2.5L WRX Modification Breakdown (with logs and road dynos)

[Bullwinkle]

Below is a comparison from my 06 WRX at each stage of its short life. Below is a list of each set up with a an ECU log and a road dyno comparo from the previous modification level.

All of the raw data can be found here. (https://netfiles.umn.edu/users/wage0052/www/RomRaider/Logs/ModDynoComparo/)

Each stage of modifications below has a full list of the power mods that were on the car when the log and dyno was taken. For continuity, all logs used were as close to 80 degree intake temps as possible. So, the logs aren't all perfect and knock free (yeah, especially the stock one :(), but they represent a good sample pool. All the custom tuning as done by me. I'll breakdown my thoughts on each "stage" after the data.

Stock
Mods:
Panel Filter
Intake silencer delete


RPM Load Timing MRP WG MAFv
2396 1.3 23.5 1.89 15.69 2.78
2414 1.45 18 3.63 16.47 2.88
2524 1.57 14.5 5.37 16.86 3.04
2580 1.69 13.5 6.96 16.86 3.08
2682 1.74 14 7.84 17.65 3.18
2760 1.79 14 8.42 16.86 3.2
2877 1.8 14 8.71 16.47 3.26
2968 1.8 15 8.71 17.65 3.3
3073 1.79 16 8.85 19.61 3.36
3164 1.8 16.5 9 20.78 3.36
3261 1.83 16.5 9.43 23.92 3.44
3394 1.92 16.5 10.3 29.41 3.5
3518 2.03 16 11.17 37.65 3.6
3610 2.12 15.5 11.75 40.39 3.68
3752 2.18 15.5 12.04 40 3.76
3864 2.19 13 12.19 39.22 3.8
3946 2.2 13.5 12.19 38.43 3.8
4120 2.15 14.5 11.75 40 3.8
4230 2.12 16.5 11.46 42.75 3.84
4310 2.13 16.5 11.61 44.31 3.88
4461 2.17 17 11.9 44.71 3.94
4546 2.17 17 11.75 45.1 3.98
4700 2.15 18 11.61 45.49 3.98
4819 2.14 18.5 11.61 46.27 3.98
4896 2.13 18.5 11.46 47.06 4
5040 2.13 18.5 11.32 48.24 4.04
5111 2.13 18.5 11.17 48.63 4.06
5220 2.12 18.5 11.03 51.37 4.08
5316 2.11 19 10.88 53.33 4.1
5456 2.09 19.5 10.74 56.08 4.1
5561 2.08 19.5 10.74 60 4.12
5605 2.06 20 10.59 60.78 4.12
5746 2.04 20.5 10.59 55.69 4.14
5804 2 20.5 10.16 51.37 4.14
5906 1.98 21 10.16 47.45 4.12
5974 1.95 21.5 10.01 43.14 4.14
6104 1.9 22 9.87 41.57 4.12
6130 1.88 22 9.43 38.04 4.12
6201 1.85 22.5 9.29 32.55 4.12
6321 1.82 23 9 30.59 4.12
6321 1.79 23.5 8.71 27.84 4.1
6454 1.76 24 8.42 24.31 4.1


Stage 1
Mods:
Panel Filter
Intake silencer delete

Stock vs Stage 1
https://netfiles.umn.edu/users/wage0052/www/RomRaider/Logs/ModDynoComparo/stockvsstage1.JPG


RPM Load Timing MRP WG MAFv
2203 1.33 20 2.61 77.65 2.7
2302 1.44 18.5 3.92 77.65 2.74
2385 1.55 17 5.22 77.25 2.84
2488 1.67 16.5 6.53 75.69 2.92
2598 1.78 16 8.13 72.94 3.02
2704 1.88 15.5 9.43 70.2 3.16
2811 1.99 15 10.88 67.06 3.26
2938 2.1 15 12.33 63.92 3.38
3085 2.18 14.5 13.49 59.61 3.5
3224 2.21 15 13.93 56.47 3.56
3388 2.21 15 13.93 56.08 3.6
3473 2.24 15.5 13.64 55.29 3.64
3632 2.28 15.5 13.35 54.9 3.7
3746 2.28 16 13.06 54.9 3.76
3924 2.26 16.5 12.91 54.9 3.78
4054 2.25 16.5 12.91 54.9 3.82
4154 2.23 17 12.77 56.47 3.86
4321 2.21 17 12.77 57.65 3.88
4409 2.2 17.5 12.48 58.43 3.9
4561 2.21 17.5 12.48 60.39 3.94
4646 2.21 17.5 12.48 62.75 3.96
4779 2.21 18 12.62 64.31 4
4899 2.19 18 12.48 66.27 4.04
5005 2.19 18 12.33 67.84 4.04
5131 2.18 18.5 12.04 69.8 4.08
5238 2.16 18.5 11.9 71.37 4.1
5386 2.14 19 11.46 79.22 4.1
5441 2.14 19 11.32 83.53 4.12
5578 2.09 19.5 11.03 85.49 4.12
5678 2.05 19.5 10.88 85.88 4.12
5771 2.04 20 10.74 78.82 4.14
5864 1.99 20.5 10.59 76.08 4.14
5942 1.98 20.5 10.59 67.84 4.14
6035 1.95 20.5 10.45 65.1 4.12
6056 1.93 19.5 10.3 58.82 4.14
6182 1.9 20 10.3 54.51 4.14
6256 1.88 21.5 10.16 53.73 4.14
6260 1.85 22 10.01 46.67 4.14
6400 1.82 22.5 9.58 42.35 4.14
6476 1.8 23 9.43 39.22 4.14
6479 1.75 24.5 8.27 4.71 4.14
6588 1.41 28 3.92 0 4.08


Stage 2
Mods:
Panel Filter
Intake silencer delete
Turbo XS stealthback catted exhaust (4" downpipe, 3" catted midpipe)
Stock axleback

Stage 1 vs Stage 2
https://netfiles.umn.edu/users/wage0052/www/RomRaider/Logs/ModDynoComparo/stage1vsstage2.JPG


RPM Load Timing MRP WG MAFg/s
2180 1.42 15 2.76 74.12 54.63
2259 1.58 13.5 4.79 73.73 63.54
2346 1.79 12 7.11 73.73 73.45
2449 2.01 12 9.58 73.33 86.81
2570 2.24 11.5 12.62 72.94 99.68
2678 2.46 10.5 15.38 72.16 114.44
2844 2.62 11 17.27 69.02 127.71
2995 2.65 11 17.7 69.02 132.57
3144 2.65 11 17.7 70.2 140.43
3323 2.68 11.5 17.56 70.2 149.55
3432 2.7 11.5 17.27 70.59 156.13
3583 2.73 12 16.83 70.98 161.67
3749 2.72 12 16.54 70.98 169.82
3873 2.69 12 16.11 71.37 172.85
4021 2.67 12.5 15.96 71.37 175.59
4132 2.61 13 15.67 72.55 180.04
4311 2.57 14 15.53 74.51 186.52
4408 2.56 14.5 15.09 75.29 187.25
4509 2.53 14.5 14.8 76.47 191.36
4615 2.49 15.5 14.51 78.04 193
4786 2.46 17 14.22 79.61 195.06
4855 2.43 17.5 13.93 80.39 196.71
5006 2.41 17.5 13.35 81.96 199.17
5131 2.35 18 13.06 82.75 199.99
5176 2.33 19 12.62 83.53 204.61
5326 2.29 19 12.19 84.31 204.2
5433 2.27 20 11.9 85.49 203.83
5518 2.25 19 11.75 85.88 204.28
5572 2.2 21 11.32 85.1 206.06
5694 2.17 21 11.03 81.96 205.61
5740 2.13 21.5 10.88 80.39 205.61
5830 2.11 22 10.59 75.29 204.72
5885 2.08 22 10.59 72.55 206.5
5963 2.06 22 10.45 67.45 204.28
6076 2.03 21 10.3 65.88 202.61
6102 2.01 21 10.16 63.53 205.61
6160 2 21.5 10.01 60.39 206.06
6212 1.97 21.5 10.01 55.29 206.06


Stage 2+
Mods:
Panel Filter
Intake silencer delete
Turbo XS stealthback catted exhaust (4" downpipe, 3" catted midpipe)
Maddad Whisper 2.5" axleback
GMBCS

Stage 2 vs Stage 2+
https://netfiles.umn.edu/users/wage0052/www/RomRaider/Logs/ModDynoComparo/stage2vsstage2%2B.JPG


RPM Load Timing MRP WG MAFv
2138 0.3 29 -8.56 0 2.2
2183 1.06 25 -0.44 9.8 2.66
2173 1.34 16.5 1.74 34.12 2.8
2266 1.56 14.5 3.92 76.86 2.9
2370 1.8 13.5 6.53 76.86 3.14
2460 2.12 12 10.3 76.86 3.36
2595 2.46 11.5 14.22 75.29 3.58
2728 2.84 11 18.14 73.33 3.72
2930 3 11.5 19.3 72.55 3.84
3088 3.03 11.5 19.15 72.55 3.9
3218 3.04 11.5 19.01 72.94 3.96
3388 3.03 12 18.57 73.73 3.98
3560 3.06 12 18.28 74.9 4.06
3692 3.07 12.5 18.14 75.29 4.12
3876 3.05 13 17.85 76.08 4.14
4044 3 13.5 17.56 76.86 4.16
4152 2.93 14 17.27 77.65 4.18
4272 2.87 14.5 16.69 79.22 4.2
4451 2.83 15.5 15.96 80.39 4.2
4576 2.76 16 15.53 81.57 4.2
4708 2.72 16.5 15.09 82.35 4.24
4843 2.65 17 14.51 83.53 4.24
4915 2.61 17.5 13.78 84.31 4.24
5025 2.55 18 13.35 85.1 4.24
5186 2.5 19 12.77 85.88 4.24
5255 2.46 19 12.33 87.06 4.26
5389 2.42 20 12.04 87.84 4.26
5444 2.37 20 11.61 89.02 4.26
5526 2.34 20.5 11.17 89.41 4.26
5684 2.31 21 11.03 89.02 4.26
5754 2.26 21.5 10.74 88.63 4.26
5812 2.24 21.5 10.59 88.24 4.26
5880 2.21 21.5 10.45 88.24 4.26
5952 2.18 22 10.3 87.84 4.26
6027 2.15 22 10.16 87.84 4.26
6156 2.11 22.5 9.87 87.45 4.26
6184 2.09 22.5 9.87 87.45 4.26
6240 2.08 22.5 9.87 87.06 4.26
6313 2.05 23 9.58 87.06 4.26
6380 2.04 23 9.58 86.67 4.26
6494 2.01 23.5 9.43 86.67 4.26


TD05 18g 7cm
Mods:
Panel Filter
Intake silencer delete
Turbo XS stealthback catted exhaust (4" downpipe, 3" catted midpipe)
Maddad Whisper 2.5" axleback
GMBCS
FP TD05 18g 7cm Turbo

Stage 2+ vs 18g
https://netfiles.umn.edu/users/wage0052/www/RomRaider/Logs/ModDynoComparo/stage2%2Bvs18g.JPG


RPM LOAD TIMING MRP MAFgs WB02
2012 1.2 23.5 0.58 41.15 12.33
2058 1.23 23 0.87 42.66 13.23
2078 1.26 23 1.31 43.93 10.67
2137 1.28 23.5 1.74 46.2 11.79
2172 1.33 23.5 2.32 49.2 12.14
2223 1.36 24 2.76 51.37 12.22
2248 1.39 24.5 3.19 53.15 12.25
2290 1.43 24 3.48 56.3 12.79
2332 1.46 24 3.92 58.77 12.67
2396 1.52 24.5 4.5 62.1 12.73
2408 1.55 23.5 4.93 65.33 13.26
2490 1.64 23 5.51 69.55 13.29
2517 1.68 22 6.09 73.99 13.41
2568 1.75 21 6.82 75.95 13.19
2637 1.8 20.5 7.4 81.25 13.19
2688 1.88 19.5 8.13 86.85 13.32
2777 1.94 18.5 9.14 93.7 13.41
2820 2.05 17.5 10.16 101.8 13.22
2922 2.13 16.5 11.46 107.22 13.69
2993 2.29 15 12.91 117.22 13.74
3052 2.41 13.5 14.51 128.99 13.22
3135 2.61 12.5 16.11 141.06 11.91
3215 2.76 11.5 17.85 152.34 11.8
3312 2.96 11 19.73 170.95 11.69
3443 3.09 11 20.89 181.37 11.44
3584 3.21 11.5 21.18 192.18 11.33
3675 3.25 11.5 21.62 201.02 11.3
3830 3.24 11.5 21.18 200.54 11.14
3849 3.21 12 21.18 208.29 11.11
3934 3.22 12 21.47 210.96 11.07
4000 3.22 12 21.47 210.51 11.04
4081 3.14 12 20.89 214.07 10.97
4172 3.14 12 20.89 217.19 11.1
4249 3.14 12 21.04 224.01 11.05
4384 3.15 12 20.89 229.68 11.25
4471 3.16 12 20.6 232.57 11.26
4546 3.13 12.5 20.6 238.34 11.11
4639 3.12 12.5 20.6 239.78 11.01
4684 3.09 12.5 20.46 241.23 11.01
4798 3.09 12.5 20.6 249.08 11.02
4902 3.1 12.5 20.46 250.61 11.1
5005 3.09 12.5 20.31 255.73 11.22
5044 3.06 13 20.17 257.78 11.19
5188 3.05 13 19.88 261.37 11.05
5258 3.03 13 19.59 262.93 11.16
5296 3 13 19.44 266.67 11.13
5363 2.99 13 19.44 266.13 11.16
5488 2.99 13 19.44 270.97 11.11
5510 2.95 12 19.3 270.97 11.2
5591 2.92 12 19.15 273.65 10.95
5652 2.91 12 19.15 274.73 10.95
5737 2.88 12.5 18.86 274.19 11.13
5815 2.83 13 18.57 275.27 10.98
5874 2.82 13 18.43 276.34 11
5935 2.77 13.5 18.43 274.73 11.02
6003 2.75 14 17.99 275.27 11.05
6121 2.71 14.5 17.85 274.19 10.98
6117 2.7 13.5 17.56 272.04 11.1
6238 2.64 14 17.56 273.12 11.02
6301 2.64 14.5 17.41 273.12 11.08
6354 2.61 14.5 17.27 273.12 10.82
6399 2.59 15 17.12 273.12 10.95
6464 2.56 15.5 16.83 274.19 10.94
6534 2.55 16.5 16.83 273.12 10.78
6527 2.52 16.5 16.69 272.04 10.8
6635 2.51 17 16.54 274.73 10.73
6620 2.48 18.5 16.4 273.12 11.02
6670 2.46 19 16.25 275.27 11.05
6784 2.43 19 16.25 272.04 10.76
6763 2.42 19 16.11 276.34 10.64
6878 2.39 19.5 16.11 273.12 10.92
6929 2.37 20 16.11 273.12 10.89

[Bullwinkle]

Breakdown
The stock tune sucks! Boost is basically a linear curve, and then dies off up top. This terrible curve is compounded by the weird scissor timing and lean AF ratios from the open loop-closed loop delay, and creates a car that really surges when you mash on the pedal.

Second, the stock WRX axleback is terrible. While I gained some midrange torque after tossing on the downpipe for stage 2, the car was still extremely bottled up top. After putting on a high flow axleback and a GMBCS, the car really opened up. In addition, the extra boost in the midrange really added a fun punch down low.

Third, we all know the TD04 is insanely small for the 2.5L. The turbo is really snappy and fun while daily driving on the street, but dies reeealy quickly. For those of you with a 2.0L WRX, this is a little different. While the 06+ WRX has trouble holding 10 PSI at redline, the 2.0L WRX's can hold around 14 PSI, and are often just injector limited on a stage 2 tune.

Last, the 18g is OK for the 2.5L engine. It's a small turbo, and performs similar to a VF39, with slightly more top-end, even in the 7cm trim. As you can see, it has a ton more top end then the TD04. I am really enjoying this turbo, as it flattened out the powerband, and I am now actually able to drive above 5k RPM.

Hope you learned something, or at least found it interesting. :)

[Justin]

nate, you still using our prototype bcs?

[Bullwinkle]

Yup, it's working good. That 18g log is from when I had the GMBCS on, though. All my ones with yours on there are in much colder weather.

I'm liking it, it's quieter. :)

[Soupboy]

Thanks Nate. This is a great post for comparing common mod "paths" on a relative basis. I think you found 5 more HP than my tune just to annoy me!

[Bullwinkle]

Also, I guess I should include this:

Regarding the logs, here are the parameters logged and what they mean:

RPM - This is an easy one
Load - Engine load, a number calculated based on RPM and airflow, roughly equivalent to torque
Timing - Engine timing, in degrees below top dead center
MRP - Manifold Relative Pressure (this is boost)
WG - Wastegate Duty Cycles (this controls boost, the higher number, the more boost)
MAF - Mass Air Flow - I've logged in a couple different versions (sorry, my method of logging has changed :)), MAFv is the voltage past the MAF sensor, MAF g/s is a caclulated grams per second value based on this voltage. This value can be roughly equated to HP.

[Ryan]

nice breakdown. I think this will give some people some ideas of what to do when they ask "What mod should I do?"

[Ronnie@RSmotors]

I see some inconsistency on the log around 6k. Where the timing would drops a little and go back up. I know that would show on the dyno graph but it doesn't seem to show it on your graph. This is the part where I would sacrifice a little power to get a smoother graph or up the timing in that area and hope it takes it. Only the first and second to last didn't have any and pretty smooth timing curve.

[Dream]

Awesome post Nate, thanks for the info. And the GMBCS is silent, if you mount it in the right spot. ;)

[Shibbs]

Yes, I just moved mine and it is silent now.

Especially silent, being as the car has been sitting for over 2 weeks now. lol

[Bullwinkle]

I see some inconsistency on the log around 6k. Where the timing would drops a little and go back up. I know that would show on the dyno graph but it doesn't seem to show it on your graph. This is the part where I would sacrifice a little power to get a smoother graph or up the timing in that area and hope it takes it. Only the first and second to last didn't have any and pretty smooth timing curve.

Yeah, some of the logs have some learned timing pulls and/or slight knock as I was attempting to get logs all right in the same IAT range for numerical comparison, and not just the best ones.

On my car, I change my negative feedback correction timing retard number to half of the stock value, so any single knock events will not make a huge impact on the road dyno.

[Bullwinkle]

Also, Ronnie, would you be willing to share some logs of similar cars and modifications from your dyno tuning experience? Personally, I would be very interested to see if the dyno loads differently, if limited airflow through an IC makes a difference, or if there are any other quirk differences.

[Bullwinkle]

Here's some more info from logging the 18g today. Cold air is quite fun and makes absolutely ridiculous dyno numbers :).


RPM Timing Throt Load IDC IAT MRP MAF WGDC
2230 25 100 1.34 15.74 52 1.85 50.06 87.06
2315 24 100 1.44 17.32 52 3.04 56.77 87.06
2452 21.5 100 1.62 19.97 52 4.54 66.64 86.67
2582 20.5 100 1.78 23.24 50 6.34 77.19 84.31
2736 18.5 100 1.99 27.55 50 8.85 93.5 82.35
2922 15 100 2.29 35.7 50 12.19 116.67 74.9
3102 11 100 2.87 48.85 50 16.76 149.32 64.71
3337 10 100 3.38 65.1 50 21.53 194.24 60
3676 11 100 3.51 72.34 50 22.43 215.86 59.61
3899 11 100 3.44 72.03 50 22.02 220.79 59.22
4083 11 100 3.39 75.81 50 21.96 229.68 58.82
4308 11 100 3.39 80 50 21.81 245.07 59.61
4529 12 100 3.35 82.24 50 21.47 251.64 59.22
4743 12 100 3.3 84.33 50 20.95 261.88 59.61
4986 12.5 100 3.25 87.52 50 20.55 268.82 59.61
5151 13 100 3.17 88.16 50 19.78 273.65 60
5388 13 100 3.12 91.16 52 19.47 278.49 60
5529 13.5 100 3.05 91.92 52 18.87 279.57 59.22
5744 13.5 100 2.94 90.35 52 18.55 281.78 56.86
5853 14 100 2.88 92.38 52 18.1 280.66 53.73
6078 14.5 100 2.79 91.62 52 17.16 280.68 52.16
6226 15.5 100 2.7 91.07 52 16.63 278.49 50.59
6314 16 100 2.64 92.56 50 16.14 278.49 49.41
6515 17 100 2.59 93.18 52 15.92 280.66 49.02
6648 18.5 100 2.53 92.46 50 15.63 277.96 49.8


Excel Dyno, numbers compared to 70 degree weather, car weight normalized:
https://netfiles.umn.edu/users/wage0052/www/RomRaider/Logs/ModDynoComparo/1-31Roaddynotempcomparo.JPG

[idget]

Cold air is quite fun and makes absolutely ridiculous dyno numbers :).


Juuuuust a little bit :biggrin:

Max load compared to stock is hilarious... happens earlier too.

[Bullwinkle]

I was meaning to, but forgot to post this comparison.

Lots of people discuss the difference between the different 18g turbos. This is a dyno comparison of my TD05 18g 7cm to an TD05 18g 8cm that I tuned last fall. I attempted to normalize for different intake temps.

https://netfiles.umn.edu/users/wage0052/www/RomRaider/dynos/tv06wrxvsbwdyno.JPG

[Tdagen]

Cool thread...

[bobafett04wrx]

I wish I had a 2.5l