Author Topic: 99 5.3L swap in a 86 k20  (Read 5352 times)

Offline 86k20

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99 5.3L swap in a 86 k20
« on: January 11, 2011, 02:39:08 pm »
has anyone tired to cut the factory harness to adapt in older trucks if so how hard was it i was on lt1swaps site it doesnt look that bad just want to here some feedback if you did it yourself. i dont want to spend the 1000$ for a custom harness so i want to go cheep i can do it i think

Offline lechez71

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Re: 99 5.3L swap in a 86 k20
« Reply #1 on: January 11, 2011, 02:48:50 pm »
no need to spend $1000 for a harness. you can send yours to get reworked for $450. IMO its worth it dont want to risk frying a pcm, and saves you alot of headaches.

Offline Captkaos

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Re: 99 5.3L swap in a 86 k20
« Reply #2 on: January 11, 2011, 03:23:04 pm »
I have one I am going to rework, but I bought a Painless for one truck it was only $550 at the time, and it was all new wiring.

Offline 86k20

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Re: 99 5.3L swap in a 86 k20
« Reply #3 on: January 11, 2011, 03:23:56 pm »
now what about modifing the frame for the manifolds to clear and the timing cover i was told it would bolt in but after doing some searching i found out that i had to do that

Offline lechez71

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Re: 99 5.3L swap in a 86 k20
« Reply #4 on: January 11, 2011, 04:30:37 pm »
i didnt have to trim any of the frame to fit the manifolds, i used the ones from a 07 envoy denali. i dont quite understand what you r talking about the timing cover.

Offline Captkaos

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Re: 99 5.3L swap in a 86 k20
« Reply #5 on: January 11, 2011, 04:35:40 pm »
I used headers so I don't have a frame problem.  Timing cover doesn't hit.  I also was going to us 02 Truck manifolds and removed the EGR fittings and they fit also.

Offline 86k20

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Re: 99 5.3L swap in a 86 k20
« Reply #6 on: January 11, 2011, 05:11:54 pm »
ok well i guess im going to buy the motor for 350$ comes with harness computer and y pipe with cats

Offline lechez71

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Re: 99 5.3L swap in a 86 k20
« Reply #7 on: January 11, 2011, 05:18:22 pm »
it good to get a complete motor beacuae youll spend lots of money searching and buying parts.

Offline lechez71

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Re: 99 5.3L swap in a 86 k20
« Reply #8 on: January 11, 2011, 05:21:22 pm »
i hope you do some research before you start swaping so you wont be lost during the swap. gonna need the pem programmed, need a electric fuel pump, motor adapter plates.

Offline 86k20

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Re: 99 5.3L swap in a 86 k20
« Reply #9 on: January 13, 2011, 05:37:52 pm »
i have a pcm that has been burned with all the essentials and motor mount adapters i need to get the trans adapter but im still in the air if i want to keep the th400 or go with the 4l80e i like the over drive option but i dont want to make more drive shafts so does anyone know if the 80e and the th400 are the same overall length