I ran into some serious situation that I don't understand myself. I'll try to explain the best I can.

Vehicle: 2003 Infiniti G35 Coupe 5AT
Milage: 56K miles.

All Dyno pulls were done in 3rd Gear.

A. Phase I: Stock motor with a long tube Cold Air Intake = 223whp on Sharif's DD. AFR = Not Measured. Temperature = 90 degrees. This was back on Forged Performance Grand Opening day in Atlanta.

B. Phase II: Installed Topspeed Ceramic Coated headers, 5/16" Spacer, MREV2, and Polished Upper Plenum. = 225whp on MSPi's Dynojet. AFR = Not Measured. This is about 1 month after Phase I.

C. Phase III: MSPi and TDF fabricated a 2.5" true dual headerback setup for my car: = 242whp on MSPi's Dynojet. Within 24hrs of Phase II. AFR = 15 (MSPi's niffer). this showned a gain of 17whp from Phase II.

D. Phase IV: Installed UTEC (bought from Sharif), on Map 0 = 240whp (2 weeks after Phase III). MSPi tuned the car, made 244whp, AFR = 12.7 (O2 Wideband sensor on the secondary). Since MSPi isn't well experience with the UTEC, I consulted with Sharif. He said something wasn't right. I shoud made more power when tuned, not staying around the same. I decided not to go with that map from MSPi and switched back to Map 0 instead and get an appointment with Sharif at Forged Performance.

E. Phase V: Sharif quickly tuned the car. Baseline before tune = 226whp with AFR = 14.5 (approximately). After tuned, = 237whp with AFR = 12.7-12.5. This raise a question: All those mods only = 3whp gain before tune?. Sharif's suggestions are: Different dyno day, condition of the weather, CAI is hurting the performance, etc. However, at Phase I, it was on a hot summer day at a scorching 90 degrees. This is on a cool day at 65 degrees.

F. Phase VI: Took the car to MSPi for a redyno and diagnose today. In theory, I should be making 13whp above the 242-244whp mark since Sharif tuned the car. MSPi dyno = 242whp, AFR = 12.5 on their Sniffer. Temperature = 50-55 degrees. I then tried to prove Sharif's theory about the CAI and replaced with the Z-Tube-like intake. MSPi's dyno - 237. AFR = 10.7 No ECU reset. UTEC is still on map 1 (Sharif's tuned_

Now, the million dollars question:

What's really going on?

1. Why did all those mods only made 3whp according to Sharif's DD? From MSPi's dyno data in phase II and Phase III above we see the extremely large gain when the exhaust freed up all the air flow that the engine breathes in, going from 225whp to 242whp. I do not believe these mods doesn't add any power. These have been previously dyno proven before. Whether they're only 5-10whp, they do make some power.

2. Why I didn't see any gain of the tuned result when I brought it back to MSPi today. What's really going on? Why did it show gains on Sharif's dyno (from 226 to 239)?

Could it be that the baseline that Sharif took before he tuned the car wasn't correct. Could it be that the baseline can actually be 239 and the tuned data only corrected the AFR while staying the same? I can only see this as to to solution to question #1 above: that the car actually made some gain, it's just that the wrong baseline caused us to think that we didn't make any gain. I know that MSPi's dynojet is consistent (measure the same 3 times in 5 weeks time frame) and that they cannot be manipulated.

All professionals, please help to the question of my headaches. I may not be a guru or expert in the VQ platform. But I do know a fair amount of technicals so that I don't do things the wrong way.

Thanks for taking this challenge.

 

UTEC Map and MSPi's Dyno are to be posted. I'm still awaiting Sharif's response on the dyno data as well.

 

it's not all about peak number. area under the curve counts a lot, and that's what you gain the most out of tuning.

 

Pick a shop to dyno and stick with it. You're looking for net gains, not absolute numbers anyway, and as stated, area under the curve will fluctuate widely even if not the peak power. The temp/humidity will make a difference. IMO, comparing the two dynos after making changes w/o resetting the ECU won't give you any reliable/repeatable data, and is NOT a good indicator of what each mod is worth.

 

Here's the baseline dyno of Phase I:





Following is the Phase V, Stock Baseline vs Tuned:



Here is Sharif's advice:

"Hi Kevin,

THe baseline numbers during the dyno day were done using road speed in order to calculate RPM. The peak number should be unchanged, but using road speed can distort the shape of the graph, as you can see in this comparison. I am not sure how much help these dyno charts will be. The only assumption we can make, is that you baselined 223whp on our dyno, and then 237whp after your mods, and tuning with the UTEC. The numbers can expected to be about 10% higher on the dynojet."

Therefore, according to him, I should be expecting a gain when I went back to that dynojet from MSPi. However, the results are still the same. MSPi closes today, so the earliest I can get the dyno data is Tuesday.


Also, with regards to undrgnd's opinion: ECU was reseted after each modification from phase I to phase III. Between Phase III and Phase IV, it doesn't have any reset as we let the ECU learned all the new mods in 2 weeks of driving (110miles/day, about 1200 miles total). After Phase IV was unsucessfully made any extra power, we were resorted to ECU's stock, map 0 on UTEC and carried on to phase V.

However, the vehicle didn't see any miles but that one day I drive to Forged, which is 50 miles max. Therefore, phase IV and V are seeing the same condition.

Between phase V and VI, there aren't that many miles but may be 100 miles, due to the fact that my brakes really worn out and that I don't want to drive it around much. So between these 2 dynos, Sharif's DD and MSPi's Dynojet, they're seeing the same factors, similar weather condition, and not many milages in between. Therefore, if I see the gain in Phase V, I should be seeing the similar gain in Phase VI as well. EVEN if I drive the vehicles for 10,000 miles, the gain should still be the same, because it's TUNED and we do not rely on the ECU's learning curve anymore.

 

Here's a quick excel-ed version of Sharif data to match up the baseline (phase I) vs Tuned. I'm still awaiting his pretune Baseline vs Tuned baseline graph.

 

It looks to me that the throttle isn't opening up 100%. You may want to recalibrate that, if you haven't.

Also - have you changed your redline at all? The peak RPM is low - so it looks like that has not been done yet. Most of your mods are top end power mods, and another 500RPM will be all the difference - especially in your peak HP numbers.

As others have stated though, it's not entirely about peak HP...power under the curve and overall power flow/increase to redline/shift point is what matters most.

Rick

 

Thanks Rick,

I don't think Sharif opened the Redline.

Also, how do I go about recalibrate the throttle? If it's just the matter of Turn ignition on 2s then off 10, I've tried that. The car is idling at 600-650rpm, which is lower than what it was before (750RPM).

 

Hmmmm.....

This is a tough one. The first thing to note is the complication introduced by changing mods and changing dyno.

If you were to "Map Out" the progression of modifications you would have a series of points going from point A to point B. The problem is some of the in between data points are lost and there are holes in the map. This is making it very difficult to say exactly which mod did what.

But what you do have is phase I Vs phase V. ---> +14HP
And phase II Vs phase VI ---> +19HP

My personal experience with TS headers on my G35 showed only ~3HP so I wouldn't put much into that one.

17HP from a header back system is possible, but that's reaching into the top end of the known spectrum. There may have been some ECU drift involved in these numbers.

As for loosing 2HP on the other dyno with Sharif's tune may be possible because its within the margin of error, but I don't know how to explain the gains seen on his dyno Vs the gains not seen on the other dyno.
And a descent tune will always make gains.

I recall that you also changed tires too. Where within the list of phases were the tires changed?
Do you know if the tires had any difference in diameter or mass?... Please research the tire specs and report back. This could change things by some unknown amount if they are significantly different. I imagine they would have to be substantially different to have an effect.

I also suspect the ECU may have been playing its usual games on you all the way up to the point of the UTEC install. Some cars (ECU's) seem to stay in performance mode, while others tend to gravitate toward lazy mode.

My G35 ECU is a bit on the lazy side and is easily woken up after a ECU reset.
My 350Z ECU stays in performance mode all the time.
Other Z's or G's are quite happy in the full performance mode and stay there all the time. In this case, a ECU reset won't do anything. I've seen both cases on the dyno but I'm getting the feeling your ECU may be drifting from one state to another.

In any case, this is very difficult to figure out with so many disjointed variables at work. There are several comparable data points and several that are not. The ones that are not comparable are the ones we really need to complete the picture.

Certaintly in the future, stick with one dyno for all other comparative and mapping tests. Also try ECU resets before hitting the dyno. You have the UTEC which should help eliminate the nonsense of the ECU, but I would try a reset on the dyno anyways.

Can you overlay the dyno plots that you do have? It looks like you got a good increase in area under the curve as shown in the excel plot. And that's worth much more than 3HP at the peak.

Tony

 

You made power on Sharif's dyno, then went to a Dynojet to expect the same and didnt do much. You dont seem very knowledgable on dyno's (but we are all here to learn so you hopefully will learn something from this situation) so Im going to ask a few questions I didnt see you address that can most definitely affect the "gains". Baseline at Sharif's was 223whp, after mods and tuning = 237whp. So then you go back to the Dynojet and expect 10% more. What correction did the Dynojet use? To fairly "compare" numbers from 1 dyno to another (this really shoudnt be done as it has no validity) you need to understand how Sharif's dyno is set-up. It is set to a STD (standard) correction to account for temp, thats it, no "added" Dynojet correction hence the lower number. To "fairly compare" at the Dynojet you must not look at actual (non corrected) or SAE corrected numbers, you must have the dyno operator change the correction to standard (STD) to be "fair". That way you are having numbers corrected basically the same but will get different dyno readings. So, go find out what correction your shop used every time you dyno'd so we have a better idea on whats going on. If you have the dyno files, you can upload Dynojet Viewer and change the correction yourself to find results. Look into that and post back.

At the end of the day you only went to the Dynojet for "bragging" rights as you know you made gains on Sharif's dyno (who is set the same way for everybody 100% of the time) who we all know isnt set up to inflate egos, dynos are tuning tools and when you compare from dyno to dyno $hit can sometimes not make sense, exspecially if you dont know about corrections. I look forward to seeing what correction your DJ plots were set to.....

 

Thanks Tony for the help, I'll try my best to answer your questions:

 

Alberto - Thanks for chiming in. Here's what I know.

1. That Dynojet is NOT SAE Corrected but STD corrected. MSPi always keeps everything closest to real life as possible. I'll double check on that.
2. I did not went back to MSPi's Dynojet for bragging rights, I don't really care about the numbers, my only concern was to diagnose Problem #1: Why we only see 3whp gain on Sharif's dyno with all those mods: Phase I - 223whp vs Phase V - 226whp (pretuned).
3. On that same dynojet, pretuned was 242, and we still measured 242 after Sharif tuned. That's why I'm even more concerned, this raises Problem #2: If you read it more carefully, you'd see my question clearly and understand it clearly as Tony did. My words may be confusing, but I tried my best to explained the 2 main problems that I'm having.

I'll try to get the Dynojet plots ASAP in hope of clearing up all the confusion I'm having.

 

Were all pulls done in 5th gear? If not, that makes a diff in #'s as my car and many other Z's/G's surprisingly dyno higher in 5th than 4th. I have a feeling the corrections may have been different when you went back to the DJ. Any wheel/tire changes?

 

You need the TS Lspec reflash...

 

Alberto - All were done in 3rd grear as this is a 5AT Non-Revup
Rick - So, regarding the Throtle/idle issue, I'd need a reflash afterall? I was trying to avoid that I heard that Infiniti can do it with Consult-II

 

1 - your pulls should be done in 4th - that IS the 1:1 ratio gear on a 5AT. Numbers will be higher in 3rd as the ratio gets shorter.

2 - there are things the reflash will do and change that the piggy back cannot do...and they are performance gain related.

Check out TS's website for the details.

Rick

 

Most Dyno Jets have an internal Automatic Atmospheric calibration that will automatically be calibrated internally from day to day, without user input. The DynoDynamics is quite the opposite, in fact upon startup it requires the user to input the Atmospheric conditions using the supplied weather station. I demonstrated to a group of customers this weekend how a slight variation in the Barometer setting can manipulate the HP output. I demonstrated how a car that made 245whp Standard DD uncorrected numbers with only an Atmospheric correction, was able to make 386 whp with a change of the barometer reading on the Atmospheric corrections
What might have happened here is 2 or 3 different scenarios.
But first off, you can not go by your original Dyno at Shariffs on opening day if he used the speedometer setting to simplify setting up cars for the dyno day. This method takes into account your particular RPM in the gear your dynoing in, in relation to the speed the car should be going. For example, if you put the car on the dyno and drive in 3rd at 50mph, and you rpms are 3860, your calibration would be 3860/50 on the Dyno. However, different things come into play such as tire size, gearing,wheel size ect..And the slightest variation of even .5 mph on the calibration makes a difference. Therefore I would not even use the inital reading for arguments sake, since the claibration may have been done an a 6mt car prior to setting up your car on the dyno. So to use this number for comparison sake would be slightly inacurate.
The second thing i would look at, is the dyno immidiately following the exhaust install, how accurate were the readings? And what was the Atmospheric corrections in relation to the day you went to get tuned??
It is highlt unlikely you lost gains going from dyno to dyno, I personally have never seen a UTEC allow the state of tune to change, unless you picked up some knock and the UTEC kicked into MAP STEP KNOCK RETARD..Have Sharif check the parameters and see what this is set to, and also the sensitivity of your knock feedback settings. You may either be knocking or picking up false knock somewhere causing the UTEC to globally retard timing once you left sharif's dyno..One way to know is to re dyno on the DJ, with 93 octane and dattalog your knock counts, then try redynoing with 100 octane and see if the power comes back.

 

Thanks MRC for more explaination and clarification.

1. With regards to Stock Baseline Dyno vs Tuned Dyno, I'd have to let Sharif comments on that. It may be very likely like you said.

2. Phase III dyno of 242hp was within 24hrs of the exhaust install. Installation wasn't completely finish on the first day so I brought it back the 2nd day to finish, then redyno. The reading is pretty accurate as we see on Phase IV, which is 2-3 weeks and 1200+ miles later, we dynoed the same on that same dynojet. With regards to the Atmosphere correction, I'll double check on that. They should be corrected.

3. Sharif said he'll take a look at it again and see what's really going on to why we're seeing the same number as un-tuned on MSPi's Dynojet.

 

My name is Mike, an i work for Mainstream Performance. We are the ones that fabricated the custom exhaust an dynoed Kevins G35.

Here are the run Files that i have for his vehicle. I never really cared what he made on someone elses dyno because i know that different dynos, different days, mean different numbers. Dynos cannot be used to compare against each other. To many limiting factors. What they can be used for, is an apples to apples comparison.

IE: if you dynoed 220whp on MY DYNO. we did a modification to the car, and it made 230whp. that means you saw a true 10whp gain.

Now, lets say you BASELINED 220whp on my dyno. I make a modification to the car, an you take it to a different dyno to see what the "mod" added power wise. If it dynoes lower, does that mean it LOST power from the "mod"? ABSOLUTELY NOT because you are comparing two different machines.

thats why i insist on sticking with ONE dyno an ONE shop. Hell , if your only after NUMBERS, dynapacks give out the highest readings, but numbers are only HALF the variable. If you dyno on my dyno an make 250whp, then go to a dynapack an make 270whp, assuming no changes were made to the car, is your car FASTER, did it really make MORE POWER? ABSOLUTELY NOT. you just had two different "measuring sticks".

Having said that, something is odd about kevins car. Theoretically, if it was tuned, it should show a bigger number on our dyno. however, it was a different day an it was BITTER COLD so perhaps that is the reason. Also, his car dnyoed this past sunday during our DYNO DAY , and some other cars WERE down on power from what they normally see. Our Race car usually make 630-640whp at 29psi, he made 32psi of boost an only made 601whp.

Here are his Dyno Charts:
SAE

BLUE RUN 2 IS BASELINE WITH HEADER AN STOCK EXHAUST
RED RUN 5 IS BASELINE WITH HEADER AN MSPi EXHAUST
GREEN RUN 32 IS MINOR TUNING WITH HEADER AND MSPi EXHAUST

STD

BLUE RUN 2 IS BASELINE WITH HEADER AN STOCK EXHAUST
RED RUN 5 IS BASELINE WITH HEADER AN MSPi EXHAUST
GREEN RUN 32 IS MINOR TUNING WITH HEADER AND MSPi EXHAUST

We dont tune UTEC, never have, not what i specialize in. so the TUNING done was extremely minor, as i was trying to figure out the system really. After about an hour, i told kevin to take it somewhere that had more experience with that system so his money wuold be better spent.

Hope that clears up some confusion

 

Thanks for posting the data Mike. I fyou please, can you please add the plot that I dynoed last Sunday to this graph as well?

To clarify things up.

Run 2 = Phase II Dyno - Before exhaust
Run 5 = Phase III Dyno - After exhaust
Run 32 = Phase IV Dyno - 2 weeks later, stock ECU on the exhaust. This run is NOT on MSPi attempt to tune the car.

Mike, can you please add 2 more plots:

1 of 246hp when you guys attempted to tune the car. And another one was what you measured the car this past Sunday, after Sharif's Tune.

Thanks again.