 100hp under 3k rpms.
Knock Sensors in the 03-08s are too sensitive and 9 out of 10 times it pulls spark is due to transmission shift scheduling, the trans doesn’t down shift adding duty load, so ECU pulls 1-5* out when it should downshift to ease the current engine load.
OEM Spark tables, a lot of what you see in the 50KPA and below Map area of the PT spark table is strictly for emissions, it’s to help burn off unburnt fuel when you let off the gas pedal, but it casues Knock reading in adjoining cylinder.
I could write a whole chapter on this….but I digress.
Great explanation. I love reading this stuff, knowledge is power. And you are empowering me to create a better tune for my truck...... It will mostly be a daily driver. And I probably will only run about 10 pounds of boost. I have had it as high as 15 but it gets a little squirrely for the street.
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