Request: need for DIY Tuning How-To article

[Red94Chev]

Would any of the experienced tuners (Fast305, HaulnA$$ + others) consider doing a DIY tuning article for this section? Yes, I know there is a lot of tuning articles at TGO, but they are all over the place and poorly organized. I'm also not sure how much of the discussion for different bins for camaro/firebirds running TPI applies to TBI setups. Wouldn't it be nice if it was all in one post as a sticky, or in a downloadable Word doc?

Plus, there is no operating manual for TunerPro RT, yet it is a commonly used tuning program used for $OD tuning. I think the need is there. I've noticed more and more FSC members starting to do their own tunes, including myself. One of the daunting reasons I think most people are hesitant to start DIY tuning is the steep learning curve. An informed and well-structured tuning guide would be a HUGE asset to the performance enthusiasts here. I would attempt it, but I certainly don't have the experience needed for a quality write-up. Any ideas or comments?

[titchener]

The "stickies" and faqs in these forums-

http://www.thirdgen.org/techboard/diy-prom/

http://www.thirdgen.org/techboard/tpi/

http://www.thirdgen.org/techboard/tbi/

are a pretty good introduction to DIY chip tuning and they cover both TBI and TPI pretty well, although there is a lot of info to sift through and absorb. I tried to stay out of it as I knew I would dump too much time into it that I don't really have, but I couldn't resist. I've only done a little chip tweaking so far but now I'm geared up to do a major re-tune with my ECM that has been modified with the EBL Flash system from http://www.dynamicefi.com/ .

I've probably put in well over 100 hours in just trying to get up to speed on this stuff, mostly enjoyable but like I said, time I really didn't have to spend, but oh well.

There are a lot of sharp guys on both this forum and the forums above to help you when you get stuck, so that makes it easier.

Paul T.

[Domino68]

Would any of the experienced tuners (Fast305, HaulnA$$ + others) consider doing a DIY tuning article for this section? Yes, I know there is a lot of tuning articles at TGO, but they are all over the place and poorly organized. I'm also not sure how much of the discussion for different bins for camaro/firebirds running TPI applies to TBI setups. Wouldn't it be nice if it was all in one post as a sticky, or in a downloadable Word doc?

Plus, there is no operating manual for TunerPro RT, yet it is a commonly used tuning program used for $OD tuning. I think the need is there. I've noticed more and more FSC members starting to do their own tunes, including myself. One of the daunting reasons I think most people are hesitant to start DIY tuning is the steep learning curve. An informed and well-structured tuning guide would be a HUGE asset to the performance enthusiasts here. I would attempt it, but I certainly don't have the experience needed for a quality write-up. Any ideas or comments?
Fantastic suggestion! I have been researching DIY chip tuning for a while and there is TONS of info to digest from MANY different places. Even though ThirdGen is a great place to start, I would have to agree that the information is scattered. I am right at the point of purchasing an EBL myself and taking the plunge into more advanced tuning since I am comfortable with making minor changes. A guide that is specifically for our TBI TRUCKS would be a great help for all of us noobz wanting to get started.

[1BadZ71Tahoe]

Fantastic suggestion! I have been researching DIY chip tuning for a while and there is TONS of info to digest from MANY different places. Even though ThirdGen is a great place to start, I would have to agree that the information is scattered. I am right at the point of purchasing an EBL myself and taking the plunge into more advanced tuning since I am comfortable with making minor changes. A guide that is specifically for our TBI TRUCKS would be a great help for all of us noobz wanting to get started.

TTT, Chime in Experts! :cool:

[93V8S10]

Would any of the experienced tuners (Fast305, HaulnA$$ + others) consider doing a DIY tuning article for this section? Yes, I know there is a lot of tuning articles at TGO, but they are all over the place and poorly organized. I'm also not sure how much of the discussion for different bins for camaro/firebirds running TPI applies to TBI setups. Wouldn't it be nice if it was all in one post as a sticky, or in a down loadable Word doc?

Plus, there is no operating manual for TunerPro RT, yet it is a commonly used tuning program used for $OD tuning. I think the need is there. I've noticed more and more FSC members starting to do their own tunes, including myself. One of the daunting reasons I think most people are hesitant to start DIY tuning is the steep learning curve. An informed and well-structured tuning guide would be a HUGE asset to the performance enthusiasts here. I would attempt it, but I certainly don't have the experience needed for a quality write-up. Any ideas or comments?
IMO a tuning manual for the $0D is a great ideal. When I first starting tuning it would have been very helpful, and would still be very helpful.
But does anybody have the time, energy, knowledge, and desire to wright it?:dunno:

[Fast305]

IMO a tuning manual for the $0D is a great ideal. When I first starting tuning it would have been very helpful, and would still be very helpful.
But does anybody have the time, energy, knowledge, and desire to wright it?:dunno:

I've got the energy, drive, and knowledge to write one, but I am lacking the time to.

[91chevZ71]

What happened to Haulin'???

We definitely need a big tuning article. don't forget $42, in addition to $0D/$31

[Fast305]

What happened to Haulin'???

We definitely need a big tuning article. don't forget $42, in addition to $0D/$31

$42, $61, $62, $63, $85, $OE, $OD, $31, $4E, $4F, are all TBI masks. Then some of the older 60*V6 engines in the S10s and FWD minivans used some other ECMs and MASKs.

[1BadZ71Tahoe]

$42, $61, $62, $63, $85, $OE, $OD, $31, $4E, $4F, are all TBI masks. Then some of the older 60*V6 engines in the S10s and FWD minivans used some other ECMs and MASKs.

Fast,

What can I do to tickle your fancy on MAKING some time?

How about a list of definitions of all Constants/Tables ETC. for the 7427 $0D w/ MAF, I already have them a good halfway done i'd say (im probably not right on all of it . . . . .)

Constants
1. Mask ID byte: 0x0D = ID for Bin’s Mask ($0D Mask)
2. Stoich AFR: 14.10 AFR = Stoichiometric Value (Neither adding nor subtracting fuel)
3. %DC threshold to flag AE as active: 1.95 %DC =
4. Post DFCO AE pulse: 1.53 msec = DFCO is as you mentioned, long coast-downs.
5. Time for INT to remain locked after AE: 1.25 secs =
6. Time threshold to enable open loop idle: 255.00 secs =
7. Accel Enrich TPS filtering coeff: 190.00 Coeff =
8. DRP threshold to transition from crank to run: 54.53 msec =
9. Base spark advance: 9.83 Deg SA =
10. Main SA bias: 0.00 Deg SA =
11. Cool temp corr. SA bias (change in table conversion as well): 20.01 Deg SA =
12. Ramping rate for SA during crank to run: 0.63 %/msec =
13. AFPR injector constant vacuum filter coeff: 255.00 coeff. =
14. Upper cool temp to bypass PE delay: -40.00 Deg C. = PE (Power Enrichment) Delay = Switches into Open Loop without going into PE (Power Enrichment), when under load the timing is altered to help keep the idle speed consistent).
15. MAP threshold to enter mand. Async: 55.06 kPa =
16. MAP threshold to exit mand. Async: 50.05 kPa =
17. RPM theshold to enter mand.async: 6375.00 =
18. RPM theshold to exit mand.async: 6375.00 =
19. Lower cool temp to bypass PE delay: 150.23 Deg C = PE (Power Enrichment) Delay = Switches into Open Loop without going into PE (Power Enrichment), when under load the timing is altered to help keep the idle speed consistent).
20. Upper cool temp threshold to allow PE AFR adjustment: -40.00 Deg C =
21. Fuel cut-off entry threshold: 5500.00 RPM = RPM the Fuel is cut off.
22. Fuel cut-off exit threshold: 5000.00 RPM = RPM the Fuel is resumed.
23. Error 17, MAF sig. lost time threshold: 1250.00 msecs = Milliseconds before MAF reported lost time
24. Error 17, MAF sig. lost freq. threshold: 100.00 Hz = Milliseconds before MAF reports lose frequency
25. Error 23, MAT low A/D threshold: 4.00 Inverse A/D counts =
26. Error 23, MAT low time threshold to set error: 1.00 Secs =
27. Error 23, MAT low engine time threshold for diags.: 180.00 Secs =
28. Error 25, MAT high A/D threshold: 238.00 Inverse A/D counts =
29. Error 25, MAT high time threshold to set error: 1.00 Secs =
30. Error 23/25 upper MPH limit for diags.: 35.00 MPH =
31. Default MAT value if error: 78.00 Inverse A/D counts =
32. Error 26, manfold temp high threshold: 17.00 A/D counts = Starting Point
33. Error 27, manfold temp low threshold: 251.00 A/D counts = Starting Point
34. MPH threshold for high speed cool fan op.: 40.00 MPH = Starting Point
35. MPH threshold to transition back to low speed cool fan op.: .00 MPH = 0 is Instant Change
36. Low speed fan on threshold: 100.25 Deg C = LOW Temperature in Celsius Starting Point
37. Low speed fan off threshold: 94.28 Deg C = LOW Temperature in Celsius Ending Point
38. High speed fan on threshold: 104.72 Deg C = HIGH Temperature in Celsius Starting Point
39. High speed fan off threshold: 98.76 Deg C = HIGH Temperature in Celsius Ending Point
40. Min temp for closed loop: 45.04 =
41. Upper temp threshold for cold closed loop delay: 48.32 Deg C. =
42. Lower temp threshold for hot restart closed loop delay: 111.44 Deg C. =
43. Min time for closed loop (cold engine): 300.00 Secs =
44. Min time for closed loop (cool engine): 180.00 Secs =
45. Min time for closed loop (hot restart): 30.00 Secs =

o2 Constants?
- The O2 constants are the voltage levels the ecm has to cross when swinging for the PID to work.

The code goes for averaging an AFR, not running AT a specific AFR.

For the engine to run AT a given AFR, means running Open Loop.

It was a delicate balance of changing commanded AFR and O2 voltages to truely arrive at a different commanded AFR.


"Fast O2 Rich/Lean Threshold at Idle" is the median voltage that the ECM will try to obtain via the oxygen sensor.

"Upper Zero Error Ref Slow O2 R/L at Idle" is the upper boundary of the median voltage, and "Lower Zero Error Ref Slow O2 R/L at Idle" is the lower boundary. Think of these as "error margins" for the ECM. As long as the oxygen sensor stays within the upper/lower boundaries, everything's cool -- but it's trying to aim for the rich/lean threshold.

As for "Fast O2 R/L Hysteresis Threshhold at Idle," I can't comment on that one -- it's nowhere in the $6E hack. "Hysteresis" refers to the lag between making a change and the result of that change. If I had to wager a guess, I'd say it has something to do with the amount of time the ECM stays at a certain O2 voltage before adjusting the fuel to
produce a change.

46. Idle mean R/L O2 threshold: 481.74 =
47. Idle lean O2 threshold: 481.74 =
48. Idle rich O2 threshold: 481.74 =
49. Idle O2 proportional gain if rich (unstable idle): 0.031 Gain =
50. Idle O2 proportional gain if lean (unstable idle): 0.039 Gain =
51. Idle O2 proportional gain if rich (stable idle): 0.039 Gain =
52. Idle O2 proportional gain if lean (stable idle): 0.047 Gain =
53. Upper allowed limit for stored BLMs: 128.00 BLM =
54. Lower allowed limit for stored BLMs: 128.00 BLM =
55. Lower transient RPM ratio for derivative fuel: 0.91 RPM ratio =
56. Upper transient RPM ratio for derivative fuel: 1.10 RPM ratio =
57. IAC T/F multiplier for reducing action (cool engine temps): 14.84 % reduction =
58. Time after throttle closed to limit T/F action: 4.00 Seconds =
59. IAC T/F multiplier for reduction action (warm engine temps): 14.06 % reduction =
60. Upper allowed difference b/w steady state and idle integral (D, no A/C): 19.92 =
61. Upper allowed difference b/w steady state and idle integral (D, A/C): 19.92 =

Flags
1. MAT in use: Set =
2. Manifold plenum temp sensor in use: Set =
3. Look up AFR when in closed loop: Not Set =
4. Allow knock prevention: Set =
5. Error 13, O2 sensor error: Set =
6. Error 14, high cool temp: Set =
7. Error 15, low cool temp: Set =
8. Error 16, 2002 PPM VSS failure: Set =
9. Error 17, MAF signal lost: Set =
10. Error 21, high TPS: Set =
11. Error 22, TPS low: Set =
12. Error 23, MAT low: Set =
13. Error 25, MAT high: Set =
14. Error 26, manifold temp high: Set =
15. Error 27, manifold temp low: Set =
16. Error 33, MAP high: Set =
17. Error 34, MAP low: Set =
18. Error 35, IAC failure: Set =
19. Error 42, EST failure: Set =
20. Error 43, ESC failure: Set =
21. Error 44, O2 lean: Set = Oxygen Sensor A/F Ratio is Lean
22. Error 45, O2 rich: Set = Oxygen Sensor A/F Ratio is Rich
23. Error 51, EPROM checksum fail: Set = Check EPROM's Checksum for errors in data
24. Error 54, fuel pump relay failure: Set = Check fuel pump relay; is faulty


------------------------------
Tables
------------------------------

1. ALDL scan tool xmission address table =

Serial byte # Addr.
(null)
63 855
62 275
61 870
60 86D
59 862
58 3270
57 326F
56 22F
55 26B
54 26A
53 26D
52 000
51 298
50 2BC
49 232
48 1D8
47 1D7
46 3214
45 3213
44 053
43 052
42 197
41 857
40 30F9
39 30F8
38 051
37 06D
36 320A
35 3209
34 1ED
33 243
32 242
31 2A7
30 085
29 03E
28 041
27 316
26 046
25 04D
24 050
23 04F
22 044
21 03B
20 03D
19 0AE
18 82E
17 0A0
16 062
15 0A2
14 037
13 00A
12 009
11 008
10 00F
9 00E
8 00D
7 00C
6 00B
5 007
4 036
3 004
2 1D6
1 1D5


2. WB AFR vs A/D volts =

V AFR
(null)
5.00 20.00
4.69 19.40
4.38 18.70
4.06 18.10
3.75 17.50
3.44 16.90
3.13 16.30
2.81 15.60
2.50 15.00
2.19 14.40
1.88 13.70
1.56 13.10
1.25 12.50
.938 11.90
.625 11.30
.313 10.60
000 10.00


3. MAF flow vs. frequency = 85 line table of airflow vs. frequency. Computer takes the average grams per second airflow over one complete intake cycle and calculates the mass of air in that one cylinder, and using the desired AFR, it calculates the pulsewidth for the injectors for the next cylinder.

Hz gms/sec
(null)
12000 459.20
11875 459.20
11750 459.20
11625 459.20
11500 459.20
11375 459.20
11250 459.20
11125 459.20
11000 423.36
10875 406.76
10750 390.95
10625 375.91
10500 361.56
10375 347.88
10250 334.88
10125 322.31
10000 310.34
9875 298.88
9750 287.86
9625 277.27
9500 267.08
9375 257.26
9250 247.77
9125 238.61
9000 229.75
8875 221.15
8750 212.82
8625 204.73
8500 196.82
8375 189.15
8250 181.72
8125 174.53
8000 167.59
7875 160.87
7750 154.38
7625 148.15
7500 142.12
7375 136.28
7250 130.65
7125 125.20
7000 119.93
6875 114.83
6750 109.91
6625 105.16
6500 100.58
6375 95.53
6250 90.66
6125 85.93
6000 80.89
5875 76.21
5750 72.20
5625 67.88
5500 63.62
5375 59.38
5250 55.71
5125 51.44
5000 47.63
4875 43.97
4750 40.95
4625 37.78
4500 35.09
4375 31.80
4250 28.88
4125 26.57
4000 24.48
3875 22.71
3750 20.43
3625 18.83
3500 17.32
3375 15.89
3250 14.54
3125 13.28
3000 12.10
2875 11.01
2750 10.00
2625 9.08
2500 8.23
2375 7.59
2250 7.05
2125 6.28
2000 5.63
1875 5.30
1750 4.24
1625 4.24
1500 8.00


4. Mean rich/lean threshold vs. scaled airflow =

Airflow counts mV
(null)
128 451.36
112 451.36
96 451.36
80 451.36
64 451.36
48 451.36
32 481.74
16 481.74
0 481.74


5. Rich O2 threshold vs. scaled airflow =

Airflow counts mV
(null)
128 451.36
112 451.36
96 451.36
80 451.36
64 451.36
48 451.36
32 481.74
16 481.74
0 481.74


6. Lean threshold vs. scaled airflow =

Airflow counts mV
(null)
128 451.36
112 451.36
96 451.36
80 451.36
64 451.36
48 451.36
32 481.74
16 481.74
0 481.74


7. Proportional O2 flow gain vs. MAP and RPMs =

RPM kPa
20 30 40 50 60 70 80 90 100
3600 0.35 0.35 0.35 0.35 0.35 0.35 0.35 0.35 0.35
3200 0.35 0.35 0.35 0.35 0.35 0.35 0.35 0.35 0.35
2800 0.35 0.35 0.35 0.35 0.35 0.35 0.35 0.35 0.35
2400 0.17 0.35 0.35 0.35 0.35 0.35 0.35 0.35 0.35
2000 0.10 0.35 0.35 0.35 0.35 0.35 0.35 0.35 0.35
1600 0.05 0.17 0.35 0.35 0.35 0.35 0.35 0.35 0.35
1200 0.04 0.17 0.35 0.35 0.35 0.35 0.35 0.35 0.35
800 0.03 0.15 0.27 0.35 0.35 0.35 0.35 0.35 0.35
400 0.03 0.13 0.17 0.35 0.35 0.35 0.35 0.35 0.35


8. Crank PW vs cool temp = If Im not mistaken, its also used in the $0D while in crank to control the crank PW and transitioning AFR. In that, though, a status bit causes the cam sensor stuff to be skipped. One thing I wonder is what generates the interrupts to make it work. Is it maybe the crank signal and DRPs that do it?

[1BadZ71Tahoe]

Deg C Usec
(null)
152 6.26
140 6.74
128 7.22
116 7.70
104 9.14
92 11.07
80 13.48
68 16.84
56 20.69
44 26.47
32 32.73
20 40.91
8 50.05
-4 59.20
-16 70.27
-28 80.85
-40 91.44


9. Crank fuel delay vs. cool temp =

Deg C DRPs
(null)
152 2.00
140 2.00
128 2.00
116 2.00
104 2.00
92 2.00
80 2.00
68 2.00
56 2.00
44 2.00
32 2.00
20 2.00
8 2.00
-4 2.00
-16 2.00
-28 2.00
-40 2.00


10. Restart crank PW multiplier vs. DRPs =
DRPs= The DRP is the inverse of RPM. For a V8 it is:

DRP = 983040 / RPM

So 2625 RPM is 374 DRP

The airflow is gms/sec * 256, for 23637:

gms/sec = 92.3 = 23637 / 256

For a scalar IIRC ARAP uses 80, so we'll try that. Using the equation from above:

LV8 = (((DRP * gms/sec) / 256) * Scalar) / 64


LV8 = (((374 * 92.3) / 256) * 80) / 64

is: 169 for LV8

DRPs Mult.
(null)
24 0.50
23 0.45
22 0.39
21 0.34
20 0.30
19 0.30
18 0.30
17 0.30
16 0.30
15 0.30
14 0.30
13 0.30
12 0.30
11 0.30
10 0.32
9 0.33
8 0.34
7 0.41
6 0.44
5 0.47
4 0.65
3 0.95
2 1.33
1 1.33


11. Hot restart crank PW multiplier vs. DRPs’ =

DRPs Mult.
(null)
24 0.40
23 0.39
22 0.38
21 0.36
20 0.34
19 0.34
18 0.32
17 0.31
16 0.30
15 0.30
14 0.30
13 0.30
12 0.30
11 0.30
10 0.30
9 0.30
8 0.30
7 0.31
6 0.35
5 0.39
4 0.47
3 0.55
2 1.00
1 1.00


12. Choke AFR vs. cool temp = the numbers in this table are subtracted from the "open loop AFR V.s coolant Vs. map" table to richen fuel when first started

AFR
(null)
152 2.00
140 2.00
128 2.00
116 2.00
104 2.00
92 2.00
80 2.00
68 2.50
56 3.00
44 3.00
32 3.00
20 3.50
8 3.70
-4 4.50
-16 5.00
-28 5.50
-40 6.00

Volumetric Efficiency

13. Idle VE (Volumetric Efficiency) (used when MAF errors present) =

RPM kPa
20 25 30 35 40 50 60 70 80 90 100
1800 59.04 76.25 80.16 80.94 82.11 85.63 87.19 88.76 91.10 90.32 88.76
1600 57.09 75.07 78.98 80.55 80.94 85.24 85.63 87.58 89.93 89.54 86.80
1400 53.96 69.21 77.03 78.20 78.59 82.11 83.67 85.24 87.19 88.37 85.24
1200 50.05 64.91 76.25 77.03 77.42 79.37 81.72 82.89 84.85 87.58 83.67
1000 44.97 57.87 69.21 70.38 69.99 72.34 77.81 79.37 81.33 84.85 82.89
800 41.06 49.66 61.00 64.52 65.69 67.25 73.90 76.25 78.20 82.11 82.11
600 37.15 44.97 53.57 58.26 59.82 64.91 68.42 72.34 72.73 76.25 80.16
400 33.23 44.18 50.05 51.61 52.79 61.00 62.95 65.30 67.64 70.38 78.20


14. Open throttle VE (Volumetric Efficiency) (used when MAF errors present) =

kPa
20 25 30 35 40 50 06 70 80 90 100
6400 48.88 64.91 74.29 75.07 75.46 80.16 82.11 87.98 89.93 92.28 92.28
6000 48.88 64.91 74.29 75.07 75.46 80.16 82.11 87.98 89.93 92.28 92.28
5600 48.88 64.91 74.29 75.07 75.46 80.16 82.11 87.98 89.93 92.28 92.28
5200 48.88 64.91 74.29 75.07 75.46 80.16 82.11 87.98 89.93 92.28 92.28
4800 48.88 72.34 74.29 74.29 75.46 80.16 82.11 84.06 86.02 86.80 86.80
4400 48.88 72.34 74.29 74.29 79.37 84.06 86.02 87.98 89.93 89.93 89.93
4000 48.88 72.34 74.29 76.25 80.94 86.80 91.89 91.10 90.32 91.10 86.02
3600 58.65 72.34 74.29 77.03 80.94 87.58 89.93 92.28 93.84 93.84 95.80
3200 59.82 74.29 80.16 82.50 82.89 87.58 94.62 93.84 93.84 94.62 94.62
2800 58.65 80.94 82.11 83.67 84.06 87.98 91.89 92.67 93.06 93.06 91.89
2400 58.65 80.16 82.11 82.89 83.67 87.98 90.71 94.62 94.62 94.62 93.84
2000 58.65 77.81 79.76 81.33 82.11 85.24 87.58 90.71 90.71 90.71 91.89
1600 55.91 71.55 75.46 77.03 82.89 85.63 87.98 87.98 87.98 88.37 86.02
1200 47.70 59.04 68.42 73.51 74.29 77.03 80.94 80.55 82.11 82.89 83.67
800 37.15 45.36 56.30 63.73 67.64 69.21 71.55 72.73 74.29 77.03 82.11
400 31.28 41.06 46.14 50.83 52.79 62.17 62.95 65.30 67.64 70.38 78.20


15. Injector constant vs. engine vacuum (AFPR) =
kPa vac Gms/sec
(null)
0 14.30
10 14.30
20 14.30
30 14.30
40 14.30
50 14.30
60 14.30
70 14.30
80 14.30

SA (Spark Advance) Tables
yes, once you get VE close, its time to move to spark.
run no more timing than needed & watch the knock counts.
looking at a different bin for the same motor & trans as you have may give you an ideal on what you can do for spark. depending on your motor, i think you can bump 4 degrees across the board to start with, if you hear or see knock counts, back it off.
don't be surprised when your VE changes as you work on the spark table.

16. Closed Throttle SA table =

RPM kPa
20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
6000 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92
5600 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92
5200 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92
4800 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92
4400 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92
4000 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92
3600 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92
3200 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92
2800 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92
2400 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92
2000 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.57 24.57 24.57 24.57 24.57 24.57 24.57
1600 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.57 24.22 24.22 23.52 23.17 23.17 23.17
1200 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.57 23.52 22.46 21.76 21.41 21.41 21.41
1000 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.57 23.52 22.46 21.41 20.36 19.66 19.66 19.66
800 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 23.52 22.46 21.41 20.36 18.95 17.55 17.55 17.55
600 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.22 22.81 21.76 20.71 19.66 18.25 16.15 16.15 16.15
400 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.92 23.52 22.46 21.41 20.36 19.31 17.90 16.15 16.15 16.15


17. Open Throttle SA table =

RPM kPa
20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
6000 37.91 37.91 37.91 37.91 37.91 37.91 37.91 37.21 36.15 35.10 33.70 32.29 31.24 30.19 29.83 29.83 29.83
5600 37.91 37.91 37.91 37.91 37.91 37.91 37.91 37.21 36.15 35.10 33.70 32.29 31.24 30.19 29.83 29.83 29.83
5200 37.91 37.91 37.91 37.91 37.91 37.91 37.91 37.21 36.15 35.10 33.70 32.29 31.24 30.19 29.83 29.83 29.83
4800 37.91 37.91 37.91 37.91 37.91 37.91 37.91 37.21 36.15 35.10 33.70 32.29 31.24 30.19 29.83 29.83 29.83
4400 37.91 37.91 37.91 37.91 37.91 37.91 37.91 37.21 36.15 35.10 33.70 32.29 31.24 30.19 29.83 29.83 29.83
4000 37.91 37.91 37.91 37.91 37.91 37.91 37.91 37.21 36.15 35.10 33.70 32.29 31.24 30.19 29.83 29.83 29.83
3600 37.91 37.91 37.91 37.91 37.91 37.91 37.91 37.21 36.15 35.10 33.70 32.29 31.24 30.19 29.83 29.83 29.83
3200 36.85 36.85 36.85 36.85 36.85 36.85 36.85 36.50 35.45 34.40 32.99 31.59 30.54 29.83 29.48 29.48 29.48
2800 35.80 35.80 35.80 35.80 35.80 35.80 35.80 35.45 34.40 33.34 31.94 30.54 29.48 28.78 28.43 28.43 28.43
2400 34.75 34.75 34.75 34.75 34.75 34.75 34.75 34.05 33.34 32.29 30.54 29.13 28.08 27.38 26.68 26.68 26.68
2000 32.99 32.99 32.99 32.99 32.99 32.99 32.99 32.64 31.59 30.54 28.78 27.38 26.32 25.27 24.57 24.57 24.57
1600 31.24 31.24 31.24 31.24 31.24 31.24 31.24 30.54 29.48 28.08 26.68 25.27 24.22 23.17 22.46 22.46 22.46
1200 29.48 29.48 29.48 29.48 29.48 29.48 29.48 28.43 27.38 26.32 24.92 23.52 22.46 21.41 20.71 20.71 20.71
1000 27.73 27.73 27.73 27.73 27.73 27.73 27.73 26.68 25.62 24.57 23.52 22.46 21.06 20.01 18.95 18.95 18.95
800 26.32 26.32 26.32 26.32 26.32 26.32 26.32 25.62 24.57 23.52 22.46 21.41 20.01 18.25 17.20 17.20 17.20
600 25.27 25.27 25.27 25.27 25.27 25.27 25.27 24.92 23.87 22.81 21.76 20.71 18.95 17.20 15.09 15.09 15.09
400 24.92 24.92 24.92 24.92 24.92 24.92 24.92 24.57 23.52 22.46 21.41 20.36 18.95 17.55 15.09 15.09 15.09


18. Initial choke SA =

Deg C SA
(null)
152 0.00
128 0.00
104 0.00
80 0.00
56 0.35
32 1.05
8 1.05
-16 1.40
-40 1.40


19. SA correction vs. vac and cool temp =

Deg C kPa
80 70 60 50 40 30 20 10 0
128 0.00 0.00 0.00 -1.05 -2.11 -3.16 -3.16 -3.16 -3.16
116 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
103 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
92 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
80 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
68 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
56 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
44 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
32 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
20 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
8 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
-4 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
-16 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
-28 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00


20. PE AFR vs RPMs =

RPM AFR
(null)
6400 12.50
6000 12.50
5600 12.50
5200 12.50
4800 12.50
4400 12.50
4000 12.50
3600 12.50
3200 12.50
2800 12.50
2400 12.50
2000 12.50
1600 12.50
1200 12.20
800 12.00
400 12.00
0 12.00

PROPORTIONAL SA CONTROL?
Going through the spark minor loop and man, there is alot of cool stuff in this thing . They even have a proportional control routine meant for use with manual transmisisons. It uses the SA to control the rate that the rpms can change, probably to limit bucking when a manual is used. That should come in handy with the TKO.
with a th350 or a manual trans, just tick the flags that tell the pcm the engine has a manual trans bolted behind it, and it won't care about any trans/tcc issues..

21. Idle proportional SA overspeed adj. =
Proportional Spark: Causes Up + Down Surges

RPM error SA
(null)
250.0 -5.97
150.0 -4.91
50.0 -4.91
37.5 -3.86
25.0 -3.16
12.5 -1.75
0.0 0.00


22. Idle proportional SA underspeed adj. =
Proportional Spark: Causes Up + Down Surges

RPM error SA
(null)
250.0 3.16
150.0 3.16
50.0 3.86
37.5 3.16
25.0 2.11
12.5 0.70
0.0 0.00


23. SA derivative correction vs. transient RPM ratio =
Derivative Spark: Causes flaky engines.
RPM ratio SA
(null)
1.25 2.46
1.22 2.11
1.19 1.75
1.16 1.40
1.13 1.05
1.09 0.70
1.06 0.35
1.03 0.00
1.00 0.00
.97 0.00
.94 -0.35
.91 -0.70
.87 -1.05
.84 -1.40
.81 -1.75
.78 -2.11
.75 -2.46


24. Burst knock retard vs. cool temp =
- If below this temp, burst
knock can take place, if above this temp, only regular
knock retard can take place.

The burst knock qualification is as follows:

Option byte @ 0x006, bit 0 set (= 1)
Engine temp below knock retard threshold
Not in closed loop
Map value above threshold
TPS % above threshold
TPS differential above threshold
TPS differential is for more throttle opening

If all of the above qualifies, then a lookup is done
based on current engine temperature. This value is
subtracted from the total timing. It is not available
for output to the aldl link, but is reflected in the
value at location 0x0067.

Burst Knock is an all or nothing deal, no attack rate
or decay rate. Once started, it exists for the entire
duration set at 0x031. The actual retard value is
adjusted each pass through (80 times/second), relative
to the engine temperature (from the lookup table).

Once the Duration is met, the retard instantly ceases.

Deg C Deg SA
(null)
110 2.11
105 1.75
100 1.75
95 1.40
90 1.05
85 0.35
80 0.00
75 0.00

[1BadZ71Tahoe]

25. PE spark correction vs. RPM =
- 0x15E: PE Spark. This spark is added when at WOT. It is based
on engine rpm. I believe that a TPS is required for
the code to recognize a WOT condition.
RPM SA
(null)
6400 0.00
6000 0.00
5600 0.00
5200 0.00
4800 0.00
4400 0.00
4000 0.00
3600 0.00
3200 0.00
2800 0.00
2400 0.00
2000 0.00
1600 0.00
1200 0.00
800 0.00
400 0.00
0 0.00


26. Open loop AFR vs. cool temp and vac. =
- GM set the OL(Open Loop) AFR (Air/Fuel Ratio) to 16:1 which adds too much when cold, pulls too much when cool, then pulls when hot; which kills power once warmed up.

Deg C kPa
80 70 60 50 40 30 20 10 0
104 14.10 14.10 14.10 14.10 14.10 13.80 13.50 13.30 13.00
92 14.10 14.10 14.10 14.10 14.10 13.80 13.50 13.30 13.00
80 14.10 14.10 14.10 14.10 14.10 13.80 13.50 13.30 13.00
68 14.10 14.10 14.10 14.10 14.10 13.80 13.50 13.30 13.00
56 14.10 14.10 14.10 14.10 14.10 13.80 13.50 13.30 13.00
44 13.70 13.70 13.70 13.70 13.70 13.40 13.20 12.90 12.60
32 13.40 13.40 13.40 13.40 13.40 13.10 12.80 12.40 12.20
20 13.00 13.00 13.00 13.00 13.00 12.70 12.40 12.10 11.80
8 12.70 12.70 12.70 12.70 12.70 12.40 12.10 11.80 11.50
-4 12.20 12.20 12.20 12.20 12.20 12.00 11.70 11.50 11.00
-16 12.00 12.00 12.00 12.00 12.00 11.70 11.50 11.20 10.20
-28 12.00 12.00 12.00 12.00 11.80 11.50 11.20 11.00 10.00
-40 11.50 11.50 11.50 11.50 11.50 11.30 11.00 10.50 10.00


27. Lean open loop AFR limit vs. cool temp for idling =
- GM set the OL(Open Loop) AFR (Air/Fuel Ratio) to 16:1 which adds too much when cold, pulls too much when cool, then pulls when hot; which kills power once warmed up.

Deg C AFR
(null)
104 14.60
92 14.60
80 14.60
68 14.60
56 14.70
44 14.70
32 14.00
20 13.70
8 12.80
-4 12.60
-16 12.50
-28 12.30
-40 12.00


28. TPS threshold for WOT vs. RPM =

RPM
(null)
4000 84.85
3600 84.85
3200 84.85
2800 84.85
2400 84.85
2000 84.85
1600 84.85
1200 75.07
800 50.05


29. TPS threshold for PE vs. RPM =

RPM
(null)
4000 44.97
3600 44.97
3200 44.97
2800 44.97
2400 39.88
2000 35.19
1600 30.11
1200 25.02
800 25.02

START 30.
Decel enleanment is typically used for a short duration during throttle lift. It compensates for the fuel layer on the manifold walls evaporating under a falling MAP condition.

30. Decel enlean factor vs. manifold temp =

Deg C Mult.
(null)
152 0.56
128 0.63
104 0.72
80 0.91
56 1.13
32 1.50
8 2.00
-16 2.50
-40 3.00


31. Decel enlean PW reduction vs. delta MAP =
Delta kPa Mult.
(null)
50 34.85
45 32.47
40 30.49
35 28.12
30 25.34
25 23.36
20 19.80
15 17.03
10 12.67
5 6.34
0 0.00


32. Decel enlean PW reduction vs. delta TPS =

% TPS Mult.
(null)
100.0 40.39
93.8 40.39
87.5 40.39
81.3 40.39
75.0 40.39
68.8 40.39
62.5 40.39
56.3 40.39
50.0 40.39
43.8 40.39
37.5 40.39
31.3 30.49
25.0 20.20
18.8 15.05
12.5 10.30
6.3 5.15
0.0 0.00


33. Async. AE temp. correction vs.manifold temp =

Deg C % corr
(null)
152 0.47
140 0.53
128 0.59
116 0.66
104 0.72
92 0.84
80 1.03
68 1.34
56 1.69
44 2.19
32 2.72
20 3.28
8 3.88
-4 4.44
-16 4.94
-28 5.38
-40 5.88


34. Sync. AE temp. correction vs. manifold temp =

Deg C % corr
(null)
152 0.47
140 0.47
128 0.53
116 0.59
104 0.69
92 0.78
80 0.91
68 1.13
56 1.50
44 1.97
32 2.47
20 2.88
8 3.16
-4 3.31
-16 3.44
-28 3.53
-40 3.66


35 Start Here: That's one of the areas, that's as much art form as any thing else.

Grumpy@ThirdGen RIP: **Generally**, you want enough TPS AE on light to moderate brisk acclerations. Then just enough MAP to fill in the top.
Then, enough MAP AE for slight acclerations going up hill.

After doing a 1,000 chips, I still spend alot of time getting it right. And I'm serious about that chip count.

35. TPS AE temp correction vs. MAT =

Deg C % corr
(null)
80 1.22
68 1.25
56 1.27
44 1.31
32 1.34
20 1.39
8 1.46
-4 1.51
-16 1.56


36. MAP AE correction vs. RPMs =

RPM % corr
(null)
4800 1.00
4000 1.00
3200 1.00
2400 1.00
2000 1.00
1600 1.00
1200 1.05
800 1.08
400 1.10


Third, AE vs TPS only affects the first 2 tenths of a second or so of AE. AE vs MAP lasts around 2.5 seconds. I have found that AE vs TPS usually does not need that much added for a like type manifold swap, maybe 10 or 20 percent. AE vs MAP is most helpful for fixing a bog on accelleration. Doubling the AE vs MAP values and making sure there is an entry in the 0 map cell (some BCC's have 0 in the 0 MAP cell) is a good starting point. I have seen some single plane TBI setups that needed the AE vs MAP values quadroupled to get it right.

37. Delta MAP AE =

Delta MAP %DC
(null)
80 15.81
75 15.62
70 15.32
65 14.64
60 13.66
55 11.81
50 9.76
45 7.61
40 5.86
35 4.49
30 3.22
25 1.95
20 1.07
15 0.49
10 0.29
5 0.00
0 0.00


38. Delta TPS AE =
Fast 355:
I would not touch MAP AE just yet.

The TPS AE is more of the problem with the larger TBI. Calculate the area of the new TBI bores vs. the stock bore and adjust the AE using the % difference. Should get you pretty close.

Alvanwie:
I would agree, start with the TPS AE. Depending on all the details of your engine combo (intake manifold, cam, heads, tbi, etc.), don't be surprised if you need to increase TPS AE setting by as much as 200-500%. If the tbi was the only thing changed, maybe a calculation based on airflow increase of the tbi would be valid, but with the other changes you have made I would have no suggestions on how to calculate the AE requirements for your motor.

Remember the AE changes are only for helping to cure problems with acceleration lean pop. This has nothing to do with your BLM (VE table) adjustments.
Logging data for BLM adjustment, you should be trying to do this without engaging AE or PE as others have pointed out.


Delta TPS %DC
(null)
12.50 20.90
9.38 19.14
6.25 14.84
3.13 8.30
0.00 0.00


39. Delta IAC flow AE =

Delta %IAC flow usec
(null)
25.00 183.12
18.75 122.08
12.5 61.04
6.25 15.26
0.00 0.00


40. IAC flow vs. cool temp (P/N) = N/A For Manual Transmissions

Deg C % flow
(null)
116 28.93
104 29.72
92 30.89
80 32.45
68 35.19
56 39.10
44 46.14
32 55.13
20 64.91
8 73.12
-4 82.11
-16 89.93
-28 93.84


41. IAC flow vs. cool temp (drive) = N/A for Manual Transmission

Deg C % flow
(null)
116 28.93
104 29.72
92 30.89
80 32.45
68 35.19
56 38.71
44 45.75
32 55.13
20 64.91
8 73.12
-4 82.11
-16 89.93
-28 93.84


42. Desired idle speed vs. cool temp (D, A/C) = N/A for Manual Transmission

Deg C
(null)
116 675.00
110 675.00
104 675.00
98 675.00
92 675.00
80 675.00
68 675.00
56 700.00
44 775.00
32 850.00
20 850.00
8 900.00
-4 1000.00
-16 1000.00
-28 1000.00


43. Desired idle speed vs. cool temp (D, no A/C) = N/A For Manual Transmissions

Deg C
(null)
116 675.00
110 675.00
104 675.00
98 675.00
92 675.00
80 675.00
68 675.00
56 700.00
44 775.00
32 850.00
20 850.00
8 900.00
-4 1000.00
-16 1000.00
-28 1000.00


44. IAC throttle follower gain vs. cool temp =
- RBob's IAC article goes along way to explaining how to edit it.

It takes alot of dithering to get it right thou.

The T/F and AE run hand in hand as the throttle opens.

I think following the lead of the later aftermarkets in this one area, is an idea worth following.

Basically just tracks the throttle opening, and then a tuneable delay for closing TPS.

Too fast of closing throttle follower can make for stalls in the bleach box.

TBI is somewhat worse since your dealing with a wet manifold and at sudden closure the wet walls instantly evaporate, and leaves it rich, for an instant or longer.

The IAC, friend or foe? Can it be tamed? Only the Shadow knows. . .

Yes, part of the IAC function is for emissions. On a throttle lift it helps prevent a slug of rich fuel making its way out the tail pipe. The IAC does this by staying open and slowly decaying back to normal.

In stock form the throttle follower action is too much. I like to set it so it reaches max IAC with 100% TPS. Then I also get rid of the closing delays and increase the closing rate.

On the '8746 the IAC also gets a kick when the P/S switch is active.

Here are the throttle follower terms:
Code:
LD538: FCB 96 ; max TF steps

LD539: FCB 32 ; TF decay filt coef, < low mph
LD53A: FCB 16 ; TF decay filt coef, > low mph & < high mph
LD53B: FCB 25 ; TF decay filt coef, > high mph

LD53C: FCB 64 ; filt coef (L00BF, for DFCO & kickdown steps)
LD53D: FCB 15 ; filt coef (L00C1, for P/S Sw, Baro)

LD53E: FCB 5 ; TF decay low mph thres, between filt coef @ D539 & D53
LD53F: FCB 20 ; TF decay high mph thres, between filt coef @ D53A & D5

LD540: FCB 10 ; min TF steps if mph > low mph (LD53E)

LD541: FCB 6 ; 2.3%, TF tps% bias
LD542: FCB 32 ; TF factor in prk/neut
LD543: FCB 64 ; TF factor not in prk/neut
I haven't seen a delay term for when the throttle is lifted, befor ehte IAC starts to close. It may be there, don't know.

The last two (LD542 & LD543) control how much the IAC moves relative to the TPS. Smaller number makes it move less.

The three filter coef terms (LD539. . .) control how quickly the throttle follower (TF) steps decay out on a throttle lift. A larger number will cause the TF steps to decay faster.

The two MPH terms (LD53E . . .) define which of the three filter coeficients are used. Plus the low MPH term is used for the min TF steps at LD540. the minimum steps are always applied until the MPH is less then the lowest MPH threshold.

The bias term (LD541) is the TPS threshold that the TPS must be greater then to get TF action.

I like to set the max TF steps (LD538) to a high value as to get as much airflow as possible.

Can check the data logs comparing the IAC steps to TPS% for an idea of how the TF steps operate. Also check when DFCO becomes active as this will add IAC steps.

RBob.

Deg C gain
(null)
116 2.39
104 2.39
92 2.39
80 2.39
68 2.39
56 2.39
44 2.39
32 2.39
20 2.39
8 2.53
-4 2.73
-16 3.14
-28 3.28


45. Min closed throttle IAC T/F TPS reduction vs. MPH =

MPH % reduction
(null)
36 0.00
32 0.00
28 0.00
24 0.00
20 0.00
16 49.61
12 87.89
8 99.61
4 99.61
0 99.61


46. Lower limit for T/F TPS when closed throttle present vs. cool temp =

Deg C % T/F TPS
(null)
116 3.03
104 3.03
92 3.03
80 3.03
68 3.03
56 3.03
44 3.03
32 3.03
20 3.03
8 3.03
-4 3.03
-16 3.03
-28 3.03


47. IAC T/F TPS filtering period vs. MPH =

MPH secs
(null)
80 1.50
72 1.50
64 1.50
56 1.50
48 1.50
40 1.50
32 1.50
24 1.50
16 0.75
8 0.50
0 0.20


48. IAC T/F TPS filtering coeff. vs. MPH =

MPH Coeff.
(null)
80 5.00
72 5.00
64 5.00
56 5.00
48 5.00
40 5.00
32 5.00
24 5.00
16 10.00
8 15.00
0 25.00

Am I giving too much away?

[Red94Chev]

This is useful I'm sure, but I think it would be more helpful to have a "how to" guide with a set of instructions using datalogging (sensor feedback) to make changes to the appropriate tables to properly tune any engine combination. This would include camshaft or cylinder head changes, engine displacement, installing larger fuel injectors, installing a higher stall torque converter, etc. Also, explaining the reasoning behind the changes will be important for anyone who chooses to write the tuning guide. Liberal use of figures and sheetshots with the key features explained would also be helpful. To generate a tuning guide would take a considerable amount of time to do the subject matter the justice it deserves, so I understand when Fast305 says he doesn't have the time. Right now, there is no reference point to understand the data presented.

As a side note, this area of performance modifications is the least understood area for the average performance enthusiast, but it perhaps the most important mod to perform when it comes to making your fuel-injected engine combination work as expected. Take the performance magazines as an example. The focus is on testing the particular parts combination on a fuel-injected engine and then the author will write a line like, " ...and then we took our car to X Tuning Co where they dialed in our combination." Usually an oversight. Since a significant and popular portion of this forum is dedicated to sharing and asking questions about performance-enhancing techniques about fullsize GM trucks, it is surprising that there has not been a tuning guide sticky written given the depth of experience of the FSC members that frequent here. Yes, of course there are a number of options available like mail-order tuning or having an experienced professional perform the tune, but wouldn't it be great to have an easy-to-read guide for the average DIY enthusiast? I'm attempting to learn it myself, but the learning curve is fairly steep. I'm sure I'll get there eventually, but a handy tuning guide to refer to would be fantastic IMO.

[1BadZ71Tahoe]

This is useful I'm sure, but I think it would be more helpful to have a "how to" guide with a set of instructions using datalogging (sensor feedback) to make changes to the appropriate tables to properly tune any engine combination. This would include camshaft or cylinder head changes, engine displacement, installing larger fuel injectors, installing a higher stall torque converter, etc. Also, explaining the reasoning behind the changes will be important for anyone who chooses to write the tuning guide. Liberal use of figures and sheetshots with the key features explained would also be helpful. To generate a tuning guide would take a considerable amount of time to do the subject matter the justice it deserves, so I understand when Fast305 says he doesn't have the time. Right now, there is no reference point to understand the data presented.

As a side note, this area of performance modifications is perhaps the least understood area for the average performance enthusiast, but it perhaps the most important mod to perform when it comes to making your fuel-injected engine combination work as expected. Take the performance magazines as an example. The focus is on testing the particular parts combination on a fuel-injected engine and then the author will write a line like, " ...and then we took our car to X Tuning Co where they dialed in our combination." Usually an oversight. Since a significant and popular portion of this forum is dedicated to sharing and asking questions about performance-enhancing techniques about fullsize GM trucks, it is surprising that there has not been a tuning guide sticky written given the depth of experience of the FSC members that frequent here. Yes, of course there are a number of options available like mail-order tuning or having an experience professional perform the tune, but wouldn't it be great to have an easy-to-read guide for the average DIY enthusiast? I'm attempting to learn it myself, but the learning curve is fairly steep. I'm sure I'll get there eventually, but a handy tuning guide to refer to would be fantastic IMO.

Now don't get me wrong, but i think you'll find later on with the numerous quantity of ECU/PCM's and all of their different characteristics, it's going to be really really hard to even design a "general" tuning how-to. There are tons of different functions between ECU's; SD (7747 for example) VS MAF (7427) just to name one difference. With speed density, you have to continuously limbo between fuel and spark tables, whereas with MAF all you do is change your airflow tables.

My caprice on the other hand is a 6395 ECU, which has very limited information on it, only TunerCat currently supports it, but you can datalog with WinALDL under another ECU #.

IMHO, there's no easy way because it's going to take all sorts of different fooling around with each ECU, to get it to run properly. I believe it's best sorted out by ECU (There are Masks for each ECU, which I can't even get into in this post), which complicate the process even further.

JMO

I'll wait for the real "experts" to chime in, before I keep blabbing. :whatever:

- B

EDIT: To generate a tuning guide would take a considerable amount of time to do the subject matter the justice it deserves, so I understand when Fast305 says he doesn't have the time. Right now, there is no reference point to understand the data presented.

I have taken 0 offense, but if this was directed towards me, I have written tons upon tons of information about how to do this swap on other posts in this message board. Perhaps you need to continue to read, read, and when you just begin to understand it, read is 10 more times. My post with all this data I just copied and pasted can be fully explained in my 7427 w/ MAF How To Guide which I put everything in lamens terms for everyone which is one of the top 5 posts at the moment. Why it hasn't been considered a sticky, I don't know, but it doesn't matter, i'm just trying to help you guys out.

- B

[Zero260]

1Bad,

First I have to say, it is VERY cool of you to volunteer and put the time in to post this information. The info on this thread, and on your "How-to.." thread is definately worth some money. If I had put the time into getting that thread and the posts on this thread together, and it didnt get sticked, I'd get more than a little offended.

Maybe an easier way for the author(s), would be to put together a powerful/dependable engine combo, ran by the MAF/7427 setup, and give instructions on how to tune it. The budget 350/lt4 cam engine Fast305 wrote up would be a great example. Or maybe a 383
stroker verison.

And also show comparisons between the "new" tune and the "stock" tune. That way, it would be easier for someone who mastered the "write-up" tune to branch out and move on to a more complicated setup. That would help a person like me out. I tend to learn by example and use reading material as a fall back when I get to a roadblock.

I don't know how it would be setup. But I do know that time = money. If somehow an organized donation/compensation deal could be setup, I know I'd contribute.

[Red94Chev]

I have taken 0 offense, but if this was directed towards me, I have written tons upon tons of information about how to do this swap on other posts in this message board. Perhaps you need to continue to read, read, and when you just begin to understand it, read is 10 more times. My post with all this data I just copied and pasted can be fully explained in my 7427 w/ MAF How To Guide which I put everything in lamens terms for everyone which is one of the top 5 posts at the moment. Why it hasn't been considered a sticky, I don't know, but it doesn't matter, i'm just trying to help you guys out.

- B

No part of my post was directed at anyone. Just speaking generally...and more of a statement of my lack of knowledge in the subject area. So many tables and not really sure what each of them do yet. Believe me, I'm reading as much as I can.

In terms of who decides what is sticky material, I don't think a moderator can go through the large number of posts here to determine which posts to sticky. Send an private message to one of the moderators highlighting your contribution. For anyone reading this thread, 1BadZ71Tahoe's excellent contribution can be found here: http://www.fullsizechevy.com/forums/general-discussion/performance/tbi-tuning-87-95-obd-i-ecm-pcm/299728-0d-7427-w-maf-how-compilation.html

I've also read Fast305's excellent thread at TGO (aka Fast355) about his budget tbi build-up: http://www.thirdgen.org/techboard/tbi/391406-budget-tbi-buildup.html

There is also an attempt to piece together threads about TBI tuning techniques via one thread. Lots of reading though: http://www.thirdgen.org/techboard/tbi/257455-advanced-topics-tbi-theory.html

I guess when I say a tuning guide, I really mean a step-by-step methological approach to tuning using TunerRT PRO. The closest example I have seen is the Holley's Manual for the Commander 950. A very, VERY good read: http://www.holley.com/data/Products/Technical/199R10149-7.pdf