Ls swap into a 96-98 obs

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5.3_silverado

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I am making this thread for my truck and other people that are doing ls swaps in their 96-98 obs. I am doing the swap in my 98 ext cab and wanted to resuse as much of the harness as possible. So I can have the factory looking swap and still keep everything clean. There are some sensors and and components that will require cutting and soldering the wires together. I want to route the harness behind the intake and heads and keep it tucked by the firewall. So bare with me on this and as i start doing the wiring on it Ill keep everyone posted and post pics up as the project goes along.
This is for lm7 vin T or Z. I am doing the e85 conversion on mine so both will be up here. This is drive by wire.
 
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5.3_silverado

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Numbers 1-80 are the ECM Connector pins. Connector 1, Blue 0411 ECM
1. C3-18
2. Splice in 12 Volt wire from the crank shaft sensor.
3. C2-32
4. C2-11
5. Not Used
6. Not Used
7. Not Used
8. Not Used
9. Not Used
10. Not Used
11. Splice in for the Knock Senor #2
12. C1-31
13. Not Used
14. Splice in for Drive By Wire
15. Splice in for Drive By Wire
16. Not Used
17. Not Used
18. C3-11
19. C4-18
20. C3-21
21. C1-28
22. Not Used
23. Not used
24. C3-18
25. Not Used
26. C1-7
27. C3-18
28. Not Used
29. C1-25
30. Not Used
31. Not Used
32. C3-23
33. C4-10
34. Splice in from the Park/Neutral Switch
35. Not Used for Auto Trans. Is used for the Clutch Pedal Switch
36. C2-8
37. C2-16
38. Not Used
39. Not Used
40. C3-17
41. Not Used
42. Splice in from Relay for Fan
43. C2-12
44. C2-31
45. Splice in if using the A/C
46. Not Used
47. Not Used
48. C3-27
49. Not Used
50. Not Used
51. C2-19
52. Not Used
53. C3-16
54. C3-19
55. Not Used
56. For the e85 Conversion
57. C3-21
58. C4-11
59. Not Used
60. Not Used For Cable Throttle
61. C1-8
62. Not Used
63. Not Used
64. C3-18
65. Not Used
66. C1-21
67. C3-17
68. Not Used
69. C1-19
70. Not Used
71. Not Used
72. C3-22
73. C1-3
74. C2-23
75. C4-18
76. C2-15
77. C2-9
78. Not Used
79. C1-13
80. C3-4

Connector 2, Green 0411 ECM
1. C3-18
2. C2-7
3. Not Used
4. Not Used
5. Not Used
6. C3-6
7. Not Used
8. C3-16
9. C4-1
10. C3-9
11. Not Used
12. Not Used
13. Not Used
14. Splice in if using A/C
15. Not Used
16. Not Used
17. Not Used
18. Not Used
19. Not Used
20. C1-29
21. C1-30
22. Not Used
23. Not Used
24. Not Used
25. C2-22
26. Splice in for Bank 2 Sensor 1 H02S
27. Splice in for Ground
28. Not Used
29. Splice in for Bank 1 Sensor 1 H02S
30. Not Used
31. C2-28
32. C2-21
33. Splice in for the Brake Switch
34. Not Used
35. Not Used
36. Not Used
37. Not Used
38. Not Used
39. Not Used
40. C3-18
41. Not Used
42. C1-10
43. Splice in for A/C
44. Not Used
45. Not Used
46. C4-5
47. C2-4
48. C2-6
49. Not Used
50. C4-4
51. C2-27
52. Not Used
53. Not Used
54. Splice in for e85 Conversion
55. Not Used
56. Not Used
57. C2-22
58. Not Used
59. Not Used
60. Not Used
61. Splice in for Low Reference Cam Sensor
62. C3-11
63. C3-23
64. Not Used
65. Not Used
66. Splice in for Bank 2 Sensor 1 H02S
67. Splice in for Ground
68. Not Used
69. Splice in for Bank 1 Sensor 1 H02S
70. Not Used
71. Not Used
72. Splice in for Bank 1 Sensor 1 H02S
73. Not Used
74. Splice in from Bank 2 Sensor 1 H02S
75. Splice in from Ignition Switch
76. Not Used
77. Not Used
78. Not Used
79. Not Used
80. Splice in from A/C
 
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5.3_silverado

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Hope this helps someone. Ill be doing my swap here in the next couple days.
 

GMRedline

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Very nice. I hope this isn't a dumb question but...

Are you doing this swap for your 350 or for a LS?
 

DRAGGIN95

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Sounds like every vortec 305 or 350 I have owned, every one of them has gone to crap in short order, I will not own another one, been burned too many times.
 

5.3_silverado

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Sounds like every vortec 305 or 350 I have owned, every one of them has gone to crap in short order, I will not own another one, been burned too many times.
That is the second one in under 60,000. Those motors don't like me. My Tahoe has a 5.3. 200,000 still strong.
 

5.3_silverado

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Resealing the oil pan and rear main seal before dropping it in.
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