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Re: 1986 J20 LS Swap
Posted: Thu Feb 03, 2022 6:34 am
by SJohn
rocklaurence wrote:Wow, you are making a lot of progress. Is the trans a 4L60E? Regarding the rear brakes, will the piston have enough travel to compensate for the spacer? You are coming up with unique ideas--love it
Yes the new trans is a built 4l60e, I pondered upgrading to a 4l80e but I would have spent double the cost reworking everything I had already done.
For the parking brake, yes the piston travel should be enough. As long as the spacer is the right width I will maintain the same distance between the pads and rotor as the original application. All the piston has to travel is that distance between each pad and the rotor at "off" pisition.
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Re: 1986 J20 LS Swap
Posted: Tue Feb 08, 2022 4:44 pm
by SJohn
SJohn wrote: ↑Wed Feb 02, 2022 9:47 am
mike472 wrote:hello, I'm working on my ls swap into 72 J4000, I have so many questions, what size fuel tank did you use?, it looks like from the pictures it hangs a little low, could it have gone up any?, do you have any pictures of the classic auto air install I can stare at, and where/what type of vents are you using? Thank you for all the pics and video clips, sounds sweet!!
Apologies for the delayed response, I haven't checked back here in a while. The fuel tank is a 20gal blazer tank and it looks like it hangs lower than the wagoneer and cherokee pictures I have seen. It is mounted as high as I could get it with the top of the tank touching the lower bed supports. I am in the process of falling up the rear bumper and it hides the tank pretty well.
I just got the AC charged and hooked the vents up this week! I will take some pictures and post them.
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Here are pictures of the AC installed. I used studs instead of bolts to mount the unit to the firewall and used nylon spacers to get it off the firewall half an inch. I also installed a heater bypass to keep coolant flowing through the engine while the heater valve is closed. This was recommended on the LS1TECH forum for LS engines. I installed a Deutsch firewall connector for the compressor and pressure switch wiring. Installing the Deutsch connector makes me wish I would have used them instead of the weatherpack connectors on the rest of the truck. They seem far superior but of course cost way more. Anyways, for vents I went with the universal rectangle vents supplied that came in the kit. I used the original AC line hole for the heater hoses and removed the blank to the left of it and ran the AC lines through it. I made new grommets from the original AC Line bulkhead grommets and 1/8" rubber sheet. The condensation drain is routed to a hole just below the fresh air vent which drains out the same hole as the cowl.
Re: 1986 J20 LS Swap
Posted: Sat Mar 19, 2022 10:57 pm
by mike472
Thank you for the updates, looking at the stock tank I think the blazer tank doesnt hang much lower, the bumper does cover most of it, nice work on the bumper by the way, looks like it belongs there. Also thanks for the tip on the heater valve gotta check the ls site out, glad you got the a/c working, sorry about the garage space, I havent got much more and these trucks are so long
Re: 1986 J20 LS Swap
Posted: Sun Mar 20, 2022 7:37 pm
by SJohn
Welp, I decided that I will be attending the FSJ Ouray invasion this summer and booked my stay so now I have a long list of items to knock out before I try to drive this thing a couple thousand miles.
So Ive been working on swapping in some J10 springs from one of the donor trucks to get a better ride. I cleaned them all up and replaced the bushings with new poly bushings. I've got the front in and it looks like they might have been lift springs as I gained a couple inches of lift. New sway bar bushings are in and steering stabilizer is on the work bench! The steering has a small amount of slop in it so I definitely plan to address the rest of the steering components and firm it up a bit.
One of the most important things I wanted to tackle before driving this thing any long distance was cruise control. With the DBW throttle getting the cruise to work was easy. Something to note is that the factory Jeep cruise control switch is a normally closed contact where as the GM cruise requires a normally open switch. I found that the drawings for 86 Jtrucks and Wagoneers incorrectly shows the switch to be normally open upon verifying with the multimeter. Fortunately for us that have 85+ trucks the turn stalk is a direct swap with early model XJs (1993) with the correct contacts and no disassembly of the column is required. The stalk pulls directly out of the column and the cruise wiring can be fished down the column case. I now have functioning cruise control and the wiper controls were not affected. Also the LS PCM requires a resistance to ground through the brake lights when the pedal is not pressed. Since I have swapped my tail lights to LED this will not work so I added in a small hidden incandescent lamp behind the left tail light to provide this.
Progress on the parking brakes continues; I have 3d printed some brackets and confirmed this is going to work. I am working to get the brackets cut out of 1/4" steel and a coworker is going to mill the spacer out of aluminum. Next will be figuring out the cables.
Re: 1986 J20 LS Swap
Posted: Sun Mar 20, 2022 7:58 pm
by Yeller
Making plans myself, hopefully get to meet you in person there
Re: 1986 J20 LS Swap
Posted: Mon Mar 21, 2022 4:17 pm
by SJohn
Rainy day project while I was off from work today was starting the roof insulation. The headliner in this truck is almost immaculate and one of the first things I noticed when I bought it so I was extremely careful not to damage it. Put in the remaining 80 Mil Noico sound deadener from the floors and what a difference it makes! No more tin can! Next will be closed cell foam and then on to the doors to finish off the insulation.
Re: 1986 J20 LS Swap
Posted: Mon Mar 21, 2022 4:51 pm
by 80Limited
One of the most important things I wanted to tackle before driving this thing any long distance was cruise control. With the DBW throttle getting the cruise to work was easy. Something to note is that the factory Jeep cruise control switch is a normally closed contact where as the GM cruise requires a normally open switch. I found that the drawings for 86 Jtrucks and Wagoneers incorrectly shows the switch to be normally open upon verifying with the multimeter. Fortunately for us that have 85+ trucks the turn stalk is a direct swap with early model XJs (1993) with the correct contacts and no disassembly of the column is required. The stalk pulls directly out of the column and the cruise wiring can be fished down the column case. I now have functioning cruise control and the wiper controls were not affected. Also the LS PCM requires a resistance to ground through the brake lights when the pedal is not pressed. Since I have swapped my tail lights to LED this will not work so I added in a small hidden incandescent lamp behind the left tail light to provide this.
I still need to hook up the cruise in mine. I have an 03 DBW 5.3 in my 87. Did you have to hook up relays or just corresponding cruise wires to the tac module? I did that noico in the whole interior of mine and put the red foam on the door cards and in the quarter panels. Works pretty nice.
Re: 1986 J20 LS Swap
Posted: Mon Mar 21, 2022 4:53 pm
by 80Limited
I still need to hook up the cruise in mine. I have an 03 DBW 5.3 in my 87. Did you have to hook up relays or just corresponding cruise wires to the tac module? I did that noico in the whole interior of mine and put the red foam on the door cards and in the quarter panels. Works pretty nice.
Re: 1986 J20 LS Swap
Posted: Mon Mar 21, 2022 5:16 pm
by SJohn
80Limited wrote: ↑Mon Mar 21, 2022 4:53 pm
I still need to hook up the cruise in mine. I have an 03 DBW 5.3 in my 87. Did you have to hook up relays or just corresponding cruise wires to the tac module? I did that noico in the whole interior of mine and put the red foam on the door cards and in the quarter panels. Works pretty nice.
No relays, swapping in the XJ switch avoids the complicated relay solution that I believe you are referring to. All you have to do is tap into the tac harness. Pin 4 - Set/Coast, Pin 5 - Resume/Accelerate, Pin 6 - Stop Lamp, Pin 14 - Cruise ON. On the XJ switch: Blue - 12V, Red - Set/Coast, Green - ON, Yellow - Resume/Accelerate. Of course confirm the switch circuit first with a multimeter first.
Re: 1986 J20 LS Swap
Posted: Wed Mar 23, 2022 3:36 pm
by SJohn
Here is a wiring diagram I whipped up of the new cruise control wiring in my truck.
Re: 1986 J20 LS Swap
Posted: Wed Mar 23, 2022 5:23 pm
by 80Limited
SJohn wrote: ↑Wed Mar 23, 2022 3:36 pm
Here is a wiring diagram I whipped up of the new cruise control wiring in my truck.
Perfect, that’s kinda what I was thinking. Glad you clarified it. Thanks
Re: 1986 J20 LS Swap
Posted: Fri Mar 25, 2022 11:41 am
by SJohn
The custom brackets are in for the parking brake caliper. Sam at Flying Iron Fabrication took my drawings and cut these out of 1/4" steel for me. These will be welded together after the caliper is positioned how I like and the bolts are tightened up.
Re: 1986 J20 LS Swap
Posted: Fri Mar 25, 2022 1:49 pm
by Yeller
I’m really curious to the effective strength of this once you are done.
Re: 1986 J20 LS Swap
Posted: Wed Mar 30, 2022 1:06 pm
by Txrangers20
I noticed a while ago that you had a J20 for parts. Do you still have the tailgate by any chance? I have been struggling trying to find one.
Re: 1986 J20 LS Swap
Posted: Wed Mar 30, 2022 2:06 pm
by teking
Last time I left something like that in the yard I slept on the couch.
She said the handgun range I installed was my last free pass.
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Re: 1986 J20 LS Swap
Posted: Wed Mar 30, 2022 2:11 pm
by SJohn
Txrangers20 wrote:I noticed a while ago that you had a J20 for parts. Do you still have the tailgate by any chance? I have been struggling trying to find one.
All of my parts trucks are gone, I've sold it all!
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Re: 1986 J20 LS Swap
Posted: Wed Mar 30, 2022 2:15 pm
by SJohn
teking wrote:Last time I left something like that in the yard I slept on the couch.
She said the handgun range I installed was my last free pass.
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Hahaha my dad's backyard looked like a junkyard the past 2 years but as of a couple months ago all of the trucks are gone. He doesn't mind, he's the one regularly sending me marketplace ads
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Re: 1986 J20 LS Swap
Posted: Thu Mar 31, 2022 6:36 pm
by SJohn
Re: 1986 J20 LS Swap
Posted: Sun Apr 10, 2022 6:18 pm
by SJohn
Tackled some small projects and started some bigger ones the last few weeks. Starting new projects is the opposite of what I need to be doing but I got it stuck in my head and had to do it.
I seem to never stop working on the wiring for this truck. The most recent project was adding a Deutsch firewall connector for the cruise control, throttle pedal, and gauge wiring. No more wires going through the firewall without a bulkhead connector now! If I could go back a year ago when I was working on the wiring harness on the kitchen table I would slap myself and tell me to do it all with Deutsch connectors. They are more expensive but far better in my opinion than weatherpack connectors. The pins are rated for higher amps, the seals are built into the connector rather than an individual seal per wire, and the connections are way better. I know I have said all this before but every time I work with these connectors I love them more! I still have some more work to do hiding the few loose wires left but this cleaned up the firewall alot!
The auxiliary fuel tank is plumbed in and operational sub a fuel gauge. I used a cheap amazon transfer tank filler tee that ties directly into the 2" fill line at the rear tank and a cheap frame mounted fuel pump to transfer the gas. From the first tests it looks like it will take 30 to 45 min to fill the rear tank via transfer pump.
Finally, the big project I decided to start on a whim, a camper top for the Jeep! Seeing as there's no room for luggage in the cab and wet clothes doesn't seem like a fun time, I figured I was going to need something to keep my stuff dry and safe when I actually drive this thing a decent distance. So I went on the hunt for a camper for my truck and of course it wasn't a simple task to find anything that would fit my truck. Thanks Jeep for making a truck bed narrower than full size trucks but longer than midsize trucks (for those of us with 8' beds). So I figured if I could find an aluminum camper that was the same length I could just cut it in half and stitch it back together to fit. So I did it! I picked up a cheap camper off an 03 superduty that measured 73" wide by 99" long (an inch longer than the Jeep but I can handle that without cutting). The Jeep bedrails measure 62.5 by 98 inches. I used some 2x4s and whole lotta ratchet straps to get it home. These things are super easy to dismantle, they're put together with self tapping screws. Once the ends and top were skinned I cut 10.5 inches from the middle and stitched it back together with 1/8th" aluminum flatbar and rivets. Once everything is stitched back together Ill weld it up with my dads mig spool gun to really hold it all together. For the windows I can either replace them with plexiglass or have the glass cut down. Here's pics
Re: 1986 J20 LS Swap
Posted: Thu May 05, 2022 8:14 pm
by SJohn