Wiring 5.3 swap into square body

Donated a door to the cause and looked at my buddies wiring job. 5.3 out of 02 suburban swapped into a square body short bed 4x4. Th350 and 205 case.

Looks stupid simple. He took the under hood electrical box, computer, harness and motor. He fed that big box with a hot, ground and the wire that went to the hei. He used the square harness to run dash Guages. Pretty clean and simple. I'm going to use the same method when I swap the 8.1 out of my 02 suburban into my 86 cab and chassis except I'm using the 4l80 against the 205 case so I have an overdrive. I'm going to use a pair of tbi saddle tanks and a suburban rear tank with ep381 pumps and 2 selector switches. Fuel ups should give me a heart attach

Moofus02 said:

Donated a door to the cause and looked at my buddies wiring job. 5.3 out of 02 suburban swapped into a square body short bed 4x4. Th350 and 205 case.

Looks stupid simple. He took the under hood electrical box, computer, harness and motor. He fed that big box with a hot, ground and the wire that went to the hei. He used the square harness to run dash Guages. Pretty clean and simple. I'm going to use the same method when I swap the 8.1 out of my 02 suburban into my 86 cab and chassis except I'm using the 4l80 against the 205 case so I have an overdrive. I'm going to use a pair of tbi saddle tanks and a suburban rear tank with ep381 pumps and 2 selector switches. Fuel ups should give me a heart attach

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That's similar to what I'm doing. Factory L29/4L80 from a 97 suburban into my 1980 K25 pickup. I have already fit a 91 Blazer tank into the rear and removed the saddle tanks. Converted the L29 to CNP using an EFI connection 24x reluctor and using the factory 97 wiring harness and fuse box converted to an 0411. I'm using an 02 8.1L operating system as the baseline and going from there.

I put in a long 2wd output shaft when I rebuilt the 4L80 and will cut it down to match the old TH400 shaft length plus the 3/4" I gained from the adapter plate to convert the TH400 index ring size on the figure 8 NP205 adapter to the 4L80 size. I also have a 90 Suburban gauge cluster that will be going in at the same time with a tach, so that I can have the trip meter and an electric speedometer. The biggest thing with the wiring is that the old wiring going through the two fusible links off the starter goes away. You basically can just cut them off right after the firewall connector and run them off the fuse block. Alternator wire then gets a big 8 gauge fusible link wire straight to the battery and then the circuit breaker protected 8 gauge across the radiator to the fuse block on the drivers side. There's also some changes to the AC wiring and also fuel sending unit wiring changes to get everything plugged into the PCM and functioning right.

I have this harness in my que to purchase. Easier and cleaner than spending hours adapting a stock harness over. They claim USA built as well.

L31MaxExpress said:

I have this harness in my que to purchase. Easier and cleaner than spending hours adapting a stock harness over. They claim USA built as well.

DRIVE BY CABLE DBC 1997-2006 STANDALONE WIRING HARNESS W/ 4L80E 4.8 5.

This harness is a 5 wire MAF and a 1 wire alternator. FREE ADAPTER Connectors TO CONVERT Harness TO DELPHI MULTI 4.8 5.3 or 6.0) Injectors. All other sellers will give you 3 wire that you have to convert to 5 wire and ev1 injector connectors that u have to convert to delphi. Lots of extra costs...

highperformanceinjectors.com

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Nice, I've never heard of them but those look pretty good. If I ever have issues with my harness I might have to look into this one. I'd probably go with these guys if I ever end up putting my Gen IV 5.3 into something stupid.

Looks like they have a perfect one for his application too. https://highperformanceinjectors.co...lone-wiring-harness-t56-or-non-electric-trans

BeXtreme said:

Nice, I've never heard of them but those look pretty good. If I ever have issues with my harness I might have to look into this one. I'd probably go with these guys if I ever end up putting my Gen IV 5.3 into something stupid.

Looks like they have a perfect one for his application too. https://highperformanceinjectors.co...lone-wiring-harness-t56-or-non-electric-trans

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It is a good deal. I actually decided to convert my own harness. I will probably have $60-80 and 10-20 hours into customizing it for the application by the time it is said and done. That being said it is all customized to the P59 run L31 it will be running with an aftermarket intake manifold and EV1 injectors. I did some custom stuff like PCM controlling the AD244 as well. That harness would have required modifications anyway for what I am running with it.