1986 J20 LS Swap

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SJohn
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Re: 1986 J20 LS Swap

Post by SJohn »

Here's the rebuilt shock tower.
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1986 J20 LS Swap
https://www.fsjnetwork.com/forum/viewto ... 12&t=17875

1981 Cherokee Chief - Rustard - 2JZ swap
https://www.fsjnetwork.com/forum/viewto ... 12&t=22981

81waggy
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Re: 1986 J20 LS Swap

Post by 81waggy »

I used http://newvintageusallc.mybigcommerce.c ... ual-black/

Work well and have a more vintage jeep look. Everything you need is in the box...ie wires, sensors, adapters. The only issue I have is that the fuel gauge reads backwards.

You have to trim a little to get them to fit into your cluster and wire up turn signal indicators. They have indicators installed, but they're pretty dim.
81 Wagoneer with a TBI 350 Vortec.
83 Wagoneer - 360 Quadratrac
69 Wagoneer - 350 Diesel trail rig
70 Wagoneer - 1414x

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SJohn
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Re: 1986 J20 LS Swap

Post by SJohn »

Update: I removed the cab to make fabbing the crossmember and plumbing easier, bolted the engine up with BJ's Offroad LS engine mounts, and had the harness rebuilt by Easy EFI Solutions! Next task is to unbolt the trans to put in a new rear main seal and replace cam position sensor and oil pressure sensor while they are easily accessible.
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Owner/Operator/Chief Engineer of Johnson Production FSJ Parts
https://www.johnsonproductionjp.com/

1986 J20 LS Swap
https://www.fsjnetwork.com/forum/viewto ... 12&t=17875

1981 Cherokee Chief - Rustard - 2JZ swap
https://www.fsjnetwork.com/forum/viewto ... 12&t=22981

Scott2
Posts: 11
Joined: Sat Sep 22, 2018 8:15 am
Location: Colorado front range

Re: 1986 J20 LS Swap

Post by Scott2 »

Nice looking J20 and should be a great driver when you’re done. What have you figured out for the gas tank? I’m swapping a Tahoe 5.3/4L60e into my ‘79 J10 and want to keep both the stock tank location and use the Tahoe pump with fuel level and pressure sensors plus the vapor cannister to keep the emissions police happy.

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SJohn
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Re: 1986 J20 LS Swap

Post by SJohn »

Scott2 wrote:Nice looking J20 and should be a great driver when you’re done. What have you figured out for the gas tank? I’m swapping a Tahoe 5.3/4L60e into my ‘79 J10 and want to keep both the stock tank location and use the Tahoe pump with fuel level and pressure sensors plus the vapor cannister to keep the emissions police happy.
Thanks! I haven't found a tank that would retain the sending unit from the donor and I'm leaning towards adding an in tank pump to the factory sending unit and keeping the factory tank. The only issue I fear I'll have with modifying the factory sender is fuel starvation due to the lack of baffles inside the original tank. I don't think there is any other tank that will accept the silverado/tahoe/suburban etc sending unit but if you find one let me know.

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Owner/Operator/Chief Engineer of Johnson Production FSJ Parts
https://www.johnsonproductionjp.com/

1986 J20 LS Swap
https://www.fsjnetwork.com/forum/viewto ... 12&t=17875

1981 Cherokee Chief - Rustard - 2JZ swap
https://www.fsjnetwork.com/forum/viewto ... 12&t=22981

sonoraed
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Re: 1986 J20 LS Swap

Post by sonoraed »

I'm at home and don't have details, just installed a 2001 K1500 fuel module in a 58 nomad with 3-2 Fitech fuel injection, used the GM style because of the the antislosh design, used the mounting rings for a Hyperfuel 40019 intank pump had to shorten the three legs for height, used the stock fuel filter which is a combo filter/return/regulator, there is YouTube showing guy installing this module in a Camaro.
In my 79 J10 / LM7 used a 99 Suburban tank behind the rear axle, had to move the crossmember forward a few inch's works good love the LM engine runs so good!!
BTW Wahlbro makes a stock GM module that has more fuel volumne.

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SJohn
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Re: 1986 J20 LS Swap

Post by SJohn »

Update: New rear main seal, cam position sensor, oil pressure sensor, transmission filter and starter solenoid installed and buttoned the transmission all back together. Next step is to modify the crossmember. I decide to modify the stock sending unit with an in tank fuel pump (ep381) so I soldered a 3/8 line for the pickup and will use the original pickup for the return. The silver solder from the hardware store does not stick at all to this metal so I had to pick some up from a local welding supply shop which worked great and even costs less! I'm still trying to find out how to run the fuel pump wires through the sending unit so any suggestions are appreciated.
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Owner/Operator/Chief Engineer of Johnson Production FSJ Parts
https://www.johnsonproductionjp.com/

1986 J20 LS Swap
https://www.fsjnetwork.com/forum/viewto ... 12&t=17875

1981 Cherokee Chief - Rustard - 2JZ swap
https://www.fsjnetwork.com/forum/viewto ... 12&t=22981
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hutcho
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Re: 1986 J20 LS Swap

Post by hutcho »

Good looking swap you got going so far!!

Unrelated to the Jeep, but are the mirrors power off your donor, and if so would you wanna sell them?

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SJohn
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Re: 1986 J20 LS Swap

Post by SJohn »

hutcho wrote:Good looking swap you got going so far!!

Unrelated to the Jeep, but are the mirrors power off your donor, and if so would you wanna sell them? Image

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Thank you!
The mirrors are powered and are for sale, along with the other remaining pieces! DM me!

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Owner/Operator/Chief Engineer of Johnson Production FSJ Parts
https://www.johnsonproductionjp.com/

1986 J20 LS Swap
https://www.fsjnetwork.com/forum/viewto ... 12&t=17875

1981 Cherokee Chief - Rustard - 2JZ swap
https://www.fsjnetwork.com/forum/viewto ... 12&t=22981

Topic author
SJohn
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Re: 1986 J20 LS Swap

Post by SJohn »

Got the transmission mount fabbed up and painted. Also removed two broken manifold bolts from the heads, replaced with stainless arp bolts and remflex gaskets.
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Owner/Operator/Chief Engineer of Johnson Production FSJ Parts
https://www.johnsonproductionjp.com/

1986 J20 LS Swap
https://www.fsjnetwork.com/forum/viewto ... 12&t=17875

1981 Cherokee Chief - Rustard - 2JZ swap
https://www.fsjnetwork.com/forum/viewto ... 12&t=22981

Topic author
SJohn
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Re: 1986 J20 LS Swap

Post by SJohn »

Picked up a NP241c this weekend and mounted it up, anyone know if this is the same clocking position as factory from GM? I ended up cutting the mount I previously built for the crossmember off and bolting the transmission mount flat on the crossmember since I was worried the cab would hit. Also started on the fuel lines.
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Owner/Operator/Chief Engineer of Johnson Production FSJ Parts
https://www.johnsonproductionjp.com/

1986 J20 LS Swap
https://www.fsjnetwork.com/forum/viewto ... 12&t=17875

1981 Cherokee Chief - Rustard - 2JZ swap
https://www.fsjnetwork.com/forum/viewto ... 12&t=22981

Topic author
SJohn
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Re: 1986 J20 LS Swap

Post by SJohn »

After a couple failed attempts at modifying the original sending unit I have spent far more money than expected to make the stock tank work but it should all work in the end. Soon after soldering the fuel line to the original sending unit, the fuel line and sending unit flash rusted horribly including the inside of the fuel line. My second attempt was buying a top mount sending unit that I though already had a 3/8 line in it and modifying it to work with my side mount tank. My thoughts were wrong and now I have a top mount sending unit with factory size fuel lines. So I decided to go ahead and spend a load more money than I ever anticipated on for this part of the project and ordered parts to make my own sending unit. A 2.75" stainless steel disk, and a few AN fittings later I think I'm finally on the right track! Also, AN fittings are STUPID expensive!!! The sending unit alone will cost me more than the rest of the fuel system.
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Owner/Operator/Chief Engineer of Johnson Production FSJ Parts
https://www.johnsonproductionjp.com/

1986 J20 LS Swap
https://www.fsjnetwork.com/forum/viewto ... 12&t=17875

1981 Cherokee Chief - Rustard - 2JZ swap
https://www.fsjnetwork.com/forum/viewto ... 12&t=22981

81waggy
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Re: 1986 J20 LS Swap

Post by 81waggy »

Its probably too late, but I've heard mid 90's trailblazer tanks fit where the spare tire usually goes. With that tank you get the in tank fuel pump and fuel gauge. You'd have to do some searching but I know its somewhere.
81 Wagoneer with a TBI 350 Vortec.
83 Wagoneer - 360 Quadratrac
69 Wagoneer - 350 Diesel trail rig
70 Wagoneer - 1414x

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SJohn
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Re: 1986 J20 LS Swap

Post by SJohn »

81waggy wrote:Its probably too late, but I've heard mid 90's trailblazer tanks fit where the spare tire usually goes. With that tank you get the in tank fuel pump and fuel gauge. You'd have to do some searching but I know its somewhere.
Yes I have seen that this tank is commonly used. I went this route to avoid the cost of a tank, and sending unit/pump on top of the rest fuel system. That might have actually been cheaper now that I've went through multiple attempts but I'm determined to make this work now!

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Owner/Operator/Chief Engineer of Johnson Production FSJ Parts
https://www.johnsonproductionjp.com/

1986 J20 LS Swap
https://www.fsjnetwork.com/forum/viewto ... 12&t=17875

1981 Cherokee Chief - Rustard - 2JZ swap
https://www.fsjnetwork.com/forum/viewto ... 12&t=22981

CU4WHLN
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Location: Michigan

Re: 1986 J20 LS Swap

Post by CU4WHLN »

SJohn wrote: Thu Jan 16, 2020 6:37 pm Update: I removed the cab to make fabbing the crossmember and plumbing easier, bolted the engine up with BJ's Offroad LS engine mounts, and had the harness rebuilt by Easy EFI Solutions! Next task is to unbolt the trans to put in a new rear main seal and replace cam position sensor and oil pressure sensor while they are easily accessible.

Question 1: Which trans and did you have to move the trans cross member back on the frame ? I am assuming this powertrain is longer than stock?

Question 2: Was the wiring rework "reasonable" cost? Did include a flash/program your ECU ?

TIA
It's not YOURS until you BLEED on it !

+ 01 XJ Cream Puff +16 JK Daily Driver + 85 CJ locked and loaded
+ 03 Rubi + 77 Chief 401 + 79 Chero - Madness: Sold

77 Gen V swap http://www.ifsja.org/forums/vb/showthread.php?t=188457
77 401 build: http://www.ifsja.org/forums/vb/showthre ... ief+begins
79 "Madness" build: http://www.ifsja.org/forums/vb/showthre ... ief+begins

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SJohn
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Re: 1986 J20 LS Swap

Post by SJohn »

CU4WHLN wrote:
SJohn wrote: Thu Jan 16, 2020 6:37 pm Update: I removed the cab to make fabbing the crossmember and plumbing easier, bolted the engine up with BJ's Offroad LS engine mounts, and had the harness rebuilt by Easy EFI Solutions! Next task is to unbolt the trans to put in a new rear main seal and replace cam position sensor and oil pressure sensor while they are easily accessible.

Question 1: Which trans and did you have to move the trans cross member back on the frame ? I am assuming this powertrain is longer than stock?

Question 2: Was the wiring rework "reasonable" cost? Did include a flash/program your ECU ?

TIA
Sorry for the late response, I have a 4l60e and did have to move the crossmember back. I haven't measured the drivetrain to compare but it definitely is longer than the stock drivetrain. The wiring rework was right around $500 including ECU programming. This was a reasonable price in my opinion just to avoid the frustration.

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Owner/Operator/Chief Engineer of Johnson Production FSJ Parts
https://www.johnsonproductionjp.com/

1986 J20 LS Swap
https://www.fsjnetwork.com/forum/viewto ... 12&t=17875

1981 Cherokee Chief - Rustard - 2JZ swap
https://www.fsjnetwork.com/forum/viewto ... 12&t=22981

Topic author
SJohn
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Re: 1986 J20 LS Swap

Post by SJohn »

It has been a while since my last update and I have made quite a bit of progress. The fuel sending unit is finished and working besides adding a fuel level. After finishing the fuel sender and plumbing fuel lines and transmission lines I was able to successfully fire up the engine! That gave me a good bit of motivation! The floors are finally done and so far the interior has been painted and sealed. Next is to paint the underside and firewall. Interior parts are piling up; dakota digital gauges, winters shifter, and carpet are waiting for install!
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Owner/Operator/Chief Engineer of Johnson Production FSJ Parts
https://www.johnsonproductionjp.com/

1986 J20 LS Swap
https://www.fsjnetwork.com/forum/viewto ... 12&t=17875

1981 Cherokee Chief - Rustard - 2JZ swap
https://www.fsjnetwork.com/forum/viewto ... 12&t=22981
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Stuka
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Re: 1986 J20 LS Swap

Post by Stuka »

Are you not going to run a heater, or are you going with some other solution?

Good to hear you got it running!
2017 JKU Rubicon
Pevious Jeeps: 1981 J10, 1975 Cherokee, 2008 JK, 2005 KJ, 1989 XJ

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SJohn
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Re: 1986 J20 LS Swap

Post by SJohn »

Stuka wrote:Are you not going to run a heater, or are you going with some other solution?

Good to hear you got it running!
I will be going with the vintage air system

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1986 J20 LS Swap
https://www.fsjnetwork.com/forum/viewto ... 12&t=17875

1981 Cherokee Chief - Rustard - 2JZ swap
https://www.fsjnetwork.com/forum/viewto ... 12&t=22981

dissinnick
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Re: 1986 J20 LS Swap

Post by dissinnick »

keep us posted on the vintage air, ill be doing the same shortly, and am thinking i might try and plumb into the AC system and replace AC controls with Vintage air ones.

cheers! good build thus far.
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