My 1980 Sierra LWB build

[C15_Sierra]

with PICS: after this weekend, I feel like a kid a few days before Christmas! Even with the Thanksgiving family obligations, I think I'm about a week away from getting the engine running (with open headers )

Tally of this week's work:
-Finished putting the intermediate shaft in, and buttoned up rest of the steering column

-Buttoned up the cooling system...I used OEM '00 Silverado hoses, only had to cut 1-5/8" off the bottom hose...top hose fit fine, and I used 3ft of hose each for the heater inlet/outlet

-Installed the turned-down SBC temp sender (for the gauges) in the pass. head (thanks CamaroChris!) - I'll know once I fire the motor how it corresponds to the readings of the PCM

-Installed the Burb cluster, wired in all the connections

-Mocked up the rest of the intake and installed a new battery tray - I'm gonna have to make a custom heat shield or something, or I'm gonna have massive heat soak

-Installed OBD-II connector (still need to wire up)

-Wired in MAF connector (got cut off by the junkyard)

-Installed new filter/gasket, and cleaned up the 4L60E

-Other odds/ends I'm sure, not coming to mind right now...

Anyway, PICS!

Starting to look like an engine:


Future heat-soak-r-us


Everything fits!


Can't wait to drive w/ this thing:


Burb cluster, tach will go on the column


Not stock for 1980


4L60E, ready to go in tomorrow

[C15_Sierra]

Holidays ate (no pun intended lol) into my work time this week. Got the tranny in on Monday, along with the TransDapt crossmember - I used the 3" drop version. Everything went in smoothly, except I needed to relocate the fuel filter forward a couple inches to clear the crossmember.

Interior-wise, I buttoned up some more cab wiring (tach, OBD-II port, column wiring) and installed the shifter cable.

Next came exhaust work. I fitted the '88-'98 Schoenfeld LS Swap headers to check final fitment. Both sides clear the frame plenty, the only points of concern are the drivers side lower control arm clearance (clears, but barely) and the passenger side collector exits close to (didn't get measurements), and in-line with, the trans crossmember. Will have to talk to the exhaust shop to see if the flanges I bought will fit.

Header pics...

[C15_Sierra]

Had much better luck using Jegs Push-loc fuel injection hose. Was using Russell-brand push-lock, and the fittings wouldn't go all the way on, even with lube (joke all you want), vice, muscle, you name it.

I dropped the tank again to re-do the return line with Jegs line. I decided to relocate the fuel filter, along with the feed (obviously) and return lines to the drivers side frame rail because there's a lot more space up to the engine. After mounting the headers, it was near impossible to run the lines without interfering with the exhaust. Also, the bends were less tight in the fuel line.

The only hard items remaining until she starts are:
-Tranny cooler lines (I have rubber line, just need to get the right -AN fittings)
-Driveshaft (out for shortening)
-Neutral safety switch/range switch and shifter arm (guy at work who worked on my tranny forgot to put it back on)
-Steam vent tee
-Fuel pump, starter, charging circuit wiring

And then, of course, fluids!

[Skellington]

looks like a nice build. Keep up the good work... and pics.

[C15_Sierra]

Got the driveshaft in (measurements were right on! ) and tranny cooler lines in, and plumbed up the steam vent line (top of the radiator)

Next, I'm gonna take the headers back out, strip the paint, re-paint in VHT, and wrap them to keep underhood temps down and to help shield the headers from the tranny cooler, fuel lines, and shifter cable.

Fuel pump, starter, and charging circuit wiring will go in tomorrow too. I MIGHT have a running engine by weekend's end!

[C15_Sierra]

I'm gonna stop posting that I'm *this* close to running, because every time I do, something else comes up...

Turns out that finding a connector for the O2 sensor is harder than I thought, and its really pi**ing in my punch bowl right now...first, I got sent the wrong (square-4, need flat-4) O2 connector. No biggie, 'preciate the thought. Next, I visit the local yard, they can't help me. Grr....Then I ordered the right connector from Mouser along with what I *thought* were the right terminals. Turns out I was wrong (and not even close to right), and I have the wrong terminals but the right connector. But hey, I pulled out all the unnecessary connectors and pins from my harness, so I must have some pigtails with the right terminals. Nope, none of those connectors fit, despite looking like they should go into that connector. Now, I'll be delayed ANOTHER week while I order the right friggin' parts just so I can splice into my harness to repair the ONLY O2 connector that was cut off by the freakin' yard. They saved the ones I didn't need, but had to cut off one of the ones I needed. Kinda the story with this engine that I bought from the yard...lots of little stuff broken/missing that I missed upon closer inspection (hey its my first build, doing it mostly by myself)

Which brings me to my next point, the dipstick....Second to that O2 connector, dipsticks are in short supply. Struck out at 2 yards already, and I'm about to go on the prowl in my neighborhood for any truck that has a 5.3 to take theirs. What happened to mine was that it was already fragile from being bent when I got the engine, and when I went to straighten it (it was bent at the o-ring, preventing it from fully going in) it of course broke.

I also don't know if my vacuum line for my brake boost is gonna leak, the connector/o-ring doesnt feel like its seated all the way, but won't push in any further. Also, its strange to say, I can't tell if its broken. Something tells me there's more to the intake end to pilot the hose, etc., but I can't tell if it's broken

[C15_Sierra]

Despite the above post, I've been making baby step-like progress towards starting. Finally figured out all the cab wiring (as simple as that task is, I'm electrically "special") and where I'm gonna make my connections.

Temps in the garage plummeted with the outside weather, which kinda precluded me from doing any painting of any sort...small enclosed spaces, solvents/paints, and propane heaters don't mix. So I didn't strip/paint the headers as planned, I simply just wrapped them (THAT was fun). When time/funds allow, I'll do it up properly.

Finished the shifter install (minus trim, that will go with the interior work planned for later this winter/next spring). Got it adjusted so hopefully I won't run into any issues.

Got my fuel system all buttoned up from gas tank to rail, so nothing more to worry about in that respect.

Back to cab wiring, I tested circuits with a small hobby battery from the 'Shack. Kinda surprised me as I didn't think the cluster would light up and cause the seatbelt buzzer to go off (yea it still works...). But anyway, I was worried since I swapped out the column that not everything would work. But the important functions do: stop, start and run. The turn signal flasher wasn't working (batt might be too small to run the flasher? though I've never seen that before). Then the turn signals stopped working and would only turn the parking light (of the appropriate side) on. Then it started activating the seat belt buzzer when the headlight switch was pulled on. So the question is, do I have a short, or is it because of the tiny battery? The truth will be found out soon enough.

I got my aux. battery tray in so I can run the battery in the stock Silverado location, and turn the pass. side battery into a makeshift airbox for the intake.

I don't have a consistent schedule on this thing, so who knows when it'll fire...

[C15_Sierra]

Note to self...venting on the internet provokes rational thought...

[C15_Sierra]

Weekly update:

Temps got pretty cold this weekend, and even with my propane heater, the garage floor is still stone cold...so I worked until my feet froze off both days...

I eliminated the stock Silverado junction box because I couldn't find a clean way to mount it. I built the fuse/relay block from LT1Swap, and mounted it on the drivers side inner fender. I installed the driver side aux. battery tray and mounted the ECM under that. With the battery sitting on top, you hardly notice its there. Sorry, no pics yet (oops).

Once I got the wiring buttoned up and connected to the cab, I charged the battery and went to switch on the cab power. Nothing. I've got headlights/taillights/parking lights/dash lights, but no brake lights, hazards, turn signals, or switched 12v power. I've got good voltage going to all the junctions/connections so I'm chasing bad grounds now. I've detailed some of my specific symptoms in my other thread (http://67-72chevytrucks.com/vboard/s...d.php?t=499053)

Was hoping to having it started by the weekend, but nope. But the good news is that I'm closer to being done than when I started the weekend, so I gotta keep my head up!

[C15_Sierra]

After my experience with my wiring connections between the harness and cab, I got it to where I got power to the cab.

Changed the oil filter out, filled up w/ oil. Didn't get to filling the tranny with ATF until after stores were closed, and found out I don't have a funnel small enough to fill the tranny without making a mess.

Now I have another issue, now with my engine harness. Luckily its not preventing me from getting it running, as I jumped the wire coming from the cab into the starter solenoid wire - so, starter works now. I will investigate later.

Installed O2 sensors, tightened up all connections, installed plug wires. All I need to do is fill the tranny with ATF, fill with fuel, and flick the starter switch. So, fingers crossed, tomorrow will be the official "attempt to start" date

[Gordonr1973]

Good luck with starting it!!!!

I hope it lights up on the first try! ---Remember to post a video of it running if you can please

[C15_Sierra]

Well, there's no other way to say this...

SHE'S ALIVE!!!

It started up first try, the vid is actually the first crank. I didn't run it too long because I haven't added coolant yet. I'm waiting on a new evaporator box to be delivered any day now, so it didn't make sense to fill the radiator up just to drain it in a couple days. But she starts, coughs a bit, and settles down as the computer figures out where the idle is. Doesn't help that I'm running open headers and the O2 sensors are roughly 3" from the end of the collector, so I bet some fresh air was throwing the computer off. But she does idle on her own, and it sounds so nice!


I am still excited that it fired up right away. It's my first project by myself (aside from my engineering projects in school and such) as well as a rolling learning experience, and it's been a long time coming to get the motor fired up because of my work and other time commitments that keep me away from garage.

Here's the vid...I got so wrapped up in the moment that I forgot I was holding the camera LOL...dunno why I shut it off with it still running, so the vid is a little short. I'll probably be getting an exhaust for it sometime soon, and when that happens I'll post up another vid (so that I don't toast the O2 sensors, my ears, and my neighbors nerves!)

[C15_Sierra]

Well I forgot to plug the vacuum booster so that's why the idle was rough. Went to plug it and realized it fell out...diagnosis: the fitting is broken off inside the intake. Another win for the junkyard. So, next will be taking off the intake manifold to get that piece out

[mooseknuckles]

the headders look like they fit ok, but I see how much the oil pan hangs down, not a problem for you so much but my truck sits a lot lower than yours, and I may have to switch pans......good build btw. keep it up.

[C15_Sierra]

Haha yea you're a little low As I recall though, a friend of mine who swapped an LS1 in his '84 GMC swapped his pan (engine was from a Trans Am IIRC) with a 5.3 truck pan, and his is lowered a bit (and is a DD). There are some pans that will fit, some will not. I have my motor mounts set back 1" and that made my pan JUST clear in front. I guess it depends on your overall setup, but there should be some other car pans that fit

[Low84]

Maybe I overlooked it but what motor mounts did you use? And what did you have to do to get the 4l60e to fit? I'm about to dive head first into my lsx swap.

[C15_Sierra]

I used Swaptech adjustable motor mounts in the 1" back position (moves the engine towards the rear) which bolt up to the stock SBC clamshells. I went ahead and replaced the motor mounts (mine were a bit worn out) with the new stock SBC motor mounts. The P/N on the SwapTech mounts is STM-EN-03-501, and I got 'em on eBay (you can find them elsewhere too).

To get the 4L60E to fit, I used the Trans-Dapt 3" drop crossmember (TRD-4539)...I already had a urethane trans mount from the kit that I bought for the suspension/body bushings.

Since I had a TH350 previously, the driveshaft yoke was the same as the 4L60E, all I had to do was cut the stock driveshaft and it fit perfect. I re-used the stock 2-piece d/shaft and had a shop remove 4.5" from the section forward of the carrier bearing.

And that's pretty much it...I didn't have to grind away any of the frame to get my exhaust or cooler lines to fit, all I had to do was drill new holes for the Trans-Dapt crossmember. Good luck with your build!

[Low84]

Thank you very much, part numbers and everything!

You made this look easy, lets see how bad I screw this one up.

[C15_Sierra]

First update in a while...doing this from work so I can't upload pics (I didn't take many in the first place)

January was a slow month for working on the truck. My motivation sank, the garage was too cold, etc. I found enough excuses. But, here's what I did:

-Removed the intake from the engine and cleaned off the head surfaces. I soaked the intake in Simple Green for a couple days and scrubbed the interior down to remove the old oil and carbon mess that accompanies EGR and PCV usage. I then used the parts washer at work to get the remaining stuff out. Let it dry for a while, blew the rest out with compressed air and let it sit some more before installing it

-Removed the fuel rail and inspected/cleaned the injectors while I had the intake off

-Temporarily fixed my brake boost line (I'm still not 100% satisfied). The line seems to be in the fitting tight, but the fitting itself may need to be sealed with silicone/epoxy. I'll drive it around and see if it's a problem

-Replaced the master cylinder on the brake booster I bought. I installed the booster and now I have power brakes. Still need to bleed the system.

-Spray painted my rallys the correct color (Argent Silver from Eastwoods) - they look much better now!

-Started repairing my AC evaporator box. I found out that I have a chip missing in the blower housing and a chunk missing from the lower part of the case around the evaporator. I bought some fiberglass patch and I'll repair it before I install it. Need to install it before hooking my heater lines back up and run coolant

-Fired it up again once the intake and fuel rails went back on. It now holds idle on its own and sounds better. It still needs an exhaust

The list of immediate work to be done...hope to have it driveable by next week:
-Bleed brakes
-AC evaporator box install
-Coolant, ATF top off w/ engine running
-Exhaust shop

[Kerlijah]

Great thread, looks like a pretty solid truck. Looking forward to progress pics!

[C15_Sierra]

Got some weatherstripping done this weekend on both doors. Man, does that make a difference. I'm sure the weatherstripping I took off was the original because nothing could be as hard as the stuff I took off unless it was baked in the Texas heat for 32 years!

Here's what I started with (Pass. side):







And here's the finished (Drivers side):





Some progress pics:





I used the weatherstripping from 1A Auto, also learned some beforehand with their instructional video on YouTube. Definitely gave this first-time a sense of confidence in something that is actually pretty easy. Plus, a bonus for Northeast guys, their warehouse is in Mass., so a lot of the stuff (like my gas tank that I ordered from them) arrived next-day with standard shipping. Of course, I've had this weatherstripping since I was in Texas but that's another story

I also just finished putting the evaporator box back on so that I can have some heat and I can finally run coolant through the lines and bleed the system. I also swapped blower motors from my old setup because I know it worked (didn't want to tear into it again JIC the one the box came with didn't work). Here's a shot of it installed:



And a shot of one of the repairs I did. When I went to install it, I found this crack in the blower motor housing and a chunk missing on the bottom (not pictured). I was able to patch them both using fiberglass. I'm not sure if it was me, the shipping co. or the eBay seller I bought it from, but I didn't discover it until a month later, so either way it was my bad. Anyway...



Here's a shot of the new master cylinder:



As a little pick-me-up, I mocked up the new dash pad and my old bezel, just because I was getting sick of looking at the bare dash. Can't say I'm not excited to get 'er on the road!



Next, I'll be bleeding the brake system, wiring up the TCC switch for the PCM (using a stock brake light switch with provisions for cruise control) and then send 'er off to the exhaust shop

[68 TT]

You are making good progress.

To gain a little lower control arm clearance for your headers and improve the handling of the truck too you can do the caster mod to it. This will move the lower control arm 3/4" forward and away from your headers.

I can't remember which build thread I was just looking at but if you search the 67-72 board for caster mod you should find it.

[C15_Sierra]

Thanks for the tip! I'll do a search for the thread, but I'm sure it'll be easier to do when I take off the control arms to replace the bushings with the poly ones I have

[68 TT]

Originally Posted by C15_Sierra

Thanks for the tip! I'll do a search for the thread, but I'm sure it'll be easier to do when I take off the control arms to replace the bushings with the poly ones I have

It is basically drilling a new registration pin hole 3/4" forward of the existing one on the lower A-arm cross shaft and reinstalling the control arm using the new hole. Best time to do it is when putting in the new control arm bushings you have.

[C15_Sierra]

OK, update time. Good news and bad news.

Good news is that the truck starts and runs healthy. It was able to drive up onto my buddies trailer to be towed to the exhaust shop. Good thing I didn't try and drive it there, there was a cop watching us from across the street!

Anyway, we got to the shop and unloaded it (vid below shows my buddy driving it off, I wanted to shoot the video). After he stopped the motor because he couldn't hear me telling him where to put it, I hopped in to turn it around. After I parked it where it was supposed to go, we realized the engine started pi**ing oil from underneath. The only place I noticed it coming from was the oil filter, so I pulled it off to make sure it wasn't double gasketed. Nope. Any holes in the filter? Nope. It's an ACDelco filter, so bad quality isn't likely. I'm kinda at a loss as to how that happened, because the truck had ran a few times before that and had run for a few minutes each time. Only possibility I can think of is my buddy mentioned that a tech friend of his with a 6.0 had to wrench-tighten his filter, which I always thought was a no-no. Mine was hand tight-but I had tightened it pretty well.

Plan is to go back tomorrow morning with a new filter and some more oil, and replace the filter, wrench it on, and see if it holds. If not, I might launch it off a cliff

Anyway, vid for consolation: