Author Topic: 87 4x4 6.0/6l90 swap  (Read 1259 times)

Offline jobobcat18

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Re: 87 4x4 6.0/6l90 swap
« Reply #30 on: July 11, 2018, 09:58:30 AM »
I did look at that website. Only problem. I have is that my e78 ecm and the e38 ecm have quite a few differences. But I think I got it, had to use gmupfitter.com to get my harness pinout diagram and just kinda winged it from there

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Offline ehjorten

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Re: 87 4x4 6.0/6l90 swap
« Reply #31 on: July 11, 2018, 01:31:32 PM »
Usually the psi rating is a safe working pressure...at 65 psi it isn't going to burst!  I will let you know how mine works as that is how I plumbed mine.
-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

Offline jobobcat18

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Re: 87 4x4 6.0/6l90 swap
« Reply #32 on: July 22, 2018, 08:42:04 PM »
Usually the psi rating is a safe working pressure...at 65 psi it isn't going to burst!  I will let you know how mine works as that is how I plumbed mine.
Sounds good

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Offline frotosride

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Re: 87 4x4 6.0/6l90 swap
« Reply #33 on: August 09, 2018, 06:21:01 PM »
It has been a while since I have been on here but I like the swP idea and progress so far. I noticed you plan on keeping the VVT and I really intrested in seeing how it works out! Do your engine have Displacement On Demand?  When. You get to the point of flashing the ECM/PCM I highly recommend Brendan at lt1swap.com he is diligent and will work with you if there are any problems. You may try asking him about the wiring differences with your computer. If you are still working on the harness I highly recommend writing down the numbers for each color connection the pull each pin and work them out after all are unplugged. Have you found an adapter for the np208?
"Beat it like a red-headed ford"
1987 v10 Silverado 4" RC, 35's, 700R-4, 3.73
2006 Boulevard M109R 109 cid, straight pipes, PCMlll,k&n
2009 Jeep XK, 2" lift springs in mail (future LS Swap)
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Offline jobobcat18

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Re: 87 4x4 6.0/6l90 swap
« Reply #34 on: August 11, 2018, 04:34:16 PM »
I've talked to Brendan, he is still working on understanding my ecm as it's different than the e38. Also I did find an adapter, 15724745, I'll take some pictures when I go back home and upload them. I bought a 32 spline input to go into my np208, then I'll send off my output shaft in the transmission and get them to match it to my 32 spline input. The downfall is I'm not going to have 4 low working. However with 4.10 gears and the monster first in the 6l90, I dont care nor do I ever use it now. I also dont have to worry about redoing my speedometer as the transmission communicates with the ecm with an output shaft speed sensor. So the mechanical speed signal it is! In addition, the ly6 and l96 have vvt but no displacement on demand. I've just seen alot of benefits from the vvt and feel like that's the best way to go to keep it a friendly daily driver and have some nice power.

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Offline jobobcat18

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Re: 87 4x4 6.0/6l90 swap
« Reply #35 on: August 11, 2018, 04:35:35 PM »
I have also finished my harness. I'm reusing the fuse box from the van (which took a hot minute to figure out). There are a few extra relays I'll have to add to make it work but it shouldn't be an issue.

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