Are WGDC a good way to see intercooler pressure loss ?

[vadonchez]

Hi guys

I have a question in my head and i would like to have your advice .
my car is a z4 35is .

When i tuned it with MHD V10 stage 1+ one year ago my turbo start to whine at low rpm.

Since this time i'm trying to understand what' the problem and i saw that lot of tuned N54 owner are concerned by this whine.

Recently i changed my turbo set for another OEM one and whine came back after 1000km. Whine came back with MHD V10 stage 2 wich target around 14psi flat up to 6500 rpm.

I will rebuilt my second set with melett CHRA and upgrade compressor wheel for billet one because i bench my first turbo set and my turbo specialist found that both of my CHRA was unbalanced because of "orange peel effect" on my compressor wheel.

I made a video here:

Upgrade comrpessor wheel should help and i now use V10 stage 2 E50 with power slider @95% in order to cut boost above 5900 rpm and it works well as shown trough those logs:

https://datazap.me/u/vadonchez/v10-stage-2-e50-95-et-90?log=2&data=3-5-21

https://datazap.me/u/vadonchez/stage-2v10-e50-95?log=0&data=3-5-21

I do that because of a post on E90 forum wich gave us the limit of our TD03 turbo with 1.5psi of pressure drop:

RPM PSI HP Nm

1300 4.00 55 302
1400 6.50 67 343
1500 15.80 104 493
1600 17.50 117 521
1700 17.60 125 522
1800 17.70 132 524
1900 17.80 140 525
2000 17.80 148 525
2100 17.90 155 527
2200 18.00 163 529
2300 18.10 171 530
2400 18.20 179 532
2500 18.30 187 534
2600 18.40 195 535
2700 18.50 204 537
2800 18.50 211 537
2900 18.60 219 538
3000 18.80 228 542
3100 18.90 237 543
3200 19.00 245 545
3300 19.10 253 546
3400 19.20 262 548
3500 19.30 270 550
3600 19.40 279 551
3700 19.30 286 550
3800 19.20 293 548
3900 19.10 299 546
4000 19.00 306 545
4100 18.90 313 543
4200 18.70 319 540
4300 18.60 325 538
4400 18.50 332 537
4500 18.40 338 535
4600 18.10 343 530
4700 17.70 346 524
4800 17.30 349 517
4900 16.90 352 511
5000 16.50 354 504
5100 16.20 358 500
5200 15.80 360 493
5300 15.50 363 488
5400 15.10 365 482
5500 14.80 368 477
5600 14.50 371 472
5700 14.10 373 466
5800 13.60 373 458
5900 13.00 371 448
6000 12.40 369 438
6100 11.90 368 430
6200 11.30 366 420
6300 10.80 365 412
6400 10.20 362 403
6500 9.70 360 394
6600 9.10 357 385
6700 8.60 354 377
6800 8.20 354 370
6900 7.70 351 362
7000 7.20 348 354



But recently I learned about pressure drop....
My car has a wagner evo1 IC .WAGner website claimed 2.5psi of pressure drop for around 400CFM:

If I trust a guy on E90 forum wich claimed that with 8psi@6500rpm (OEM map) we already have 478CFM of air....
I understood that my IC should have a lot more pressure drop than 2.5psi what coincides with a technical review from MOSSELMAN wich found up to 5PSI of pressure drop with wagenr evo1:

https://streetandcircuit.biz/wp-content/uploads/2016/04/intercooler_test_Mosselman.pdf

when my turbo start to whine my boost above 6000rpm was around 13 psi , if my wagner IC has 4 or 5 psi of pressure drop at this rpm then boost at turbo output should be near 17/18psi wich is a lot more than what they are able to give at this rpm...

What I don't understand is that if my pressure drop is so bad why my wgdc are ok?

Should I go for wagner competition evo 2 wich has only 2.5psi of pressure drop @560CFM??

Thanks for your help!

 

[wheela]

On your wagner graph, you've highlighted the performance curve for the oem intercooler. The pic is a little fuzzy, but evo 1 is one of the higher curves. I have the evo1 also, here's a graph from wagner that may be a little more useful for you, as the flow is in g/sec (same as our logs). You can see from a flow restriction perspective, the evo1 and evo2 are almost identical. So if you're concerned about the flow restriction, I don't think the evo2 will get you a noticable difference over the evo1. May need to move to something bigger.

 

[wheela]

Another thing to consider on Wagner's flow graphs - they list the pressure delta across the intercooler vs. flow, but what pressures are the inlets and outlets at? So for example 2.5 psi at inlet and 0psig at outlet vs. say 20.5 psi inlet and 18psig outlet? If it was done on a flow stand with the outlet at atmospheric pressure, their numbers may not represent what you'd see in a car running boost. As boost raises, the air compresses which increases its density. Since it's denser, velocity will be slower at the same massflow rate. With the same mass flow but higher pressure like when you're in boost, I suspect you'll see less pressure drop than indicated on their graphs, but I'm not sure if it's a meaningful difference or not.

 

[vadonchez]

You're right, i highlighted the wrong one, i modified my graph and add EVO2 COMP CFM .
thats why CFM is more usefull no? To me CFM include boost into the equation but i could be wrong...i imagine that 6000rpm @ 0PSi vs 6000rpm@10psi give not the same CFM result.
If I change my EVO1 that's not for the performance evo2 but for the evo II competition wich is a lot better from what i saw into wagner graphs.

 

[logic vs emotion]

DME is reducing the load because the tune is passing the requested load value. Throttle is is doing it's best to control the boost from over shooting the target. The WG is hardly working @ 42% DC. Is there a reason you're not running the stage 2+ V10 map? I'm not sure about the noise from the turbo. And unless you're using a truck intercooler, pressure drop is the least of your worries. Merry Christmas. ^5

 

[wheela]

Hi guys

I have a question in my head and i would like to have your advice .
my car is a z4 35is .

When i tuned it with MHD V10 stage 1+ one year ago my turbo start to whine at low rpm.

Since this time i'm trying to understand what' the problem and i saw that lot of tuned N54 owner are concerned by this whine.

Recently i changed my turbo set for another OEM one and whine came back after 1000km. Whine came back with MHD V10 stage 2 wich target around 14psi flat up to 6500 rpm.

I will rebuilt my second set with melett CHRA and upgrade compressor wheel for billet one because i bench my first turbo set and my turbo specialist found that both of my CHRA was unbalanced because of "orange peel effect" on my compressor wheel.

I made a video here:

Upgrade comrpessor wheel should help and i now use V10 stage 2 E50 with power slider @95% in order to cut boost above 5900 rpm and it works well as shown trough those logs:

https://datazap.me/u/vadonchez/v10-stage-2-e50-95-et-90?log=2&data=3-5-21

https://datazap.me/u/vadonchez/stage-2v10-e50-95?log=0&data=3-5-21

I do that because of a post on E90 forum wich gave us the limit of our TD03 turbo with 1.5psi of pressure drop:

RPM PSI HP Nm

1300 4.00 55 302
1400 6.50 67 343
1500 15.80 104 493
1600 17.50 117 521
1700 17.60 125 522
1800 17.70 132 524
1900 17.80 140 525
2000 17.80 148 525
2100 17.90 155 527
2200 18.00 163 529
2300 18.10 171 530
2400 18.20 179 532
2500 18.30 187 534
2600 18.40 195 535
2700 18.50 204 537
2800 18.50 211 537
2900 18.60 219 538
3000 18.80 228 542
3100 18.90 237 543
3200 19.00 245 545
3300 19.10 253 546
3400 19.20 262 548
3500 19.30 270 550
3600 19.40 279 551
3700 19.30 286 550
3800 19.20 293 548
3900 19.10 299 546
4000 19.00 306 545
4100 18.90 313 543
4200 18.70 319 540
4300 18.60 325 538
4400 18.50 332 537
4500 18.40 338 535
4600 18.10 343 530
4700 17.70 346 524
4800 17.30 349 517
4900 16.90 352 511
5000 16.50 354 504
5100 16.20 358 500
5200 15.80 360 493
5300 15.50 363 488
5400 15.10 365 482
5500 14.80 368 477
5600 14.50 371 472
5700 14.10 373 466
5800 13.60 373 458
5900 13.00 371 448
6000 12.40 369 438
6100 11.90 368 430
6200 11.30 366 420
6300 10.80 365 412
6400 10.20 362 403
6500 9.70 360 394
6600 9.10 357 385
6700 8.60 354 377
6800 8.20 354 370
6900 7.70 351 362
7000 7.20 348 354



But recently I learned about pressure drop....
My car has a wagner evo1 IC .WAGner website claimed 2.5psi of pressure drop for around 400CFM:

View attachment 87808

If I trust a guy on E90 forum wich claimed that with 8psi@6500rpm (OEM map) we already have 478CFM of air....
I understood that my IC should have a lot more pressure drop than 2.5psi what coincides with a technical review from MOSSELMAN wich found up to 5PSI of pressure drop with wagenr evo1:

https://streetandcircuit.biz/wp-content/uploads/2016/04/intercooler_test_Mosselman.pdf

when my turbo start to whine my boost above 6000rpm was around 13 psi , if my wagner IC has 4 or 5 psi of pressure drop at this rpm then boost at turbo output should be near 17/18psi wich is a lot more than what they are able to give at this rpm...

What I don't understand is that if my pressure drop is so bad why my wgdc are ok?

Should I go for wagner competition evo 2 wich has only 2.5psi of pressure drop @560CFM??

Thanks for your help!

Wow, that mosselman info you linked shows the oem ic with less pressure drop than the wagner EVO 1??? Is that correct? I see it's pretty old data. Wagner's data shows both EVO 1's out flowing the stock IC. WTF

 

[vadonchez]

View attachment 89548
DME is reducing the load because the tune is passing the requested load value. Throttle is is doing it's best to control the boost from over shooting the target. The WG is hardly working @ 42% DC. Is there a reason you're not running the stage 2+ V10 map? I'm not sure about the noise from the turbo. And unless you're using a truck intercooler, pressure drop is the least of your worries. Merry Christmas. ^5

Thanks for reply.
I don't use STAGE 2+ because when i look at our turbo flow map i undestand that this tune makes them work out of efficiency and my turbo are whining @low rpm ....I don't understand why because lot of guys are running MHD map without the whine problem...
I agree that WGDC is low regarding WGDC lot of people are runing on there N54. Without this whine i will run V7 stage 2+ wich i found great!