LS4 to LS2/3/7 throttle body thread
#1
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For those who still google- Read this
Ls3 and ls7 (gold blade) throttle bodies are one in the same they are compatible for years 05,06,08,09 LS4s
If you have a 07 at this time ls2 (silver blade) is the only one compatible.
the harness for TB swap is only needed for 05 to 07 ls4s with 8 pin connectors which need to have 6 pin for the tb upgrade. All 08 and up ls4s are a direct plug in since they are 6 pin.
EDITED: first off thanks to fieroguru, DavidGXP, and GXP25 for their research in this area the FSM GXP25 provided was the last unknown for this swap turns out my alldata Ls4 wiring diagram was wrong, so i deleted it out of the original post please disregard quotes of the orginal in posts mentioned below..
**This is a general guide ALWAYS verify your year TB pinouts first**
PINOUTS ARE AS FOLLOWS
LS2 GTO TB . LS4 TB
PIN A ---- PIN F
PIN B ---- PIN E
PIN C ---- PIN H
PIN D ---- PIN A
PIN E ---- PIN B
PIN F ---- PIN D
NOT USED PIN G&C ON THE LS4 HARNESS
**If you have idle surge or hanging idle see post#10
![Name: 300qtj6_zps564f0652.png
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PARTS LIST:
TB adapter here 55 USD http://www.alpermotorsports.com/inde..._detail&p=1688
Pigtail: LS2 Throttle Body Pigtail Brand New LS2 TB Pigtail | eBay
Throttle body: Ebay got mine for 140 shipped
all bolts are m6 x 1.0 you will need 4 for the TB and 3 are included with the TB adapter to the intake manifold
Thickness of LS2 TB for bolt length
![Name: IMG_20130411_093311_zpsbf3e06ab.jpg
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Size: 158.0 KB](https://ls1tech.com/forums/attachments/ls4-performance/678542d1501791986-ls4-ls2-3-7-throttle-body-thread-img_20130411_093311_zpsbf3e06ab.jpg)
Adapter
Ls3 and ls7 (gold blade) throttle bodies are one in the same they are compatible for years 05,06,08,09 LS4s
If you have a 07 at this time ls2 (silver blade) is the only one compatible.
the harness for TB swap is only needed for 05 to 07 ls4s with 8 pin connectors which need to have 6 pin for the tb upgrade. All 08 and up ls4s are a direct plug in since they are 6 pin.
EDITED: first off thanks to fieroguru, DavidGXP, and GXP25 for their research in this area the FSM GXP25 provided was the last unknown for this swap turns out my alldata Ls4 wiring diagram was wrong, so i deleted it out of the original post please disregard quotes of the orginal in posts mentioned below..
**This is a general guide ALWAYS verify your year TB pinouts first**
PINOUTS ARE AS FOLLOWS
LS2 GTO TB . LS4 TB
PIN A ---- PIN F
PIN B ---- PIN E
PIN C ---- PIN H
PIN D ---- PIN A
PIN E ---- PIN B
PIN F ---- PIN D
NOT USED PIN G&C ON THE LS4 HARNESS
**If you have idle surge or hanging idle see post#10
![Name: 300qtj6_zps564f0652.png
Views: 14666
Size: 100.9 KB](https://ls1tech.com/forums/attachments/ls4-performance/678541d1501791986-ls4-ls2-3-7-throttle-body-thread-300qtj6_zps564f0652.png)
PARTS LIST:
TB adapter here 55 USD http://www.alpermotorsports.com/inde..._detail&p=1688
Pigtail: LS2 Throttle Body Pigtail Brand New LS2 TB Pigtail | eBay
Throttle body: Ebay got mine for 140 shipped
all bolts are m6 x 1.0 you will need 4 for the TB and 3 are included with the TB adapter to the intake manifold
Thickness of LS2 TB for bolt length
![Name: IMG_20130411_093311_zpsbf3e06ab.jpg
Views: 9616
Size: 158.0 KB](https://ls1tech.com/forums/attachments/ls4-performance/678542d1501791986-ls4-ls2-3-7-throttle-body-thread-img_20130411_093311_zpsbf3e06ab.jpg)
Adapter
![Name: IMG_20130411_092939_zps0ce4141e.jpg
Views: 9799
Size: 116.4 KB](https://ls1tech.com/forums/attachments/ls4-performance/678543d1501791986-ls4-ls2-3-7-throttle-body-thread-img_20130411_092939_zps0ce4141e.jpg)
Last edited by 91parkave; 07-23-2018 at 06:30 AM. Reason: Corrected info and diagram
#4
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Looks good. It should work. However, I read in a thread on here somewhere about output voltage issues.
At any rate, what I've leaned from GM pinouts is that it's actually the circuit number that matters more than the "function" and definitely the wire colors. The usefulness of the circuit numbers really shines in the schematics.
At any rate, what I've leaned from GM pinouts is that it's actually the circuit number that matters more than the "function" and definitely the wire colors. The usefulness of the circuit numbers really shines in the schematics.
#8
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For issues with idle like i eventually had you will need to adjust 2 tables in the pcm
etc area scaler
for LS2 silver blades 4725.00
for ls3/7 use 5350.00
ETC scaler and Base idle airflow need to be adjusted to get you idling right.
here are the values i used with good sucess results may vary.
etc area scaler
for LS2 silver blades 4725.00
for ls3/7 use 5350.00
ETC scaler and Base idle airflow need to be adjusted to get you idling right.
here are the values i used with good sucess results may vary.
![Name: IDLE_zps469e7819.jpg
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Last edited by 91parkave; 07-23-2018 at 06:54 AM.
#19
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If I got an ls1 or ls6 intake will they bolt on without any modifications. Also do you know which one would be better than the other. Would I need to get the whole fuel rails, injectors, and and throttle body. Sorry if I have a lot of questions. I'm used to the 3800 platform. This is my first LS engine.
#20
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
If I got an ls1 or ls6 intake will they bolt on without any modifications. Also do you know which one would be better than the other. Would I need to get the whole fuel rails, injectors, and and throttle body. Sorry if I have a lot of questions. I'm used to the 3800 platform. This is my first LS engine.