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Discussion Starter · #1 ·
[editor's note, I'm migrating this over from GMLongRoof forum, so some of this may be repetitive from my Impala build thread]

Hey guys, it's about time I posted up my wagon project. I've owned B-bodies since 2003, but in late 2013 my fourth Roadmaster wagon sadly caught fire a week after I bought it and was a total loss. I had just moved 1000 miles south and with a new job, three young kids and a whole new city, I needed to simplify. So I sold all three of my B-bodies and just drove minivans for 5 years.

My dad suddenly passed away in fall 2017 and the next summer I ended up inheriting his '96 Impala SS (Dark Cherry, the car I always wanted). It was drivable but needed a lot of work. I was going to sell it, but shortly after I got it to my house the buyer flaked out, so I just drove it and remembered why these cars are so fun (especially compared to minivans!). My wife and I decided to sell one minivan and make the SS my daily driver (which you can do in the Southern US), so I started disassembling it to restore. (That build is over here).

Four months later, while looking for parts, I located a 96 Roadmaster wagon project about 2 hours north of me. The owner had started to build it but hit some snags and health problems and it had been sitting partially disassembled for two years. I figured SURELY he'd be willing to sell some parts from his stash, but no, he said he wanted to sell the whole thing together, and he made me an extremely compelling offer. So I did what any self-respecting guy would do, I told him I'd talk to my wife and call him back.
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We talked it over and decided to go ahead and take a good hard look at the wagon. It was dirty and neglected, but other than a hellacious battery acid leak and an unfortunate rainwater accumulation in the left rear quarter, it was rust free and in very good condition.

So we loaded it up with parts, loaded my minivan full of parts, strapped down the powdercoated rear axle and the 383 he had acquired for it (on a specially designed radial transport fixture) and he trailered it to my house.
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Discussion Starter · #2 ·
The old girl looked good on the highway, heading to a new home and finally, a more certain future.
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The seller was super nice, and hated to sell the car, but he had several other projects he really wanted to get done that were more significant to him. Despite his health challenges, he was a trooper when loading and unloading a dead wagon (no easy task). He even pulled over shortly after we left his house, when he realized there was a box of trim he had forgotten. He called his son and had him bring us the box of parts, then we carried on with our journey. I had literally gotten to his house at 10am and he left my house at 6pm (with a 2 hour drive back). It was a long day for both of us, and a very bittersweet day for him. Hopefully when this wagon is finished I'll be able reconnect with him and we'll go for a drive.
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Discussion Starter · #3 ·
First order of business - that extra motor was a 383 shortblock the previous owner had bought from a local F-body guy. I took it to a local machine shop to get it inspected. Can you believe this is only the second motor I've ever disassembled? (despite 22+ 4L60Es...)

Local race shop, one man show, an engine building genius.
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Pistons were at stock height, 0.026-0.028" down in the bores. 10cc reliefs in the pistons.

Rings in very good shape, a lot of dirt had gotten on the piston walls - K&N air filter (or none) maybe?. Didn't look like a lot of miles on it. A decent amount of piston rock, but I don't remember what he measured. They sure did seem loose in the bores.
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"Well that's interesting" said the machinist as he examined the creative neutral balancing job on the front of the crankshaft. You actually had to rotate the crankshaft to get the front connecting rods out.
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What a balancing job.
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Discussion Starter · #4 ·
Crankshaft appears to be an Eagle cast (budget) crankshaft.
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Pistons are Speed Pro 0.030" over cast pistons.
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Discussion Starter · #5 ·
Oil pump drive gear appears ok for now but starting to wear. This despite the fact that it had a high volume oil pump. (unnecessary unless you have really loose bearings, need for turbocharger lubrication or piston squirters).
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Cam bearings have some wear but not worn out.
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Interestingly, the outer two oil galley plugs did NOT have the 1/32" vents that also oil the cam chain. They appear to have been replaced; they were much shiny than the brownish-tinged ones in the Impala.
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ARP connecting rod bolts on Eagle SR (stock-replacement) rods. My in-the-know contact says those are weaker than stock LT1 rods. Huh. Also note the non-cooler oil filter adapter. We never did check to see if the filter bypass was stuck open. You'll see why I mention this in a later post.
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Discussion Starter · #6 ·
Then we pull the rods off the crank. And find a mess. This was one of the better rod bearings. Not worn out but what a lot of trash in the bearings.
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Looks like someone left pieces of metal wire brush in the oil galleys. Two rod bearings got totally trenched too. This is one of the crank journals.
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The crank would clean up with a polish, and new bearings would fix it, but sheesh! Cleanliness is a virtue, especially with engine building!
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So, short block is usable but nothing amazing. Next post we'll go through the ported LT4 cylinder heads that came with it and see what condition they're in.
 

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Awesome, and tuned in.

Those shots of the internals make me immediately think of blasting media and ceramic and stuff. Not saying that's what happened, but I've just become paranoid.

You just reminded me...

I knew a guy back in the day who had a really nice IROC. He got a DUI, lost his license, and the car sat for a few years. While the car was sitting, mice ate the wiring. He ended up buying another car, and the Camaro just sat for years until somebody showed up on his front door saying that he restores 3rd gen F-bodies, and that he wanted to buy the car. My buddy said no, but took the guy's number.

Eventually he realized that he wasn't going to get around to the project, and time wasn't going to do the car any favors. He called the guy up and the guy came back with a trailer and $1500. The guy wanted to bring the car back over after he restored it, and my buddy declined. It was just too emotional for him, and he didn't want to see it again.

The previous owner of this wagon likely isn't that crazy, but like I said, you reminded me.
 

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Moving on...

The seller had acquired a ported LT4 top end. LT4 specs are well documented online so I'll let you go look there for info. These have not been available new for quite some time so they're a bit rare. The LT4 intake manifold is also unique, specifically matched to the heads.

Chambers have more of a quench pad just above the exhaust valve relative to LT1 heads. That slight step down from the head surface shows that they have not been milled. As there is evidence of coolant in the heads, these have had run time, but whomever cleaned them before porting cleaned them very well. Unfortunately the stock LT4 valves are no longer in place, having been replaced with 2.02 / 1.60 valves. The stock LT4 exhaust valve was hollow and sodium-filled, for light weight and cooling. I hope those ended up in a motor and not as a nasty surprise in the scrapyard when crushed.
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If you notice the scratches on the left side, the seller had stored the heads on the block, and wasn't always the most careful at lining them up with the dowel pins. Probably not going to kill the head gaskets, but still...

I'm no expert on porting but the intake and exhaust ports look very nice. Short side radii were very continuous; no sharp radii or other bumps.
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This closeup makes the throat line look worse than it is. It really was very smooth.
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Discussion Starter · #9 ·
As stated earlier, the cam that came with the motor was way too wild for a heavy street car, so I'll need flow data in order to pick a cam. Off to the local speed shop to have the heads flowed.
BTW here's the LT4 heads part number:
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They had this sitting in the lobby. A NASCAR hemi from back in the day. The exhaust header primaries were huge, perhaps 2.25"? that intake manifold makes the Accel SuperRam look like a child's play toy. This whole powerplant was for sale. I didn't ask about the price.
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I did ask what was new in the performance industry (this is as of December 2018) and they said the Holley Stealth EFI (the one that looks like a 4-barrel carburetor) was selling like hotcakes and every single person who installed one loved it. Why people still use carbureters baffles me.

And the data everyone cares about. I specifically asked for an extra reading at 0.050" lift to help my cam guy. Flow picks up pretty quickly over stock as the valves open. They added some extra lines at the bottom and found that flow stayed at 252CFM all the way to .700 (although I have no intention of opening a valve that much). Exhaust flow at .700" was interesting - when they added a pipe to the port, they picked up 16CFM. Exhaust manifolds/headers matter. How you test matters.
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Unfortunately they were not able to bolt up the intake manifold or the headers I had for it, but at least we have a baseline. They made a photocopy and put it into this huge binder. I asked if I could thumb through the binder; boy they had tested a lot of heads over the years. Interestingly I found where they had flowed a stock LS1 head, and the intake flow alone was as good as the best SBC race head they'd ever tested up to that date. Why does everyone swap LS motors? The intake port.
 

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Discussion Starter · #10 ·
Oh, forgot to post about the ported LT4 intake (P/N 12550631). These are pretty rare, but the powdercoating doesn't hold up that great over time. Porting looked decent.

Bored out for larger throttle body. That huge idle port right behind the opening was significantly smoothed too.
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All the way up and down the runners. I wonder how much this really adds, since outside of some casting flash and maybe a little more radius at the start, the LT1 intake runners are pretty large and smooth to start with, especially compared to the TPI runners it replaced on the L98.
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A number of wagonistas privately reached out to me with major concerns about that crankshaft. Just goes to show you why it's always important to inspect before you buy.

Well, could I put this pile o' parts together and run it? Let's do some math. Between the tiny 54.0cc LT4 combustion chambers (I had them CC'd at a local speed shop), pistons 0.026-28 in the hole, measly 5cc relief in the pistons, using a FelPro 1074 0.039" head gasket I was at 11.75:1 static compression ratio (SCR), and would still have .065+" quench (ideal is 0.040"). If I had the decks milled down to get flush with the pistons, I was at 12.7:1 SCR. So my only options were to buy new pistons or go with larger CC heads like Trick Flows. Well shoot, I have a mediocre shortblock with good heads that is going to cost money to make work.

Why is quench such a big deal? Because it reduces places where carbon can deposit (which create hot spots) and increases mixing, which reduces lean spots inside the cylinder, requiring less overfueling and thus a more efficient, more knock-resistant burn.

So I turned to LT1 Nation on Facebook and other for sale sites and quickly found a number of complete LT1 engines for sale. LS swaps have made built LT1 motors dirt cheap. Eventually I made a deal on an extremely well built LT1, designed, assembled and tuned by a well-known shop, with only 10k miles on it. It looked brand new inside. The seller was a great guy.

I ended up selling the LT4 heads and intake separately on Ebay. The gnarly short block went to a good friend who's fully aware of what he bought. With iron heads and factory head gaskets, it would be a great 10.85:1 street 383 for short money. By the time I was done selling all those parts, the cost of the other motor was the same as what it would have cost me to make the existing parts work. Plus I got vastly better parts.
 

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I was going to tell this story in chronological order but a recent Facebook discussion prompts me to add this now. On the encouragement of an Impala friend, I recently rebuilt the power steering pumps on the Impala and the Roadmaster. Rebuild kits (really they're just seal kits) are dirt cheap on Rock Auto, so I bought two Gates 348393 kits and went to town. It took me about 30 minutes per pump, and another 30 minutes do do the variable effort solenoid.

The real benefit is that you can rebuild it without having to remove the pulley or the mounting bracket. On rusty cars that's a huge deal. There are tons of videos on Youtube of how to rebuild these Saginaw pumps that were used on GM, Ford and Chrysler vehicles for years. The Type1 pumps had the reservoirs around them; the Type 2 pumps have remote reservoirs like our cars. Both mechanisms are identical. At 170k and 145k miles, respectively, both pumps' metal guts were in great shape. So it's just replacing orange o-rings and the nose seal. There's one other o-ring on the regulator valve fitting on Caprice/Impala pumps that needs to be replaced.
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A seal puller made quick work of the nose seal but you could also use a screwdriver if you're careful. A piece of wood and a hammer quickly drove the new seal in. I always put the wood inside a plastic grocery bag to keep dust and splinters off the pump.

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The Buick NV7 variable effort sensor has quite a few parts in it, and you'll need snapring pliers, a 30mm socket with an impact wrench to get it loose. Also, use a punch to mark the orientation of everything before you disassemble so that you can properly clock them as you reassemble. Do be aware that the two thin o-rings on the 90 degree fitting are different sizes so be careful there. The part in the very center just to the right of the long needle has a thin 3/4 hex on it but it does NOT have to be removed and is tricky to get out without rounding; next time I will just leave it.
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I got tired of working on the Impala (well, not working on it, if we're being honest here), and with some nice weather upcoming, several of my car buddies came over and we got the motor and trans out. I pulled them separately; that's just my preference. I couldn't remember where my fuel line disconnect tool was so we just pulled the fuel rail and finished pulling it out. Clean the area around the injectors before you do this if you want to reuse the motor; this one sat outside with no exhaust manifolds for two years and at least one of the cylinders is crunchy so I didn't care. I'll post pics when I get a chance.

First order of business was to disconnect the wiring harness. I later removed this from the car before I washed and painted it. I should have done this on the Impala; it took all of ten minutes.
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This was pretty much how I got the car; no exhaust, nothing on the front of the motor. Mud dauber nests everywhere, and I was sure there was crap in the motor. I'll say this, the TPIS "Happy Hooker" was money well spent. No fiddling around with chains or levelers, just bolt it on to the top of the motor and lift it out. We did have to add some fender washers because we weren't comfortable with the coverage of the existing washers.
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Unfortunately because the motor was disassembled, we had to drain the transmission the messy way, dropping the pan. Boy do I hate this method compared to using the engine to pump it out.
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Rear shot of the driver's side of the block. This was a Florida car; my goodness it's clean. This is the transmission harness running down the driver's side rear. Also note the ground strap.
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Above the passenger's feet is the connectors for the engine bay wiring harness. Takes maybe 5 minutes to disconnect these with a good pick or small flat blade screwdriver. I've already removed the two bolts in the engine bay holding the connector on, and then I can squeeze the retainers in the lower left of the picture and start feeding it out into the engine bay. Do be careful of that vacuum line. It is not terribly flexible.

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Harness ready to be threaded out. There's the AC drain elbow, still intact, dripping on the ABS harness just as GM designed it.
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Feeding the connectors out one at a time.
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Here it is, the whole engine bay wiring harness. Now time to add a Corvette oil temp sensor (above the oil filter boss on the block), performance mode trigger and status lights, lengthen the EVAP solenoid and switch harness per 1slow96, and tuck away the AIR pump wiring back into the harness. More on that later. I just set it all aside for now.
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Time to take the passenger side inner fender out.
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Somewhere in this mess is two bolts. Ugh.
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And of course they stripped, so trusty angle grinder to the rescue.
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Ok, ready to come out.
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So here's our starting point. Very solid, but very dirty. Previous owner had already added a Jeep steering shaft and a newer Saginaw 670 steering box. Plus all new steering linkage. Sharp eyed observers will note new upper control arms and ZQ8 bumpstops off the S10 Extreme. I believe those bumpstops are now discontinued, but other companies make similar bumpstops now. The steering box feels weird. I may end up replacing it with a low mileage used one. We shall see.
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After lots of pressure washing and detergent.
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Kore3 big brake kit.
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Frame was very clean. This is just minor surface rust.
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Let's wire-brush everything for maximum cleanliness. Vintage Craftsman grinder doesn't mess around.
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After masking the side rails, I shot primer and paint. Rustoleum makes primers for both clean and rusty metal; I used each where appropriate. Not visible here is all the work I did with a grinder to get rid of ugly bumps in the welds.
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That parking brake cable is just as chewed up by the frame as the Impala's was. It'll need to get replaced. I ended up going back probably 6 times and adding paint to spots I missed. It's a multi-dimensional frame with lots of nooks and crannies.
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Boy those front body boxes are clean.
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I took my time and masked the calipers and mounting brackets.
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Ready for a new engine. Time to delve into this 10k mile motor and see if everything is ship shape down below.
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Discussion Starter · #18 ·
The original AC condenser had definitely had some abuse. For the price I got one from Rock Auto for, it wasn't worth taking a fin comb and trying to straighten this...
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Especially with this gash at the bottom. Unfortunately this may have occurred while the car slept in my garage for two years. Oh well, let's take care of it now.
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Discussion Starter · #19 ·
BTW this was the stock damper of the wagon's motor. 145k on it. Look at that rubber ring. Recycle bin.
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Discussion Starter · #20 ·
Look at this ugly weld. I yanked that wire off with my hand and cleaned up the rest with a grinder.
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