grambles423
Automotive Engineer
Also, the intake logs from the technical sticky can be pulled here too
6
GTI Data Logging Compendium
- Thread starter A_Bowers
- Start date
A_Bowers
Moderator
Ya mean these
Its been quite a while since I've posted a Technical Understanding thread with some hard data and calculations to further feed our minds. Since most of the conceptual basis of the earlier threads were.....for the least bit.....theorhetical and quite possibly boring, I decided to do a little experimenting (with help from NS01GTI) to collaborate data to compare stock intake with drop ins and aftermarket intakes.
Test Requirements:
- APR K04 93OCT Runs (~366hp ~380tq)
- APR IC (will affect IATs but will remain consistent)
- 3rd and 4th Gear Runs (Data was collaborated in 4th gear due to sample size and output.)
- Consistent Ambient Runs (Or at least within a +/- 5*F Tolerance from our Nominal)
- Stock Intake is a CBFA Intake with no modifications
- VWR Drop in incorporated the deletion of the baffle at the bottom of the air box
- Carbonio was done in two stages: Stage 1 only and Stage 1+2 (PENDING DATA COLLECTION)
- Same stretch of roadway was used
- Variation in Starting RPM Ranged from 200-300RPM in 4th (~2200) and 200RPM in 3rd (2700).
- Redline will be assumed as the normal redline but some logs will be shown past 6600RPM due to the DSG Stage 2 flash (7100RPM Redline) that was added mid testing (DSG Tuning added Post VWR Drop in, Pre Carbonio Stage 1)
Results:
Stock Intake
3rd Gear Run:
4th Gear Run:
Thoughts
Immediately you can see that the stock box will not hold boost properly throughout the entire rev band. Sort of a "dying effect" much like the stock turbo sees.
Boost control is smooth in the midrange which correlates with the peak condition you see intially. Still, the "butt dyno" registers a loss in the system and takes away a lot of the "raw" manly feeling of the K04. You can see the discrepancy from requested and actual better in the 3rd gear log.
Some thoughts in my build thread about the construction of the stock box:
Takeaway: Stock box is not efficient enough to hold and maintain boost through the rev band an on into the upper RPMS. Also, stock box shows higher IATs up the RPM band even with the APR IC.
VWR Drop In Filter
4th Gear Run:
Comparison
So what does this mean? It seems that the drop ins will actually help alleviate some of the down low restriction and allow the turbo to spool quicker, but will not give any added flow up top. Since in fact that two MAF rates look IDENTICAL at redline, I would be safe to say that its simply not worth it. The boost still dies sharply after the "point" has been reached where the flow just cannot keep up with the requested pressure.
Dont mind the lower value for the Drop in filter for boost at the final point. This could be % error in between measurements on different days. The point to take away is that it did not ADD any "breathing" at higher RPM. Ipso Facto......the stock intake box is just too damn restrictive for the boost to keep matching requested values at the last 1/3 of the rev band.
Takeaway: While a drop in allows for some down low flow to spool slightly quicker, up top the car still cannot meet its requested boost. You're still choking the car at upper RPMs
Carbonio Stage 1
4th Gear Pull:
Looking over the logs, the carbonio decreases lag and onset WAY faster than the VWR drop in and Stock filter and flows more in the higher RPMs, thus allowing to hold boost easier (0.29psi discrepancy between Specified and Actual)
Peak MAF Readings
Stock Intake: 236.4
VWR Drop In: 235.8 *******Difference can be error between measurements
Carbonio Full: 258.8
Difference in Peak and Redline Hold
Stock Intake: 5.51psi
VWR Drop In: 5.61psi
Carbonio Full: 3.9psi
Difference in Requested and Actual at Redline
Stock Intake: 2.2psi
VWR Drop In: 2.03psi
Carbonio Full: 0.29psi
Takeaway: Data speaks for itself. An aftermarket intake is definitely worth while. Especially one that is sealed off from the engine bay and only pulls cold air from outside the vehicle.
Carbonio Stage 1 and 2
Take Away:
1) More MAF: ~6.2g/s higher (On a 9F hotter day)
2) More Boost Requested: Almost 1psi higher in the upper RPMs
3) Faster Request (Quicker Spool) in Lower RPMs:
4) Slightly Faster Response to Peak: 200RPM Sooner
5) Higher MAF Readings in the Mid Range Except under boost control
6) Equal Tempearture discrepancy from Start to Finish: 5-6*C
All in all the turbo is working less strenuously to boost better but the peak will come quicker asking for the Wastegate to dial it back quicker. This is mostly why people find hesitations in after market intakes besides the Stage 1 portions. However, I dont find too many driveability problems with this.
Additional Intake Comparison Data (Carbonio vs. Modshack)
Thanks to the help of NS01GTI, we were able to get an accurate depiction of the clear differances between the two common intakes seen on this forum. One for Noise control, the other for high performance. Its ultimately the end user's decision to make a choice and what they would like, but for some fun, we decided to take the same data that we did in the previous setup:
4th Gear Run Carbonio:
4th Gear Run Modshack:
Comparison Graphs:
What I immediately saw was the discrepancy in reuqested boost values and actual values again. It seems that the Modshack, while not having the restriction like the stock box, still shows upper RPM boost loss from requested. MAF vales were also very considerably different in the midrange that we couldnt just say there was "variation in the runs" Almost 50-60g/sec more.
The driver also noted the "butt dyno" difference between the two. At upper RPMs the car just felt out of breath.
A quick thought about the sound differences:
Takeaway:
1) Carbonio has more mid range MAF and a quicker spool time.
2) Ambient conditions were different to each run but both IATs got down to the same temperature (~33*C)
3) Modshack has an almost 2psi difference between requested and actual at a higher RPM. The Carbonio seems to hold the boost more.
4) Carbonio log was started at a lower RPM, yet spooled quicker than the Modshack which started almost 200RPM quicker. The Carbonio log was the "hotter" of the two logs in terms of IATs
Conclusion
All in all this was a very fun excersise and it really showed some similarities and differences amongst OEM design, drop ins and aftermarket competitors. While it was VERY hard to keep some variables consistent, we still managed data that can be judged as sufficient for analyzing.
Furthermore, even if the data speaks so much, it helped me (and probably others) understand more of the flow dynamics involved in our little TSI engines. Where's the performance compromise? Where's the sound compromise?[/QUOTE]
timneedscoffee10
Go Kart Champion
Good deal... I'm going to log tomorrow, so it's great to have some independent reference material to compare against!
I'll most likely not post mine here until I get my new clutch, and break it in. The clutch slip causes odd looking dips mid-run... But I'll definitely contribute here in the next few weeks.
:thumbsup:
I'll most likely not post mine here until I get my new clutch, and break it in. The clutch slip causes odd looking dips mid-run... But I'll definitely contribute here in the next few weeks.
:thumbsup:
A_Bowers
Moderator
I can't take all the credit. It was more John's idea than anything, I just put it all together.
John@Unitronic
Go Kart Champion
Great thread. Looking forward to seeing the data. If anyone needs assistance graphing, etc., email me.
As for the logs, might I suggest the following as a general reference...
Use the "Adv. Meas Values" logging function and enabling "Turbo" mode for higher resolution. You can log 12 channels at once using Adv Meas Values.
001-1 (Engine Speed / RPM)
003-2 (MAF)
003-4 (Ignition Angle / Timing Advance)
020-1 (Timing Pull / CF Cyl 1)
020-2 (Timing Pull / CF Cyl 2)
020-3 (Timing Pull / CF Cyl 3)
020-4 (Timing Pull / CF Cyl 4)
031-1 (Lambda [x 14.7 for AFR])
054-4 (Throttle Plate Angle %)
114-4 (N75 Duty Cycle % Actual)
115-3 (Boost Specified)
115-4 (Boost Actual)
I would recommend only doing the runs after engine is to full operating temperature from 2000rpm to redline for the most accurate results. I prefer 3rd gear because its much safer for the street as the speed as you reach redline is lower.
Since you can only log 12 channels at once, you'll have to substitute if you need diff data...
031-2 (Lambda Specified)
054-3 (Accel. Pedal Position %)
114-3 (N75 Duty % Specified)
230-1 (Rail Press Specified)
230-2 (Rail Press Actual)
014-3 (Misfire Sum)
001-2 (Coolant Temp)
The more consistent the logs, the more comparable they'll be for you guys.
As for the logs, might I suggest the following as a general reference...
Use the "Adv. Meas Values" logging function and enabling "Turbo" mode for higher resolution. You can log 12 channels at once using Adv Meas Values.
001-1 (Engine Speed / RPM)
003-2 (MAF)
003-4 (Ignition Angle / Timing Advance)
020-1 (Timing Pull / CF Cyl 1)
020-2 (Timing Pull / CF Cyl 2)
020-3 (Timing Pull / CF Cyl 3)
020-4 (Timing Pull / CF Cyl 4)
031-1 (Lambda [x 14.7 for AFR])
054-4 (Throttle Plate Angle %)
114-4 (N75 Duty Cycle % Actual)
115-3 (Boost Specified)
115-4 (Boost Actual)
I would recommend only doing the runs after engine is to full operating temperature from 2000rpm to redline for the most accurate results. I prefer 3rd gear because its much safer for the street as the speed as you reach redline is lower.
Since you can only log 12 channels at once, you'll have to substitute if you need diff data...
031-2 (Lambda Specified)
054-3 (Accel. Pedal Position %)
114-3 (N75 Duty % Specified)
230-1 (Rail Press Specified)
230-2 (Rail Press Actual)
014-3 (Misfire Sum)
001-2 (Coolant Temp)
The more consistent the logs, the more comparable they'll be for you guys.
Last edited:
John@Unitronic
Go Kart Champion
Rather then other threads leading OT... :thumbsup:
FLtrooper
Go Kart Champion
Sir, an email has been sent! Just took some logs, Perhaps the information is worthy of being graphed.
Thanks for being an assist to the community!
:thumbsup:
Djunited1
Go Kart Champion
mdhollis
Go Kart Champion
I look forward to seeing these.
Your logs look good. I'm not sure you'll see much more boost up top; as it is you're actual is matching requested. You could see more g/s. I'd say the two biggest improvements (measurable by VAGCOM anyway) would be a little less timing pull and lower IATs. You should try and get some IATs logs before you put on the new parts.
Djunited1
Go Kart Champion
i'll be sure to get some more logs before i install.
if my logs look good i'm guessing there is noway i can get anyone to diagnose the 2-3k rpm issue some of us are having in this latest thread?
http://www.golfmk6.com/forums/showthread.php?t=57722
