Huck's 85 GMC shorty
 

What's up guys, thought I'd start a build thread on here since I just joined up. I miss forums and am glad there's still a few active ones around. I've got an '85 GMC Sierra Classic I picked up a couple years back and have been slowly building it up. It's not my first C10 or classic but it's been the most fun yet.

My first one was this '85 Blazer I picked up in '14. 350/T350/33s. Drove that through snowmageddon (Georgia lol) and sold it in the spring of '15. Should've kept it, paid $3300 and all it needed was one floor patch and a little repair on the tailgate. Everything worked great and had a fresh crate 350 in it.
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Then my cousin's husband sold me this '70 SWB stepper 6cyl/3OTT for $1 later in 2015. I just did maintenance and drove it that way for a couple years. Got married, bought a house and it had to go to pay some bills :(
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Then got divorced a few years later and decided I needed a project to help keep me sane. Was browsing FB marketplace and saw this two tone blue truck and fell in love immediately. You hardly ever see this color combo and blue is my favorite color so I had to have it. Worn out 305/T350/2.73 combo, PW, PL, cruise (non-functional), tilt, loaded. It was originally a longbed that this guy paid to have cut down, paint spotted in and clearcoated. There was even a hole in the floor (filled with aluminum foil and bondo lol) for a 5th wheel ball. This thing apparently was used to haul horses.
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A buddy of mine found a picture of it, pre-cut, on FB from the shop that did the chop
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Re: Huck's 85 GMC shorty
 

A few more from when I first bought it

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Got tired of the torque thrusts so I sold them and picked up a set of rallies with trim bands, center caps and stock size 235/75/15s
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And picked up a tonneau cover for some extra dry storage
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Then wire brushed and fogged on some GM light blue metallic over where they'd cut the bed and removed the center stake pockets
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It's time to leave work, so I'll continue later on lol

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You’ve had some sweet rides there buddy! Digging the new truck.

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The interior was pretty nice, just needed a good cleaning. Everything worked, windows were slow but functional. Locks worked, AC and heat would run you out, tilt works. The only thing that didn't was the cruise because one of the bellows was torn.
Before:
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After:
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And a shot of the engine bay as purchased:
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So I bought this truck with the intention of LS swapping it. I'd become good friends with the guys from United by Trucks and the local C/10 Club of Ga and several of them had LS swapped trucks. My now good buddy Ron (Two Trucks Ron if y'all follow UBT) had a 5.3/4L60/3.73 '84 at the time and followed me up to a car show in Greenville, TN. He told me "I'll follow you cuz I know what it's like for a small block to keep up with an LS" :lol: Needless to say, after it would barely hold 35mph up the mtn, the swap got serious after that.

Started collecting all the parts I'd need that could work for any engine combo since I hadn't picked one up yet:
-Tejas Steelworks engine mounts, trans mount and fan shroud for dual 13" fans
-'87 fuelie tank from work (Auto Metal Direct)
-Spectra '87 fuelie sending unit
-AC Delco EP381 pump
-Vincos DIY AN line kit from Amazon (2 of them, for fuel and trans lines)
-Spal 13" fans (the middle of the road CFM rating since the top dogs were $100 more each)
-Speed Engineering 1 3/4" headers with their plug wires



We have a friend/customer of ours that runs a local junkyard so I went to see him one Saturday to see what he had for LS motors and came home with this out of his personal project stash. It's an '06 LH6 out of an Envoy Denali with 104k miles on it. These are an aluminum gen4 block and rods, flat top pistons, 799 heads, 10:1 compression and a TBSS style intake. That with a 4L65E and the E40 computer. They're rated for ~320-335hp depending on your source :metal: I had already stripped the mechanical fan/accessories/manifolds off and washed it at this point. **edit** IDK why it rotates some of my pictures :facepalm:
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Since I had the motor, the next round of parts was ordered:
-BTR Stage 4 V2 truck cam
-LS6 valve springs
-Chromoly stock length pushrods
-new valve stem seals
-valve spring tool
-lapping compound
-cam handle
-timing set
-half a set of lifters to get rid of the DOD
-Circle D 3000 stall converter
-PSI Conversions wiring harness

Once the cam stuff came in, I started the teardown on the engine. No shock, it was clean as can be. The bottom end rotated like butter so we didn't go any further, just rebuilt the top end, threw the cam in and reassembled it.
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Freshly assembled head
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Cam in and everything coated in assembly lube
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Taped up and primed
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First layer of Chevy red-orange
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Had to throw everything on it to see the final product! :bann:
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Re: Huck's 85 GMC shorty
 

Thanks! I've had a bunch of cars and trucks over the years but these old Chevy trucks are my favorites

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That's a well-kept truck. Glad you are having a good time with it.

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So now that the engine was finished up, time to yank the hurt 305

Hood off, starting disassembly
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Removed most anything that would get in the way/wasn't going to need
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Mid pull
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All out! Nasty ole lump in the corner of the shop (it's still there, 1.5yrs later lol)
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Pushed the truck out to the edge of the shop to clean/degrease the engine bay
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The bay really wasn't horrible, I've certainly seen worse
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All clean
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Back in the corner with some of the aftermath lol
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Fresh coat of paint
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Then up on cribbing to start painting the frame/Raptor lining the underside of the cab
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Then I grabbed some various wire brushes to use in a drill to start wire wheeling the bottom of the cab clean. I knew this truck was solid when I bought it but man, not a SINGLE SPEC of rust anywhere, just dirt. I was blown away at how clean the inner rockers/inner cab corners were. Working at AMD, I constantly see squares with no rockers or cab corners left so this was a major win :bann:

These are looking at the passenger side inner rocker from the middle of the truck. Front of the truck is to the left.
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Then started applying the Raptor liner. Prepped with a final pass of a red scotchbrite and then a thorough wipe down of wax and grease remover. I used the aerosol cans they sell on Amazon. Took a chance on the blue but it was nowhere close to either of my colors. Oh well :dohh: It looks great underneath, even if it doesn't match.
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This shot is looking forward along the passenger side
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Then grabbed some VHT Chassis Black for the rails. I'm impressed with this stuff, laid down nice and dried to a nice sheen, not too shiny at all.
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Very nice.

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Bump

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Work and life have gotten crazy lately, haven't had a chance to update but I'll pick it up now.

So next was prepping the motor to drop it in. Pulled the front drive back off, filled the converter and got it all married up
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First try
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Turns out the Envoy PS reservoir was hitting the frame rail, keeping the motor from dropping all the way in
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Pulled that off for now and got 'er set in
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So much room with the TBSS/Envoy A/C compressor setup!
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Ok, serious question. Does anyone know why pictures keep being uploaded sideways? This is the only forum it does it on. I've uploaded these same pictures elsewhere with no issue

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From what I understand, you want to shoot your photos landscape with the bottom of the phone to the right. You might PM a moderator and see if they can fix your photos. I'll see if I can repost the most recent five. You can probably do what I did and that is save the photos off the thread as posted, go into edit and spin them as needed and repost them. For whatever reason when you do that before posting them it doesn't seem to take. But all I did is save your photos to my phone, twist them, resave them on my phone, and then repost them and then delete them from my phone.

Re: Huck's 85 GMC shorty
 

Sorry for dropping off the face of the earth guys. I somehow got logged off after that last post in June of '22 and couldn't get back in to save my life. Eventually gave up on it. Somebody sent me a link to check out on here and I just randomly tried again yesterday and managed to get in! Idk what happened but I guess I'll continue on with the build thread lol. There's been quite a few exciting new changes since my last post :bann:

Re: Huck's 85 GMC shorty
 

So the next thing to do was wiring...I hate wiring. I can run a harness no problem but tracing issues and combining original wiring with swap wiring is where I struggle. But with some help from my tuner buddy, I slowly got it all done. Ran the harness through the factory ESC hole and mounted the computer above the HVAC box. Also got my Tejas fan shroud set up and installed so I could tie that wiring in while I'm at it.

Re: Huck's 85 GMC shorty
 

I'd also been getting parts in for the rear axle rebuild around that time. I ordered everything through Quick Performance. They have a killer package for the diff - it comes with all the bearings and seals, a Yukon Dura-Grip clutch style locker and your choice of spline count and ratio with Richmond Gears. I upgraded to the 30-spline and chose 3.90 gears. Also grabbed their matching axles, a T/A girdle cover and a 1350 yoke while I was at it.

Re: Huck's 85 GMC shorty
 

I'm diggin it!

Re: Huck's 85 GMC shorty
 

So working for AMD and being one of the car show "carnie's" that's always travelling to shows, we have contacts all over. Joe from Squarebody Syndicate had reached out to our marketing manager to see if we'd throw in some sheetmetal for a build he had going on. My marketing guy mentioned my build and Joe told him to tell me to just go order some stuff from his website and I'd get a surprise in the mail. I didn't know what was coming, so I bought a whole bunch of stuff from him and wouldya looky there, he sent some of his Squarebody Syndicate Dakota Digital VHX's for me to try :jdp::D:D

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So I took 'em home and started wiring them up a couple weeks later. They were super simple to wire once I found the master schematic for the gauge plug for these trucks

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Here's those master schematics in case anyone needs them. Might've found them here, can't remember what forum I found them on. If the upload quality sucks and you want a copy, PM me your email and I'll shoot over the high quality version

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I love how these turned out, they look OEM+. I don't mind the regular Dakotas but these just knock it out of the park. Super simple to get set up the way I liked as well

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So at that point, I went up to our local driveshaft shop to see about getting a shaft built. He gave me 2 different yolks to try. Went home, figured out which would work best, took a measurement and gave him the specs of the truck. He build a stout 4" shaft with 1350 joints on either end.

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Then I took a couple pieces of pipe from my Speed Engineering builders kit and clamped them to the headers so we could bust it off and have the rear o2s be happy. We got it to run for about 30sec before the fuel pump died. This would begin a long saga....

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Re: Huck's 85 GMC shorty
 

That was an AC Delco EP381 that my tuner buddy swears by. Couldn't find another, so used a Dephi equivalent to replace it. Did that, loaded the truck in the trailer and took it to C10 Fall Revival in Oakboro, NC for it's unofficial debut in our AMD booth. Busted it off a couple times to listen to the thunder and all seemed good. Brought it back home and back into the shop it went. Had to drag it with the tractor since it still wouldn't drive at all. That turned out to be a bad TCM that wouldn't communicate

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Tinkered with it some more, got the TCM in it and flashed and got a basic start up tune loaded in. Went to pull it out to trailer it to the exhaust shop and it made it ~100yds before it ate another fuel pump :waah: So we winched it in the trailer again and had to push it into the exhaust shop.

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Re: Huck's 85 GMC shorty
 

I feel your frustration....

I did AC Delco pumps for my dually. Ist one failed before it made it out of the parking lot (drivers side tank @ <6wks old). Put a Delphi in its place.

The 2nd AC Delco (pass side tank) failed about 2months later. Luckily it was on my return trip from Conroe & I had the drivers side full to keep me moving.

The Delphi in the drivers tank failed within 2yrs.

For the 3rd round, I bought some Carters based on how the 'go-to' pumps did so well.

Re: Huck's 85 GMC shorty
 

So far, my posts have been catching up to present day. So far, we're still about 3yrs behind. I'm on fuel pump number 5, this one a Walboro. It also has gotten iffy, becoming very loud on my last cross country journey. Aeromotive may be my next step

Re: Huck's 85 GMC shorty
 

So at that point, once the exhaust was done and that fuel pump had died, I pushed the truck into my buddy's shop and didn't touch it again for several months. I had burnt myself out on the truck and needed to regroup.

My tuner kept telling me the Delco pump had to be a fluke and that the Delphi was an inferior pump. So I ordered another Delco, threw it in and trailered the truck down to his shop to start tuning. Well guess what...

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We only got it to fire a couple times, it would idle like crap and then die again. Then wouldn't fire at all. So back in the trailer it goes to get it out of his way. Around this time, my position at work changed and I now have access to our work area in our R&D center. So that's where I took it this time, so I'd have more room to work. Dropped the tank and threw in another Delco. This time, I also wired in a better relay and located it back at the tank. Re-ran a new, heavier gauge wire as well.

I don't know what made me do it, but when I went to change over the sock, I turned it over on my tailgate and wouldn't ya know, pieces came out! The Spectra sending unit I bought came with a sock that had one of those little plastic pieces in it to keep it from sucking in on itself and the plastic had started to come apart. That must've been what's been eating my pumps! So I grabbed one of our AMD senders off the shelf to rob the sock from and threw it all back together.

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FINALLY! I cranked it up and it would idle like it's supposed to and for the first time ever, I actually drove the truck! Only back and forth a few feet but still! That was a huge victory.

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My tuner offered to come to work this time rather than having me trailer it down to him. So I let him do his thing. He worked on it for a little over an hour and said "Man it runs good but it's got a dead miss at idle". Got my temp gun out and sure enough, #1 was cold. Swapped injectors, swapped coils but still nothing. Popped the valve cover off and I'd missed the intake rocker bolt, the rocker was just flopping. D'OH. Torqued that one back down, checked the rest and we finished up WOT tuning at that point.

After all the fuel pump issues, I was very leery at this point to beat on it, worried it might lean out and blow up. So I started daily'ing the truck back and forth to work, slowly getting more comfortable with it.

The guy that travelled with me to shows doing our marketing started harassing me to take it to Battle in Bama that May. That was only a couple weeks away at the time and I only had ~400mi on the truck, I didn't want to take the chance. Well, he finally harassed me enough that I loaded up my entire toolbox and spares and made the trip. 6.5hrs later, it made it with no issues and knocked down 22mpg! I was beyond happy with that.

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Even had to put her to work moving our display around in the soft ground :lol:

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Drove it to and from the show every day that weekend, made it home (10hr trip thanks to traffic) and pulled down 18mpg on the way home. Never turned wrench one. Was a very successful maiden voyage

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Well, I found out that the AC Delco's were 'made in mexico' but the Delphi's were still an OE tier supplier & made in Michigan thus my decision to switch to them.

Once it failed, I figured I'd give Carter a shot. I still haven't done the passenger side tank. It's had 20gals of gas sitting in it for >4yrs now so I bought a whole new tank just to make life easier when I did the work.

Glad your start-up voyages went well for you. Looking forward to more details as you get us caught up.

Re: Huck's 85 GMC shorty
 

I've never heard of Carter fuel pumps, hopefully that works for ya. If this Walboro poops the bed, I'll probably just get an Aeromotive fuel pump module. That would work best with my eventual AutoX goals anyway

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Before the show, I'd been wheel shopping and really liked the look of these US Mag Bullet's. Throughout the weekend though, I saw these on EVERYTHING. Chevelles, S10s, C10s, mini-trucks, newer stuff, EVERYWHERE. So that was a no-go

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Got home and immediately started shopping again. Found the US Mag Roadster and knew that was the one. I grew up helping my dad and his friend work on and race air-cooled 911 Porsches. These wheels kinda have that Fuch's look to them but also fit the truck being a similar color to the original rallies. Plus the rears were available all the way up to a 10.5, so that was nice as well. Got them in and started test fitting

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You can see how close the wheel was to the inner rear wheel tubs and those bolts. I went back and forth on tire size for a week or so before I said YOLO and ordered 315/35/20s in the back and 255/40/20s up front. Yeah yeah, they don't match. They couldn't get the matching set, but they're both Toyos. One Proxes 4s and the other Proxes Sport or something

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Backed it out and man I couldn't take my eyes off of it

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Unfortunately, one of their guys didn't know what he was doing and had ruined the rear wheel with the tire machine. So they had to order me a new pair. I still have these stashed for someday when I build a matching truck bed trailer
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So at this point, I just drove the truck for a while and enjoyed it. Wasn't long after this that I sold my daily NBS and this was all I had. This would've been around the time that gas was down around $1.20 or so, so running around in a premium swilling hotrod didn't hurt too bad. I daily'd it, took it to several different shows and just enjoyed the hell out of it for several months this way.

The first C10s in the City in Atlanta
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Hanging out at Howe's It Doin Garage with my buddy Rick (SQRBDY, he sells cool merch) and his LS swapped '86
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On our way to SETN '21
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Re: Huck's 85 GMC shorty
 

huck, enjoyed the build & looking at a nice truck!! I too have had a few "dealings" with the AC D pumps (EP 381) I installed 2 in my '86 LS SWAPPED truck (build on here) and one failed after about 3 startups. I grudgingly replaced the bad one with same like and kind, so far I THINK both are operating correctly. my issue is that I get "lean pops" at initial start up - for about 1-2 minutes, then it seems to run fine (no codes) my tuner thinks my FP needs to be more (currently steady around 52-55PSI). he thinks I need to replace the delcos with Whalbros and separate filter and regulator.... aarrggg. anyways very nice truck & maybe catch you out here "in the desert" soon... C10 reunion maybe! :metal:

Re: Huck's 85 GMC shorty
 

Thanks! I'll keep updating this thread to get up to current times. I've been out your way for Dino's Git Down the last 2 years in Glendale. I work for AMD and we had a booth set up there, gave away a whole squarebody body in '22 and several bed kits this past year. Hoping I get to go again this year.

Your fuel pressure is definitely just a touch low, you should be at 58psi. For my setup, I'm running the Walboro in tank 255 in a stock '87 TBI sending unit. I ran hose along the driver's frame and mounted an '06 Corvette fuel filter/regulator where it's easily accessed. Then a return line goes from that back to the tank and a supply goes to the motor. That filter/regulator combo is set at 58psi for the stock Corvette. I stick with either AC Delco or Wix though, I've had issues with off brand filters and so has my tuner. Something to think about.

Re: Huck's 85 GMC shorty
 

So like I said, I drove this thing everywhere, even drove it all through winter '21/22 cuz that was my only vehicle. It was around this time that we started using my truck pretty regularly for test fitting of new parts at work. The first one being bumper brackets for the sport bumper. So off comes the nasty ole dealer bumper

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