86 K10-Orion

[toomany]

Another full day in the shop. Didn't get nearly as much accomplished as I would have liked.

Started by wiring up the interior lighting circuit. First I wired it up as the factory had it, then I tried adding the RAP module (it kicks the lights on at key off, fades them out, uses door switches to kill accessories). For some reason I couldn't wrap my head around how it was supposed to be wired. The digram isn't the best and they don't really explain what is needed for it to function correctly. Apparently I'm not the only one who has struggled with this because Google had a bunch of links to people with the same questions. Eventually I figured it out. The door switches needed to be taken out of the lighting circuit and tied only into the module, with a new ground wire going from the module to the dome circuit. Once that was figured out, it was easy enough to finish the rest of the wiring for the auto headlights/retained accessory power.

It looks worse than it is in the picture. Still, once everything is in, I'll go back and straighten it out some. Above the fuse block is the "switched power" bus bar. Because the Bp harness handles the fuel pump wiring, I repurposed the EZ's fuel circuit for that... already had a relay and fuse in it. The 3 relays next to the box are what it uses to switch power for the lights and whatever accessories you want. The 4th one is the horn relay.





These are the constant and ground bus bars. The hot one is tied into the stud by the battery and has a Maxi fuse on it. The ground goes directly to the negative battery cable. This was the best spot I could find for them, not really a lot of flat open areas under the dash without drilling into the cowl. All 3 bars have covers the will go on at the end.





To the right of the pedals went the command box for the gauges. It fit pretty well there and gives good access to the terminals. Only about half of the inputs are connected right now. The ones from the PCM (vss, tach, check engine) need to be run into the cab still. I intend to have the 4x4 light, cruise light, and brake warning light all work too.






Didn't get to any of the door wiring like I wanted to. That will be the next project.

 

[toomany]

Door harness are in and locks are wired.

Fished the wires from the doors, through the A-pillars and under the dash. Wasn't nearly as hard as I thought it would be, even with the two extra wires for the window relays. Didn't get the connecting harness that runs behind the dash from door to door, so I had to make my own. Didn't get a door lock relay either but, I was able to snag one from a 97 parts Suburban out in the yard. GM kept the same coloring on the wires so it was an easy addition. Left two extra wires hanging out to tie into the relays from the keyless entry module (relays are needed to convert the negative output to positive).

Window wiring will be next. Then I'll only have the neutral saftey/backup light switch, cigarette lighter, cruise and radio wiring left.

 

[toomany]

Most all of the wiring is finished with the exception of the radio, cigarette lighter and remote start. The remote start wiring is started though.

I was at the point where what was left (tach, brake switch outputs, hvac, etc...) needed to be integrated with the PCM, gauge module or remote start. Some of the circuits were coming from the one module to the other, or to all three. I.E.--The remote start and gauge module needed the tach signal from the PCM. PCM needs +12V from the brake switch when pedal is up for the TCC circuit, remote start needs +12v to shut off engine if key is off and brake is pressed, each one needs the opposite of the other. To achieve this I used a brake switch from a 3rd gen Camaro, but pretty much any mid 80's switch from an auto car w/cruise will work.

HVAC is in and wired up. I understand it's a universal-ish kit, but they could have designed the harness a little better and cut out about 4' of wire. It's wired so that the remote start will trigger it to come on. I think I have some grounds back feeding into that circuit. The light one the control panel comes one with the courtesy lights. It goes off with them as well so I'm not too worried about it.

 

[toomany]

Took a break for a few days on this. Had to work on other people's stuff then went out of town for two days.

With the electrical being close (close enough to fire up) I switched things up by moving on to the exhaust. Well, first I was going to do drive shafts. But the one I wanted to use for the rear has the wrong yoke at the front and the u-joint at the rear is too big. Not as simple as a quick shortening to get that in. Of the 5 front shafts I have, none are close enough that I'd feel comfortable using them. One is close, but it's about 1-1.5" too long. It fits, but once the weight of the truck is on it, there isn't much room for the springs to compress before it bottoms out.


With the exhaust I had a few requirements. No drone, quiet-ish, duals, crossover and tailpipes out the back. The drone and noise level is taken care of with a pair of Magnaflow 18" case mufflers. Little bit quieter than the standard 14" ones. In the past, I haven't had any issue with sound quality running a Magnaflow brand muffler, but if by chance I get some droning, I can probably sneak a resonator in somewhere. Duals and crossover is taken care of with some universal bends and an X-pipe. Speed Engineering has a kit that, for the price is hard to beat. All stainless 2.5" mandrel bent and has a bunch of band clamps. I couldn't justify buying more stainless for the rest of the system... especially when I've got plenty of straight pipe and bends left over from a few other systems I've done. The X-pipe is purely for the sound. Most of the LS motors don't sound that great to me when they have split duals. Crossover smooths out the sound.

Not shown are all of my extra bends and hangers. The two straight sections are regular mild steel.




Started on the passenger side because that is the more difficult. Had an idea where I wanted the X-pipe to land and started building to there.

The reason for the bigger bend right at the begining is because it was almost the perfect angle to start with. It's 2 3/4" and has plenty of clearance around the driveshaft and frame.




Tucked up high. Debated going below the driveshaft or above. After thinking about it I couldn't come up with any reason to go below. The driveshaft that is in there is just to give me an idea of what clearance I'll need.





I'll probably do some kind of heat shield for the fuel line above the X.




That's as far as I got tonight. The drivers side will have to rise up too. But it has quite a bit of room to do it in. Once the pipe passes the shifter and transmission, I'll turn it up then. I'm going to build it with the front two sections as one piece and only use clamps at the collectors and X-pipe. It should come off that way if needed. If not, I'll make some cuts and use a butt or V-band clamp to reconnect them.

 

[toomany]

Did some more on the exhaust today.

Other leg of the front half. Wasn't paying attention when I cut the u-bend in half and didn't get it quite in the middle, then having to shorten each side...it wasn't lining up the best with the other half. Used some scrap pieces to cover the gaps.




In the truck. Runs straight out from the header, past the transmission before it turns up. With the clamps loose, there is enough wiggle room to get each leg loose from the X-pipe. After some miles and heat cycles that might change though.




Tucked it up as high as I could. Driveshaft has plenty of room to slide in and out.




Outlets from the X. The hangers I keep on hand weren't going to work how I wanted. They were just too long for me to use and keep everything tucked up high. New ones should be here tomorrow. For now things are just held in place with straps and bungee cords.




The mufflers are a center in/offset out. They are reversible and I figured I'd have to run them offset in/center out. Happened to work better the other way.










Once the new hangers show up, I'll square the pipes up and tighten down all the clamps. Before I do tailpipes, I'll have to stick the bumper back on...maybe even the box. Not sure if I'm going out under the bumper, at a 45 out the side or 90 out the side.

Put the shift linkage together now that I was done with the exhaust in that area. Had to fiddle with it a little bit to get the detents to all line up. Park, reverse, neutral and drive all hit where they are supposed on the column. Apparently the column I used is from a 3 speed truck because it only goes down into 2nd. Will have to get back into the column to open up the travel on the shifter.

 

[toomany]

Put the hangers on the exhaust.

On the left is the style I keep on hand. The one on the right is more of an OE kind. 3/8 stainless rod. They are way cheaper too. Only 1.99 each at Summit.




Without all the straps holding it up.





There are two hangers on each side. A pair at the X and a pair in front of the mufflers. When I add the tailpipes, I'll add two more behind the mufflers and a pair on the pipes. It's secure enough now for me to move on.


Plan is to fire the motor up Friday. It's technically ready to go now, but I want to do it on a day I have more time. I've got the unneeded stuff taken off of the factory tune, just need to load it back into the PCM. The tune up is still factory, it should start and run with that. Once it's driving, then I can worry about getting it dialed in.

 

[jekquistk5]

Put the hangers on the exhaust.

On the left is the style I keep on hand. The one on the right is more of an OE kind. 3/8 stainless rod. They are way cheaper too. Only 1.99 each at Summit.

View attachment 317738


Without all the straps holding it up.

View attachment 317739

View attachment 317740

There are two hangers on each side. A pair at the X and a pair in front of the mufflers. When I add the tailpipes, I'll add two more behind the mufflers and a pair on the pipes. It's secure enough now for me to move on.


Plan is to fire the motor up Friday. It's technically ready to go now, but I want to do it on a day I have more time. I've got the unneeded stuff taken off of the factory tune, just need to load it back into the PCM. The tune up is still factory, it should start and run with that. Once it's driving, then I can worry about getting it dialed in.

Id be interested in your logs/tune as I am still learning and like to tinker. You will probably have to add about 10-15% to your airflow otherwise you will be pedaling to keep it alive.

 

[toomany]

It runs.

Got out of work around 11 and decided I'd see if I could get it to fire up. Loaded the base tune into the PCM, hit the key and all I got was cranking. Tried it a few more times, it was clear I wasn't getting spark or fuel. I knew I had spark (at one point, because I had test fired it off carb clean when I put the harness on), so I looked to the injectors. Probing them with a test light, I was getting signal from the PCM, so I had fuel. Checking for spark, there was none. Traced it back to a blown fuse at the fuse block. It was the one wired in for the sensors, which is odd because I was still seeing crank signal, water temp, throttle position, ect on the scan tool. Hit the key again and it fired up instantly. Settled into a nice 700 rpm idle. Let it warm up while I topped off the coolant and transmission fluid. Going to let it sit till tomorrow before I go back out and check for leaks and levels again.

 

[toomany]

Id be interested in your logs/tune as I am still learning and like to tinker. You will probably have to add about 10-15% to your airflow otherwise you will be pedaling to keep it alive.

It'll be a little bit before I get any seat time to dial it in. Still need to sort out rear driveshaft and install the rear brakes. Once those are in, it'll be able to drive.

Currently it's running off of a factory 4.8 tune. The truck I pulled the 5.3 from was originally a base 4.8 work truck. My cousin and I swapped the 5.3 in after he got it. He was supposed to get it tuned for the 5.3, but never did. Only things I've done to the file so far are pull out VATS, tach signal and remove EVAP/rear o2's.

It idles like I think it should for this cam. Seems a little rich if anything, judging by how my eyes felt before I opened the doors. I'm sure once I get a load on it I'll need to add across the board.

 

[toomany]

Shortened one of the front shafts I've got. Had to take a little over an inch out. It would have worked the way it was, but would have only had a little bit of up travel before bottoming the shaft out.

Took care of a leak at one of the transmission quick connect fittings. Not sure if I didn't have it snapped in all the way or what, but I had a fairly steady drip when running. New fitting and had a nice click when I pushed it in.

Monday I'm going to go get a rear shaft made. I've got enough parts to put one together, but I'd have to cannibalize 3 shafts to make it. And I don't trust myself to get it 100% straight doing that. The front shaft I just did has a little run out, should be fine from what I've seen others look like going down the road.

Rear brake parts should be in early next week. Already have calipers and mounts. Waiting on rotors and lines.

Cleaned up the tune and finalized the basics. Tire size, gear ratio, all emissions codes, fuel codes. No check engine lights come on unless it's a problem one of the necessary systems. This will be my new base file that I'll use to start tuning from.

While I'm waiting for the driveshaft, I'll put the rear bumper on and finish the exhaust. Might try sticking the seat back in so I can get the throttle pedal done (didn't want to do this without the seat in). I don't plan on using the stock bench, but it'll work for the time being.

 

[toomany]

Put the rear bumper on. Not my first choice, but it came with the truck and helps cover the gas tank. I think this style belongs on a long bed or crew cab. Will need to set the box on before I can fully tighten it down.





Measured for the drive shaft. Stuck a bunch of weight on the end to compress the springs some.





I had plans of working on the exhaust, but decided to do some "clean" work instead. Wired in the remote start. Went fairly quick as I had accounted for the necessary wires when I was in the harness. Need to pick up two relays for the door locks. Those harnesses are built and test out correctly though. If I have time tomorrow, I'll install the HVAC ducts and I should be good to put the dash pad on.

 

[toomany]

Went to the driveshaft place around noon and got a phone call at 2 saying it was ready. Brought them my slip yoke and told them the center/center. 3.5x.083 tubing with new end yokes and Spicer 1350 joints. $275 out the door balanced. Which wasn't too bad I didn't think. Had to get new U-bolts for the rear axle. I've never seen a 14bff yoke that takes U-bolts, but mine doesn't have any threads in it and the straps I have don't contact the yoke when the joint is installed.

 

[toomany]

Didn't get nearly as much time in this today as I wanted. Had to go work on my cousins truck so he could use it this weekend. But, I did get the rear brakes installed.

Standard 14bolt disc brake conversion. Used the stock calipers and pads from the old front axle as they were brand new. Square body 3/4 ton front rotors. Hoses from a 2wd GMT400 truck.

Picked up some eBay special brackets for like $30 awhile back. They seemed nice. 3/8" material, grade 8 bolts. Did have to open up the space a little for the calipers to clear. I won't fault the brackets for that though.




The newer hoses actually work better on the rear than the front. Used the bracket on the line to attach them to the spring plates, then some tabs to hold the ends. They clear the springs fine and allow for plenty of caliper movement.





For the drop down hose, I'll reuse the factory bracket and move it so it clears the fuel tank, lines and exhaust. Once that is on, I can finish plumbing the rear section.

Also topped off the transfer case, rear axle and transmission. Except for the brake system (and AC, but that is only half there) all the fluids are good to go.

 

[toomany]

Finished off the brakes, except for bleeding them. They are gravity bled, but I'm sure there is still air in there.




Put the wideband in, which basically had me take the entire exhaust off to weld the bung in. I didn't need to, but decided to weld the reducers to the pipes to get ride of the second clamp there. Wideband sensor is in the drivers side pipe, a couple inches behind the factory O2 sensor. While I had the passenger side pipe off, I put another bung in that one and capped it.

Started truck up and the gauge was reading correctly, but I wasn't seeing anything in HpTuners except for fluctuations between .00v and .02v on the AC pressure input. Digging into it, I had the correct voltage coming from the gauge to the PCM (0-5v), so I knew that was wired right. Turns out I looked at the wrong year pinout for my connector and had one of the pins in the wrong spot. After swapping that I was seeing the correct readings. Then it was just doing some math to get HpTuners to read what the gauge said. From there I was able to get the wideband error set up too.


Bad picture because the gauge was moving to fast for the camera. Was reading around 15.08 here. Gauge matches the Dakota Digital dash pretty well. Not sure where I'll end up putting it, but I only plan to have it in while log/tune.

 

[jekquistk5]

Awesome. I’ll probably end up doing the same thing. I ordered a bunch of weatherpack connectors so I can easily connect/ disconnect and move the gauge.

 

[toomany]

Awesome. I’ll probably end up doing the same thing. I ordered a bunch of weatherpack connectors so I can easily connect/ disconnect and move the gauge.

That's how mine is set up. Two Weatherpacks, one for the power/ground and one for the sensor wires to the PCM. My only complaint with the gauge it the 17' of wire they give you to work with. I think the harness from the gauge to the sensor could be 1/4 the length it is and still be good for most any install.

 

[toomany]

Bled the brakes. Had to grind a little bit of the passenger rear caliper, was getting some drips from the line where it seals on the body. Some casting flash was in the way of the line seating all the way.

Might have to gut the stock proportioning valve and/or get an adjustable one. Rear brakes work, but they don't look to be that strong.

Cleaned up some of the wiring under the dash. Everything under there is taken care of other than radio. Should be good to get the seat back in and mount the throttle pedal. Going to see what I can do about getting some glass back in it this week too.

 

[GWeakland620]

Very nice work man!

 

[toomany]

Fiddled with the remote start some tonight. Adjusted the cranking time a little longer and changed the tach signal. It didn't always start on the first try when cold. On the second try it would fire right up. From the factory it was set to .6 seconds of crank. Changed that to 1 second and it starts everytime now.

Very nice work man!

Thanks! Not trying to build the ultimate square body, just something that is functional and presentable while having the features of a modern truck. I was looking for a newer daily driver truck (not everything I do needs the Duramax) and couldn't justify the prices people were asking for garbage. So I took that money and did this with it. I've had some of the big parts around for awhile and needed to do something with them. The truck just happened to fall into my lap at the right time.

 

[toomany]

Wrapped up the loose ends under the dash yesterday, then set the dash pad and gauge bezel on. Both will have to come back off again though.

The dash pad has seen better days, cracked and stained...but it will do for now. The gauge bezel, I've got like 10 to choose from, some AC some non. The one I wanted to use didn't have the cut out for the wiper switch and the light switch was raised up. Had to settle for the next best one. It's got a rectangular opening between the two main gauges that I don't need, will find a way to plug that I think.




Glass guy came today. Had every intention on reusing the old windshield, but it cracked when I was cleaning it to install it. New one dropped in place real easy with the old gasket. After he left I put the rear window in. Not a fan of the stickers that are on it and will be pulling those off.





Moved on to the seat next. The old one was in decent shape for what it was. Drivers side foam was a little broken down, but the springs didn't sag any.




The springs didn't sag any because they weren't there anymore. At one point they were replaced with what looks to have been a fence. There are two layers running perpendicular to each other. I wondered why it was stupid heavy when I pulled it out.




I'm a firm believer that single cab trucks need a bench seat in them. I've also grown accustomed to having and arm rest on the right side. To satisfy both of those requirements, I pulled the bench out of a 97ish Suburban that I picked up some time back.

Don't know if it is the base model bench or not. It has the fold down counsel and inflatable lumbar on both sides. Has a few burn marks and is dirty, should clean up ok though.

Built a frame on top of the old bench seat sliders. The front of the seats aren't mounted yet. Think I'm going to angle them up a hair before finalizing that. I may even raise the whole thing up some too. It feels alright sitting in it and the distance to the window feels about right too.