L31 to LT1 swap?

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McBroom

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Depending on the year it should still be the p01 or p59. The 0411 that I used to convert my 98 suburban with a 5.7 was originally out of a v6 blazer, 2002 if I remember correctly. It can run both. It's just a different OS.
It's a '91 Cheyenne.
My apologies for high jacking the thread.

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McBroom

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Depending on the year it should still be the p01 or p59. The 0411 that I used to convert my 98 suburban with a 5.7 was originally out of a v6 blazer, 2002 if I remember correctly. It can run both. It's just a different OS.
Here's a pic of it. Its been sitting since 2016.
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Hobie

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It's a '91 Cheyenne.
My apologies for high jacking the thread.

The Blue Mule
A 91 doesnt have a PCM, it will have a TBI chip (I'm not sure what they are actually called) the 96-98 had black box computers, and the 99+had a PCM IIRC
 

Supercharged111

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A 91 doesnt have a PCM, it will have a TBI chip (I'm not sure what they are actually called) the 96-98 had black box computers, and the 99+had a PCM IIRC

It'd be an ECM if it's pre-4L60. Once the 4L60 came out they were called PCMs.
 

Mark Gilbert

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But the black box is considered an ECM, not a PCM. Or was the information that I was given wrong?

The black box is a PCM

PCM - Powertrain control module
ECM - Engine control module

The blackbox wasn't used until 96. with the vortec motors. They stopped using it in 1999 or 2000 depending on the model I think. Before the blackbox the motors were all TBI instead of Multiport injection.

Depending on the tranny you had you would have one or the other,and considering yours is a V6 it would be an ECM, so you probably don't have the 4l80. (just noticed the post that said you had a 5 speed, so obviously don't have a 4l80) The reality is that it doesn't really matter unless you are changing one out. If you have a computer controlled tranny then it would be a PCM. In 1991 the 4l80 was used and it required a PCM, but I believe 94 half ton would only have an ECM.

You probably have the 1227747 ECM. Here are some details about your ECM

http://www.gearhead-efi.com/Fuel-Injection/showthread.php?304-1227747-ECM-Information-42
 

Hobie

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The black box is a PCM

PCM - Powertrain control module
ECM - Engine control module

The blackbox wasn't used until 96. with the vortec motors. They stopped using it in 1999 or 2000 depending on the model I think. Before the blackbox the motors were all TBI instead of Multiport injection.

Depending on the tranny you had you would have one or the other,and considering yours is a V6 it would be an ECM, so you probably don't have the 4l80. (just noticed the post that said you had a 5 speed, so obviously don't have a 4l80) The reality is that it doesn't really matter unless you are changing one out. If you have a computer controlled tranny then it would be a PCM. In 1991 the 4l80 was used and it required a PCM, but I believe 94 half ton would only have an ECM.

You probably have the 1227747 ECM. Here are some details about your ECM

http://www.gearhead-efi.com/Fuel-Injection/showthread.php?304-1227747-ECM-Information-42
The truck posted isnt mine, I have a 96 with a vortec 350, the one I am planning on swapping to an LT1. I knew the TBI chips were considered ECMs, but I was also given information that the black box was an ECM as well. I figured that if the transmission was controlled by the same computer as the engine it would be a PCM, but in that same case a 95/94 TBI would have a PCM, yet are still considered an ECM
 

McBroom

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The truck posted isnt mine, I have a 96 with a vortec 350, the one I am planning on swapping to an LT1. I knew the TBI chips were considered ECMs, but I was also given information that the black box was an ECM as well. I figured that if the transmission was controlled by the same computer as the engine it would be a PCM, but in that same case a 95/94 TBI would have a PCM, yet are still considered an ECM
The posts about the V6/5 spd man. Are mine. I apologize for the short hijack on your thread. Back to our regularly scheduled program

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Hobie

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The posts about the V6/5 spd man. Are mine. I apologize for the short hijack on your thread. Back to our regularly scheduled program

The Blue Mule
No worries man! I'm all for the spreading of knowledge! My part of the thread will be on hold, LT1 will be pulled mid spring, so not too much I can do until then
 
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