BOSS 3.0
Dec 19 2007, 04:55pm
I finally got to hit the dyno yesterday and do a baseline on the Explorer (1998, 4.0L SOHC, 5R55E, 2WD, 3.73LS), 87 tune and, some tweaking time. Over $250 in dyno charges (ouch), but later runs will be far cheaper since there won't be any data logging going on at the same time. There were dozens of questions as to why certain things are done certain ways, and why it's a good idea not to follow some other groups/ideas.
So, who needs a dyno run?:
Anyone that has modified their MAF, modified their vehicle so much that the PCM has to "re-learn" the idle if cleared, installed nitrous or forced induction, or wants to have hard evidence of the "fruits of their labor".
What vehicles can be run?:
Depends on the site doing the testing, the big issue being 4wd or AWD. These require a 4 wheel dyno and that is more expensive/harder to find. There should be NO LEAKS, NO SMOKE and NO MECHANICAL PROBLEMS. You should have a "fresh" tune up, with properly gapped plugs, good wires, good cats, good injectors, NO PINGING, good tires (plenty of tread, properly inflated), good O2 sensors (especially Pre-Cat), a working e-brake and topped off fluids. If you are prone to pinging, overheating or stalling, this is not for you. Time is money and some places charge heavy fines for spilled fluids. If you have any of these issues, you are really wasting your time and money. I recommend doing the tune up and MAF cleaning the week before if you want to compare a "Learned Stock" run, flashing the unit back to stock (for a limiters run) instantly gives you a "no-learning" profile since the KAM (Keep Alive Memory) is wiped clean on a reflash. A clean (or cleaned/reoiled) air filter is a great idea too.
What to bring:
Laptop, spare laptop battery (or DC-DC convertor!), LiveLink 4.17 (or better), USB device cable, digital camera, soft drink(s), pen/pencil, notebook, tuning manuals/reference material, common hand tools, MAF cleaner, rags and a well thoughtout game plan.
What to watch for:
The ABS light on most vehicles will come on since the rear wheels are turning and not the front, this is normal, and the light will go out a few minutes after leaving the dyno.
Scheduling:
Make plans well in advance, I actually scheduled for last Saturday, two weeks prior. Just so happens we got 4" of snow last Saturday, following massive flooding the week before. So, Friday I called to verify and then again on Saturday. Showing up early was well worthwhile as I got to see a twin-turbo Z05 Corvette... sweet.
Many places offer a discount for "groups", but you will get NO tweaking time and they will do 3 (or so) quick pulls. You may have time to swap tunes, but not tweak/adjust anything except the WOT fuel or timing via "User Controls" on your SCT device.
I had the SCT X3 PowerFlash tuner loaded with a modified stock profile (no limiters, but not "tuned"), an 87 profile and a 93. This allows for a quick transfer of files and a minimum amount of wasted time while strapped to the roller - that gets costly! Now, the vast majority of my dyno experience has been lowered Rangers, Explorers and Focii with "Z" series tires, so the standard procedure is to SLOWLY row the stick through the first 4 gears (all were 5 speed O/D), then stab the throttle at the lowest RPM you can get without lugging the engine. On an auto, I have a special profile that locks the TC and trans in 4th gear, deselect the O/D, and set the IAC up a bit to keep it from stalling on the dyno. Rev the engine to just over a grand in neutral and drop the selector in to "D". With the extra IAC air and the RPM's, it is enough to get the roller moving (preventing an embarrassing stall!) and you're off in high gear with minimal losses and no silly 4,800 RPM "flare" from the TC.
But, this is the first time I'm testing a lifted truck with 32" mudders. These are "S" rated tires which were recently balanced. This puts them at approximately 112mph, and the Focus (with 3.8:1 gears and 24" tires) hit 119mph, easily. We know most Ford trucks have a speed limiter at 87-95 mph (with factory tires), and that should be over 100mph with the 32's. So, since I'm doing a dyno article for another forum, I figured I'd go Barney-style; deselect O/D, drop it in "D" and stab the throttle (later referred to as "D-Stab" runs).
Here is the ugliness:
http://www.rogueperformance.com/pix/Explorer/Dyno_87_Oct_8-12-07_Baseline.jpg
What do we get out of this mess? Well, we can see that first gear is completely useless, the time is too short to glean any useable data. Second gear is nice, starts reasonably low and gets well over the magical 5252 (TQ/HP crossover) and shows until HP tails off. Third gear is a little weak, it starts late (just before the 5252 convergence, but after peak torque) and ends normally. Fourth is by far the sweetest gear for real numbers - unless you have a stock limiters. The speed limiter, in this instance, hit at 105mph, and at 4,860RPM's - much too soon. The reason for the 105mph speed limit? Start with 1 divide it by the 28” tire, times a 32” tire = 1.14 x the 92mph limit = 104.88mph - coincidence? Not! Notice the rapid drop in HP/TQ numbers? They correspond with the rapid increase in the AFR (18:1 at botton of graph) since the PCM pulls injector dwell time to limit speed and rpm’s. Major problems for nitrous and forced induction folks - this would be blown head gaskets for sure.
The other obvious signs are the radical spikes (increase) in HP/TQ at each shift. These are not only unsightly, but they fool the dyno computer in to thinking they are the peak HP/TQ numbers. The readouts stated that my peak numbers were 200.1HP and 221.23TQ, completely wrong. The true numbers were 181HP and 188TQ. I plugged these in to the “Rogue Dyno” and got 181HP and 189TQ - Hmmmmmm…..
Remember, these are "unlearned" bone stock PCM numbers, the torque numbers are low, but I attribute this to the lack of learning.
http://www.rogueperformance.com/pix/Explorer/Dyno_87_Rogue_Baseline.jpg
Now, compare these first two charts:
"Smoothing":
Notice on the first graph that "smoothing" is set to 5, this is the highest setting. Smoothing makes the chart look, well, smoother. It removes some of the jagged edges and rough spots in the chart. While this does look good, it is basically a lie. Now, look at the "Rogue Dyno" and you will see the staircase-like look of the run. This is because there is no smoothing, it is plotting the data as listed. Smoothing is adjustable in most dyno viewers (like WinPEP 7). To analyze the data - set smoothing to 1, to post on the web, set it higher.
What's the verdict, what did we learn?
-Safety first: 2nd gear only runs for any non-speed tires. I still prefer 4th gear for better data, but 2nd is perfect for mudders.
-Rev/speed limiters are pretty evil, annoying and unsightly.
-The Excell dyno works dead-on if the factory torque limits are untouched.
Now, for contrast, here is what most people expect to see:
http://www.rogueperformance.com/pix/04+Ranger/JLM.jpg
This is a bone stock 3.0L Ranger, Auto with the TC locked using that 4th gear trick. Sweet huh? No guessing, the computer posts everything you want/need. But, there is no way to get this with an auto trans (and "S" rated tires!). So, how did that first run come about if there are rev-limiters speed limiters and other evils in the stock PCM? Easy, you pull up a bone stock profile and change only the IAC, limiters, TC lock and trans lock functions. No timing tweaks or fuel tricks. While it is tough to get in there and resist the urge of changing everything, this way ensures a true before/after scenario. This means much more work on your tuners part, but one look at the results and I'm sure youll agree, it is worth the effort.
So, what to do? Put the selector in "2" and go. No fuss, no muss, but there may be some TC flare...
The before and afters here are a showing the added fun of a 75mm MAF and 14" K&N cone filter.
Notice, run one (-002 actually) is typical, late open loop. The AFR stays at 14.63:1 until 4,100RPM's when the TPS is well past 663 and the open loop timer has run out. Then it drops to 12.5:1. Run two (actually #14 of 15 runs that day) has WOT instantly rewarded with 13:1 for the duration of the run. While 11rwhp and 12lb/ft of torque may not seem like much, this has a stock exhaust and is running on 87 pump gas with no mods besides the MAF and filter.
http://rogueperformance.com/pix/Explorer/87_Oct_8-12-07_BaseTune_1-2.jpg
This is run 1 (w/ factory limits) and run 2 (no limits). Notice the 4th gear run is much longer, and goes 22mph faster than the tire ratings (135MPH)? Now, this is with oversized tires, and it will be regeared for 4.30's with the 33's, but the top speed will still be well over the limts of the tire's speed rating ("S" in this case).
This should MORE than settle the debate of 2nd vs 4th (or 1:1) gear runs for those of us with oversized tires.
If you have "Z" rated radials and want to have the "best" data - go in 4th, or whatever your 1:1 gear is.
http://www.rogueperformance.com/pix/Explorer/Dyno_87_Rogue2_Baseline.JPG
"RogueDyno" appears to be off by 4% with the increased output.
Start at 181HP, end at 188hp, increase = 3.8%, so this might be the problem.
Ladies and Gentlemen, it is my distinct privilege to introduce to you, the worlds ugliest Dyno chart!
http://www.rogueperformance.com/pix/Explorer/87_Oct_AFRTune_3.jpg
This was a 6 month old tune that was run on the street DAILY with no issues whatsoever. Put it on the dyno and what do you get? A bowl of spaghetti, complete with wheelspin, rev-limiter hits, 20+:1 AFR's and all sorts of foolishness.
Notice: The 5252 convergence is AFTER 120MPH, so this run would never show peak HP unless you went WELL above the the 112MPH tire limit. Where would we be at MAX HP? 142MPH. ...rev Limit? 167MPH.
What's the point? Well, this proves that what works on the street won't do much good on the dyno.
With the '06 Ranger runs, we proved the exact opposite - a MAXIMUM output dyno tune ran like fecal matter on the street. We kept the same tune and tweaked it with an hour of road testing.
With a 10% load (on the next run) the 2-3 wheel spin disappeared, along with the 2-3 rev-limit hit. This is a testimate to the inability of a dyno to duplicate road conditions without an eddy current load device attached to the dyno. If you are testing driveability issue or shifting, there must be a suitable load applied.
This is why we don't do "D-Stab" dyno runs, it is better to use 2nd gear [2 on the selector] for mudders or non-speed rated tires and follow up all other tests in the same gear.
Gears, ratios and changes:
Look at the difference in the TORQUE comparison between 2nd gear, 3rd gear and 4th. That is why 4th gear (1:1) is preferred. :nuts: Each gear change shows an ~10HP increase with each higher gear. This is explained in GROOLING detail all over the interwebs, but here's the "skinney": Each higher gear forces the engine to work HARDER, and this is expressed in higher numbers. Lower numercal gears ("Higher" gears - 3.08:1 Rear or 1:1 Trans gear) provide very little torque multiplication so the work is done mainly by the engine - the graph shows this work as increased torque (and HP). Higher numerical gears ("Lower" gears - 4.56 rear or 1st, 2nd) provide increased torque multiplication so the work is done by the gears and the engine is "loafing", this results in lower torque on the graph.
So, get'er tuned up and I'll see you at the dyno...
So, who needs a dyno run?:
Anyone that has modified their MAF, modified their vehicle so much that the PCM has to "re-learn" the idle if cleared, installed nitrous or forced induction, or wants to have hard evidence of the "fruits of their labor".
What vehicles can be run?:
Depends on the site doing the testing, the big issue being 4wd or AWD. These require a 4 wheel dyno and that is more expensive/harder to find. There should be NO LEAKS, NO SMOKE and NO MECHANICAL PROBLEMS. You should have a "fresh" tune up, with properly gapped plugs, good wires, good cats, good injectors, NO PINGING, good tires (plenty of tread, properly inflated), good O2 sensors (especially Pre-Cat), a working e-brake and topped off fluids. If you are prone to pinging, overheating or stalling, this is not for you. Time is money and some places charge heavy fines for spilled fluids. If you have any of these issues, you are really wasting your time and money. I recommend doing the tune up and MAF cleaning the week before if you want to compare a "Learned Stock" run, flashing the unit back to stock (for a limiters run) instantly gives you a "no-learning" profile since the KAM (Keep Alive Memory) is wiped clean on a reflash. A clean (or cleaned/reoiled) air filter is a great idea too.
What to bring:
Laptop, spare laptop battery (or DC-DC convertor!), LiveLink 4.17 (or better), USB device cable, digital camera, soft drink(s), pen/pencil, notebook, tuning manuals/reference material, common hand tools, MAF cleaner, rags and a well thoughtout game plan.
What to watch for:
The ABS light on most vehicles will come on since the rear wheels are turning and not the front, this is normal, and the light will go out a few minutes after leaving the dyno.
Scheduling:
Make plans well in advance, I actually scheduled for last Saturday, two weeks prior. Just so happens we got 4" of snow last Saturday, following massive flooding the week before. So, Friday I called to verify and then again on Saturday. Showing up early was well worthwhile as I got to see a twin-turbo Z05 Corvette... sweet.
Many places offer a discount for "groups", but you will get NO tweaking time and they will do 3 (or so) quick pulls. You may have time to swap tunes, but not tweak/adjust anything except the WOT fuel or timing via "User Controls" on your SCT device.
I had the SCT X3 PowerFlash tuner loaded with a modified stock profile (no limiters, but not "tuned"), an 87 profile and a 93. This allows for a quick transfer of files and a minimum amount of wasted time while strapped to the roller - that gets costly! Now, the vast majority of my dyno experience has been lowered Rangers, Explorers and Focii with "Z" series tires, so the standard procedure is to SLOWLY row the stick through the first 4 gears (all were 5 speed O/D), then stab the throttle at the lowest RPM you can get without lugging the engine. On an auto, I have a special profile that locks the TC and trans in 4th gear, deselect the O/D, and set the IAC up a bit to keep it from stalling on the dyno. Rev the engine to just over a grand in neutral and drop the selector in to "D". With the extra IAC air and the RPM's, it is enough to get the roller moving (preventing an embarrassing stall!) and you're off in high gear with minimal losses and no silly 4,800 RPM "flare" from the TC.
But, this is the first time I'm testing a lifted truck with 32" mudders. These are "S" rated tires which were recently balanced. This puts them at approximately 112mph, and the Focus (with 3.8:1 gears and 24" tires) hit 119mph, easily. We know most Ford trucks have a speed limiter at 87-95 mph (with factory tires), and that should be over 100mph with the 32's. So, since I'm doing a dyno article for another forum, I figured I'd go Barney-style; deselect O/D, drop it in "D" and stab the throttle (later referred to as "D-Stab" runs).
Here is the ugliness:
http://www.rogueperformance.com/pix/Explorer/Dyno_87_Oct_8-12-07_Baseline.jpg
What do we get out of this mess? Well, we can see that first gear is completely useless, the time is too short to glean any useable data. Second gear is nice, starts reasonably low and gets well over the magical 5252 (TQ/HP crossover) and shows until HP tails off. Third gear is a little weak, it starts late (just before the 5252 convergence, but after peak torque) and ends normally. Fourth is by far the sweetest gear for real numbers - unless you have a stock limiters. The speed limiter, in this instance, hit at 105mph, and at 4,860RPM's - much too soon. The reason for the 105mph speed limit? Start with 1 divide it by the 28” tire, times a 32” tire = 1.14 x the 92mph limit = 104.88mph - coincidence? Not! Notice the rapid drop in HP/TQ numbers? They correspond with the rapid increase in the AFR (18:1 at botton of graph) since the PCM pulls injector dwell time to limit speed and rpm’s. Major problems for nitrous and forced induction folks - this would be blown head gaskets for sure.
The other obvious signs are the radical spikes (increase) in HP/TQ at each shift. These are not only unsightly, but they fool the dyno computer in to thinking they are the peak HP/TQ numbers. The readouts stated that my peak numbers were 200.1HP and 221.23TQ, completely wrong. The true numbers were 181HP and 188TQ. I plugged these in to the “Rogue Dyno” and got 181HP and 189TQ - Hmmmmmm…..
Remember, these are "unlearned" bone stock PCM numbers, the torque numbers are low, but I attribute this to the lack of learning.
http://www.rogueperformance.com/pix/Explorer/Dyno_87_Rogue_Baseline.jpg
Now, compare these first two charts:
"Smoothing":
Notice on the first graph that "smoothing" is set to 5, this is the highest setting. Smoothing makes the chart look, well, smoother. It removes some of the jagged edges and rough spots in the chart. While this does look good, it is basically a lie. Now, look at the "Rogue Dyno" and you will see the staircase-like look of the run. This is because there is no smoothing, it is plotting the data as listed. Smoothing is adjustable in most dyno viewers (like WinPEP 7). To analyze the data - set smoothing to 1, to post on the web, set it higher.
What's the verdict, what did we learn?
-Safety first: 2nd gear only runs for any non-speed tires. I still prefer 4th gear for better data, but 2nd is perfect for mudders.
-Rev/speed limiters are pretty evil, annoying and unsightly.
-The Excell dyno works dead-on if the factory torque limits are untouched.
Now, for contrast, here is what most people expect to see:
http://www.rogueperformance.com/pix/04+Ranger/JLM.jpg
This is a bone stock 3.0L Ranger, Auto with the TC locked using that 4th gear trick. Sweet huh? No guessing, the computer posts everything you want/need. But, there is no way to get this with an auto trans (and "S" rated tires!). So, how did that first run come about if there are rev-limiters speed limiters and other evils in the stock PCM? Easy, you pull up a bone stock profile and change only the IAC, limiters, TC lock and trans lock functions. No timing tweaks or fuel tricks. While it is tough to get in there and resist the urge of changing everything, this way ensures a true before/after scenario. This means much more work on your tuners part, but one look at the results and I'm sure youll agree, it is worth the effort.
So, what to do? Put the selector in "2" and go. No fuss, no muss, but there may be some TC flare...
The before and afters here are a showing the added fun of a 75mm MAF and 14" K&N cone filter.
Notice, run one (-002 actually) is typical, late open loop. The AFR stays at 14.63:1 until 4,100RPM's when the TPS is well past 663 and the open loop timer has run out. Then it drops to 12.5:1. Run two (actually #14 of 15 runs that day) has WOT instantly rewarded with 13:1 for the duration of the run. While 11rwhp and 12lb/ft of torque may not seem like much, this has a stock exhaust and is running on 87 pump gas with no mods besides the MAF and filter.
http://rogueperformance.com/pix/Explorer/87_Oct_8-12-07_BaseTune_1-2.jpg
This is run 1 (w/ factory limits) and run 2 (no limits). Notice the 4th gear run is much longer, and goes 22mph faster than the tire ratings (135MPH)? Now, this is with oversized tires, and it will be regeared for 4.30's with the 33's, but the top speed will still be well over the limts of the tire's speed rating ("S" in this case).
This should MORE than settle the debate of 2nd vs 4th (or 1:1) gear runs for those of us with oversized tires.
If you have "Z" rated radials and want to have the "best" data - go in 4th, or whatever your 1:1 gear is.
http://www.rogueperformance.com/pix/Explorer/Dyno_87_Rogue2_Baseline.JPG
"RogueDyno" appears to be off by 4% with the increased output.
Start at 181HP, end at 188hp, increase = 3.8%, so this might be the problem.
Ladies and Gentlemen, it is my distinct privilege to introduce to you, the worlds ugliest Dyno chart!
http://www.rogueperformance.com/pix/Explorer/87_Oct_AFRTune_3.jpg
This was a 6 month old tune that was run on the street DAILY with no issues whatsoever. Put it on the dyno and what do you get? A bowl of spaghetti, complete with wheelspin, rev-limiter hits, 20+:1 AFR's and all sorts of foolishness.
Notice: The 5252 convergence is AFTER 120MPH, so this run would never show peak HP unless you went WELL above the the 112MPH tire limit. Where would we be at MAX HP? 142MPH. ...rev Limit? 167MPH.
What's the point? Well, this proves that what works on the street won't do much good on the dyno.
With the '06 Ranger runs, we proved the exact opposite - a MAXIMUM output dyno tune ran like fecal matter on the street. We kept the same tune and tweaked it with an hour of road testing.
With a 10% load (on the next run) the 2-3 wheel spin disappeared, along with the 2-3 rev-limit hit. This is a testimate to the inability of a dyno to duplicate road conditions without an eddy current load device attached to the dyno. If you are testing driveability issue or shifting, there must be a suitable load applied.
This is why we don't do "D-Stab" dyno runs, it is better to use 2nd gear [2 on the selector] for mudders or non-speed rated tires and follow up all other tests in the same gear.
Gears, ratios and changes:
Look at the difference in the TORQUE comparison between 2nd gear, 3rd gear and 4th. That is why 4th gear (1:1) is preferred. :nuts: Each gear change shows an ~10HP increase with each higher gear. This is explained in GROOLING detail all over the interwebs, but here's the "skinney": Each higher gear forces the engine to work HARDER, and this is expressed in higher numbers. Lower numercal gears ("Higher" gears - 3.08:1 Rear or 1:1 Trans gear) provide very little torque multiplication so the work is done mainly by the engine - the graph shows this work as increased torque (and HP). Higher numerical gears ("Lower" gears - 4.56 rear or 1st, 2nd) provide increased torque multiplication so the work is done by the gears and the engine is "loafing", this results in lower torque on the graph.
So, get'er tuned up and I'll see you at the dyno...