You really need to step back and reread the thread. For 3 times I Said the corrections are not somthing that you should obsess about. The car is moving faster and the RPMs are going by faster. Envirement wise there is going to be only so much the car can do. Untill you put in the stock air box and test back to back you won’t know. Also the tune take a few days to settle in.
Apologies as the learning curve is steap…
I got it when you said that correction especially for a tuined car is nothing to be obsesed about. My concern stems from my igorance as to when a correction might be an “issue”. Since I can;t define yet that line, I am most likely overeacting.
In any case, I get especially the fact that the tune may require some days/kms to settle in appropriately.
The below are today’s logs.
They were done with similar ambient conditions like yesterday but with a full tank.
Obviously what is worth mentioning is that first pull was a lot worse than 2nd (my understanding at least…), when the second was done about 5 kms of normal driving after the 1st one.
Yet again in the upper rpms, we still don’t see a smooth output in terms of hp (as sakimano said it would most likley do). I believe it still has to do with teh lack of stock airbox.
In any case i think the gains are significant, can be proven with this one as well as the proof that IAT makes a lot to the performanc eof the car. Since 1st pull had max IAT of 46 Celcius and 2nd pull a max of 38 Celcius (both at low rpms). IAT at max MAF/sec stood respectively at 37 Celcius and 34 Celcius.
Must admit I am quite happy with the feeling…
Can you please confirm my findings calculations wise as regards the second pull? Numbers in terms fo torwue and HP seem a bit high??
https://www.dropbox.com/s/9ju4zcd2e0kch8r/01092014.xlsx?dl=0
Your 'tq numbers are directly in line with that others have posted.
This should be a good example of looking at your air box situation. Your 115 deg at the start of the run and the temps drop over 115 over the range of the pull. Normally the temp range is 4-8 deg of range your double that.
I know it’s hard to let of go the panic on the correction favors. So many have miss represented the entire idea. When you see them different per cylinder that’s a good opportunity to take and swap plugs and packs to see if the difference follows. Inspection of carbon on injectors or runners is important. And temperature temperature temperature. Is always going to create a environment where it’s harder for the motor to achieve optiomal ve so expect to see the continued adjustments and more adjustments for safety because you have the JHM tune.
Looking at the logs the car looks much much faster. I bet it pulls hard especially when you consider your driving around in 100+ degree temps.
It pulls hard for sure… And temperature is temperature as you said.
I don’t think that spark plugs and carbon can be issue as those were changed/cleaned a few kms ago. In terms of injectors i can’t tell. Perhaps…
The 2nd pull is exactly in line with what i would expect from a tuned car. Should i be concerned at all about the lamda correction being in upper 10s of neagtive value? (Car running too rich…)?
Second could the HP calc of 455 be correct?
I have similar mods to you except I have the std airbox.
This was from a few weeks ago.
BP98 fuel 3/4qtr full.
Outside temps around 8 deg c.
https://drive.google.com/file/d/0BwAYocYW-vDjWFRia3FRb01zVGc/edit?usp=sharing
holy shit intake air temps are 40 c?
That’s crazy temps.
The negative value mean the car isn’t needing as much fuel as is available. With temps over 100degrees the air is thinner so the less dence air won’t require as much fuel.
Guys apologies for being away for quite some time…too frequent travelling, 3 ladies in the house…and you get the picture…
Anyways foudnthe time today to devote it to the car and switched from the Revolution Air Intake back to the stock airbox.
The Stock air box has a deleted valve so it is a plai airbox. …it has been heat shielded with specialty tape and installed.
Right before we installed it I did a pull with teh Revoltun Air Intake. As can be seen by the below comparison chart, HP @449, Max MAF @ 353gr/sec. Max Intake Air temp at 36 Celcius. Once the Stock airbox was intalled, we did another pull, same conditions, results were quite different. Max HP @ 419, Max MAF 310gr/sec, MAx Intake Air Temp at 48 dropping to 36…
There is obviously in my mind a restirction in air and a lesser protection from heat vs. the the previous setup leading to a drop of 30hp.
https://www.dropbox.com/s/4kec3aaadihnndu/13092014_stock%20arbox_not%20connected%20caf.xlsx?dl=0
https://www.dropbox.com/s/leawn81muzs0su0/13092014_Revolution%20Air%20Intake.xlsx?dl=0
https://www.dropbox.com/s/7d2vt3bi5pycim6/13092014_stock%20arbox_connected%20caf.xlsx?dl=0
https://www.dropbox.com/s/u1vgh2hlzmimisv/Comparison.jpg?dl=0
The files connected and not connected CFA actually refer to two pulls, one with teh CAF direclty connectd to the airbox intake and the other without the direct connection.
Based on what I am seeing is that the car has a lot smoother behaviour on high rpms but it is loosing power with the stock airbox despite lower intake temps.
I can look at these later but before I do. Did you close odd the opening on the air box that bleeds off into the fender? Your air box is built to remove some of the air pressure.
Also the temperature difference is huge. Remember pulling in hot air the air is thinner so there will be a dissperency in the maf readings.
Thanks in advance for looking at the numbers.
In the “connected” pull , the ducting hose was slide inside the airbox hole. In the not connected one the ducting hose ws left a couple cm away from the airbox entry point at the fender.
Hope that makes sense…
Also if you look at the IAT btw the stock and intake, the first is about 4 degrees celcius lower and still 30 hp down.
So same temp, lower maf reading for stock airbox
I don’t know what your stock air box modifications look like but your going to need this.
http://audirevolution.net/forum/index.php?topic=183.msg1796
If you didn’t close the fender area it effects intake air speed. Read the first page. It has part of the air box study glide from Audi.
ok I didn’t have long to look but its what you would expect.
The stock air box actually has the air temps going down during the run and the evo intake has them slightly going up.
when you look at the averages and not the spikes that are going to be more exadgurated with a open element due to the uneven flow. We can track it and its about even though the rev range
RPM OE SAB
1900 37 29
2500 51 47
3000 62 52
3500 74 70
4000 89 80
4500 90 91
5000 109 100
5500 118 114
6000 132 122
6500 140 132
7000 152 147
7500 153 150
8000 176 150
All this seems like its an open and shut case. When you track the acceleration the Air box is faster but the OE has more calculated hp and TQ. Why. Thats the other part of the calculation you need to look at.
Engine load This tells you why you have more MAF with the open element. Your log was possibley up a hill or there was more grade or a head wind. Add more people to the car and your MAF readings will go up because your motor load will go up.
Lets look at that as well. This is showing the motor is having to work harder for whatever the out side conditions are. Most of the time this indicated up hill or more weight or resistance. Either way this shows why your seeing the offset in MAF reading. This further shows how impressive the air box is. Its got almost 10% less load but is still pulling in the same amount of air. And the temps are dropping in the stock air box.
Motor load
RPM OE SAB
2000 80 70
2500 93 82
3000 93 82
4000 93 82
5000 93 85
6000 97 89
7000 96 87
8000 90 83
In the end here. Close off the opening in the air box don’t allow the air to bleed off in the top end and your going to have even better results.
Really appreciate for you posting this… Hadn’t seen it before!
Regretfully i did not close the fender intake, thought it was useful for the air pressure.
will read the entire post and fix it accordingly. Thanks again
Job done. Closed the fender inlet, opened up the front grill one, connected the caf duct hose to the bottom inlet of the stock airbox and look forward to logging it this afternoon.
Will post the results later today…
My understanding from your thorough analysis is that the car does not struggle that much to produce power so it is better in that aspect. But what about top HP and torque?
Had the chance to drive it briefly after the installation and i don’t think it will yield similar results in terms of torque and power with the open intake…
Let’s see what the numbers say this afternoon…
You’re potentially misunderstanding. The calculations of hp and tq are getting skewed. What Justin is saying is correct. Try driving up a steep hill, watch your MAF readings go up watch the hp and tq number climb in that scenario as well. The load is important. The logs you’re doing are nice but almost irreverent other than entertainment. To show how inaccurate these tests can be. Log 3 times in a row. Give some time to let the car rebound a little bit. You will find the exact same swing in data. The numbers will be all over the place. If you look deeper into the logs you will see the acceleration between the two is closer then the calculated hp and Tq gap would advertise.
Log in 3 different spots and you’ll get 3 completely different results. If you want to try and log to help convince yourself that the aftermarket intake is better, just save the logging and time and just tell yourself its better. The stock air box if used properly and modified accordingly will produce the best over all results.
If you really want to prove this, even though it’s already been done and tested several times then go to the track. Set the car up one way make 3 passes. Switch and then make 3 passes on the different set up. The stock airbox can’t be beat as far as best performance potential.
Trust me, everyone here wants your car to be as fast as possible. You already spent the money and already have the parts, nobody is going to want you to put something on your car that isn’t going to help make the car as fast as it can be or run at its best.
Since you posted the logs and they are there. Let me help point out exactly what I’m talking about.
Open element 5000-6000= 597.7 6000-8000 = 499.8
Stock air box open 5000-6000= 595.9 6000-8000 = 496.2
This is the power sweet spot. The difference isn’t enough to even call a difference. When you add in the fact that the Air box is allowing the temperature of the air to drop and its offering you more protection, that starts to open up the gap. With the closed off air box you should see more gains.
Count thank you for the feedback. I apologize as i am still learning if it seems i am missing anything.
You put it very well and this is my understanding too… The stock airbox is an overall better application if you take into consideration all elements and not just only TQ and HP since you cannot duplicate conditions each time.
Correct me if I am wrong when i think that if the intake is used, you may get some better hps and tq but the engine will be getting hotter hence decrease in performance will take place sooner. On the other hand the stock provides a smoother and more steady behavior the longer the car is used.
I truly believe you guys have been there and done that. I am following the experts since i acknowledge my ignorance and not shy to admit about it. But for me to learn, it takes more a practical approach rather than simply reading…i prefer to get my hands dirty and understand things via practice. So it is not that i am looking to confirm what you guys say either tell anyone that i think the aftermarket intake is better…it is simply that i like to see how things work first hand.
The difference in the way the car operates is evident…it is smoother and this is important. My previous comment is that for some reason the car felt more “nervous” and “aggressive” with the aftermarket and it feels a lot smoother with the stock on driving conditions and not WOT.
First off, don’t feel bad ask questions but make sure to read and try to understand what what others have said. They are trying to help you do what you’re looking to do.
Never apologize, AR is about learning and its hard when you come from sites that don’t want to do anything but hope things work and hold onto data that isn’t good for anything else but bragging rights.
I think part of the issue is, you actually are believing in the TQ and HP readings you’re getting from the Open intake. Both me and Justin just showed you that the TQ and HP numbers don’t add up. It’s a calculation that is getting a bump due to the flare ups that are normal with open intakes.
Again, No, I just showed you that in the world of acceleration when you looked at the 5000 RPM to 8000 RPM even though your open element intake got a huge spike in MAF readings that RPM per second, it was no faster then the stock air box.
I really support you getting your hands dirty and doing your own testing. The biggest issue is, when you did the testing you we not understanding the full results, you need to look much further and when you actually looked further and did the acceleration testing (as that’s what you want to improve) It showed what the real picture was. That picture said, even though the calculation said there is this big hp and tq difference, there was not a measurable difference in acceleration. The reason there was not a difference in actual acceleration was because the hp and tq number isn’t accurate.
The car will feel better with the stock modified air box as you have said. The open element isn’t consistent, you’re getting blasts of hot air and then MAF spikes due to the air not being straightened as its coming into the filter and MAF.
He is referring to RPM per second… IE how quickly your car is accelerating through the rpms.
Using the maf g/sec isn’t always the best way to measure acceleration. The rs246 guys love to but it’s flawed.
One example was a member who tested his car with stock exhaust… And then tested with a 2.75" catless JHM exhaust.
Same road, same spot etc.
The stock exhaust had better maf nunbers by about 10 g/sec, however the jhm exhaust accelerated much faster.
On my own car I found that my JHM exhaust gained me about 20-25 hp (real hp not logging hp) based on how much I accelerated faster (0-60 mph, 60-90, 0-100 etc).
Point is you need to focus on how your car is actually accelerating rather than getting wrapped up in a number from a log parameter.
Another way to look at it is, if I sell a tune and exhaust that makes your car accelerate faster by a full second from 0-100 mph, but your maf and hp logs will look worse… And I sell another tune and exhaust that won’t make your car any faster but your maf and hp logs will look great, which would you purchase?
Easy answer… You’re buying acceleration parts so you want the first one. Focus on acceleration.
Now i completely got what you say.
Whilst i always thought numbers were irrelevant (ie when i flashed the ECU could not think it gave 450hp from 390hp prior but most certainly the difference is big), but “differences” are important. The problem is that i had no idea which variable is the major to look at to get an ideas for it. Now you showed it’s the acceleration rpm/sec.
Now i totally get it…
Thanks a lot guys