Author Topic: 87 4x4 6.0/6l90 swap  (Read 20021 times)

Offline jobobcat18

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87 4x4 6.0/6l90 swap
« on: April 29, 2018, 02:30:28 AM »
This is my first post and I'm new forums in general. I also tried to post 4 times in tapatalk and just kept getting errors. So if there are numerous posts by my I apologize. I just bought a 2016 van l96 6.0 and 6l90 with the e78 ecm and harness and everything I need running gear wise (I'm not 100% sure what all I need) for 3600 with 3600 miles. To bolt the transmission up to my np208, I'm going to cut the output shaft down and send it off to be cut down and resplined to a 32 spline input for the 208 (I've read how 4 low may not work but I dont use it). Also I have to get the adapter for it. I also plan on keeping my dual tank setup. This is the first ls swap that any of us swapping it have ever done. Any tips would sure be appreciated. And does anyone know how to make the oil pan fit above the front crossmember on a 4x4? Or what oil pan to get? Thanks!

Offline jobobcat18

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Re: 87 4x4 6.0/6l90 swap
« Reply #1 on: April 29, 2018, 02:35:27 AM »
I will also be updating this post and once finished I will post a full part list for everything I used and done to make everything work.

Offline Rapid Roy

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Re: 87 4x4 6.0/6l90 swap
« Reply #2 on: April 29, 2018, 07:59:47 AM »
Welcome.
1974 Cheyenne 10 LWB STOCK 350 W HEI /TH350/AC/4 BBL Quadrajet
Mopar by Birth
Chevy by Choice

Offline jobobcat18

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Re: 87 4x4 6.0/6l90 swap
« Reply #3 on: April 29, 2018, 11:55:35 AM »
Welcome.
Thanks rapid!

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Offline Oldblue

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Re: 87 4x4 6.0/6l90 swap
« Reply #4 on: April 29, 2018, 09:11:10 PM »
Yea man welcome!
Old Blue,

One day it'll be restored
1984 C10 SWB
Currently Project: patch panel for bed and body work

Offline jobobcat18

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Re: 87 4x4 6.0/6l90 swap
« Reply #5 on: April 30, 2018, 10:17:14 AM »
Yea man welcome!
Thanks buddy!

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Offline Jason S

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Re: 87 4x4 6.0/6l90 swap
« Reply #6 on: April 30, 2018, 02:09:18 PM »
You might check out this thread with a 6.0 LS swap:
http://forum.73-87chevytrucks.com/smforum/index.php?topic=34079.0
1973 GMC K2500, Super Custom, Camper Special, 350, TH350, NP203, 4.10's
1974 Chevrolet K10, Custom Deluxe, 350, SM465, NP203, 3.73's

"1) Peace through strength; 2) Trust but verify; 3) Beware of evil in the modern world"

Offline jobobcat18

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Re: 87 4x4 6.0/6l90 swap
« Reply #7 on: April 30, 2018, 08:26:04 PM »
You might check out this thread with a 6.0 LS swap:
http://forum.73-87chevytrucks.com/smforum/index.php?topic=34079.0
Will do. Thanks!

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Offline jobobcat18

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Re: 87 4x4 6.0/6l90 swap
« Reply #8 on: May 01, 2018, 11:54:10 AM »
Does anyone know anything about creating a standalone harness for an e78 ecm?

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Offline roundhouse

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Re: 87 4x4 6.0/6l90 swap
« Reply #9 on: May 11, 2018, 09:04:08 PM »
I did harness  work for mine but it was a 2002 model
And if i had it to do over again I would have some one else do the harness work
You’re going to have to have someone redo the software on the computer anyway
Have them do the harness too

There are cheaper places but I used “Team208motorsports “

Offline jobobcat18

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Re: 87 4x4 6.0/6l90 swap
« Reply #10 on: May 11, 2018, 09:21:56 PM »
I did harness  work for mine but it was a 2002 model
And if i had it to do over again I would have some one else do the harness work
You’re going to have to have someone redo the software on the computer anyway
Have them do the harness too

There are cheaper places but I used “Team208motorsports “
I gotcha. I would do that but the budget doesnt allow for it. Do you know how to run the ac? Mine is already r134 converted. But the wiring that needs to be done in order for the computer to increase the idle.

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Offline roundhouse

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Re: 87 4x4 6.0/6l90 swap
« Reply #11 on: May 14, 2018, 09:39:55 PM »
I did harness  work for mine but it was a 2002 model
And if i had it to do over again I would have some one else do the harness work
You’re going to have to have someone redo the software on the computer anyway
Have them do the harness too

There are cheaper places but I used “Team208motorsports “
I gotcha. I would do that but the budget doesnt allow for it. Do you know how to run the ac? Mine is already r134 converted. But the wiring that needs to be done in order for the computer to increase the idle.

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Not sure about the ac idle up

But there is a wire that signals the computer that the ac is on

Not a big deal without it

We don’t have it hooked up and haven’t noticed
It’s a V8 , if it was a four banger you’d need the idle up

Offline jobobcat18

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Re: 87 4x4 6.0/6l90 swap
« Reply #12 on: May 15, 2018, 11:15:08 AM »
I did harness  work for mine but it was a 2002 model
And if i had it to do over again I would have some one else do the harness work
You’re going to have to have someone redo the software on the computer anyway
Have them do the harness too

There are cheaper places but I used “Team208motorsports “
I gotcha. I would do that but the budget doesnt allow for it. Do you know how to run the ac? Mine is already r134 converted. But the wiring that needs to be done in order for the computer to increase the idle.

Sent from my SM-G955U using Tapatalk

Not sure about the ac idle up

But there is a wire that signals the computer that the ac is on

Not a big deal without it

We don’t have it hooked up and haven’t noticed
It’s a V8 , if it was a four banger you’d need the idle up
That is a good point. I appreciate it.

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Offline jobobcat18

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Re: 87 4x4 6.0/6l90 swap
« Reply #13 on: May 15, 2018, 11:22:37 AM »
I understand the pollak high psi selector valve (65 psi) can be used to run the dual tank setup. However, can this valve handle a 340 lph pump?

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Offline ehjorten

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Re: 87 4x4 6.0/6l90 swap
« Reply #14 on: May 15, 2018, 12:16:28 PM »
What size is the pump outlet?  Probably -6 AN, which is 3/8".  The Pollack valve has 3/8" Feed.  Most sites will tell you that -6 AN is capable of supporting up to 500 hp.

Your 340 lph pump only flows 340 lph at freeflow (0 psi).  It doesn't flow that at 60 psi.  Plus your injectors will only flow so much.
-Erik-
1991 V3500 - Gen V TBI 454, 4L80E, NP205, 14 bolt FF, D60, 8" Lift on 35s
1977 K20 Silverado - 350, THM350, NP203, 14 bolt FF, D44, Stock Lift on 31s
1969 Chevelle Malibu Sport Coupe - EFI350, THM350
1968 Chevrolet Step-side Pickup - 300HP L6