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Nice! I'm learning a lot! This will be most helpfull, as I'm planning to put an LT1 in my wagon.
 
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Discussion Starter · #142 ·
Wow, a month since my last post. I love my life, I tell you what. Every day is a new adventure. Not always with B-bodies, though. Anyways, let's keep moving.

If you hang around me enough, you'll learn I have no love for stock injectors. They're an early 1980's design that never imagined the government would connect the food supply with the energy supply and make ethanol in a fantastically inefficient way. But.. efficiency is not a government's strong suit. So, along comes ethanol and there goes our injectors. I've been fighting these things since I first got into B-bodies. So of course I'm going to replace these.

They had sat for at least 7 years so that's even worse. The car would intermittently misfire at hot idle. Turn on the headlights or AC and the misfire goes away. The only thing I could think was that the injectors weren't able to work reliably at really low pulsewidths, and adding the electrical or AC loads lengthened the pulsewidths enough to avoid the problem.

So I pulled the fuel rail and original injectors out. In the center is the O-ring kit that user babywag used to sell. These replace all o-rings that AREN'T on the injectors.
198469


Time to disassemble the rails and replace the front and rear o-rings.
198470


Screen was completely clean on the regulator. It tested at 46.5psi at idle with the vacuum line disconnected and plugged, which matches what I've seen with every stock LT1 regulator; it drifts high over time. The vacuum port was dry, meaning the diaphram was not torn and leaking gas into the vacuum line. This will drive your PCM crazy trying to adjust for it.
198471


Here's everything clean up, reassembled, with the newer injectors in place. You do not need the retainer clips that came with the stock injectors; they were for manufacturing purposes only (same with those stupid #3 phillips screws on import brake rotors). If you'd like a set, I have a few left. You can read more about them here. They are 36lb/hr at LT1 pressures, so the PCM will need to be reprogrammed. I can help you with the '94-95 cars; for '96-97 LT1s you'll need someone with JET DST 14005 to reprogram the PCM.
198472


I had a car fire once and it sucked. Ruined a decent B-body too. I don't mess around with fuel systems after that. You end up being paranoid that the car is going to catch on fire at any moment. Now I know this car's got all new o-rings up front. Drive happy.
 

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Discussion Starter · #143 ·
It's amazing how many parts are on a car. There's a reason Tesla has really struggled to get their First Pass Yield (FPY) anywhere near the 86% plus that veteran automakers regularly achieve. BTW that means that for every 100 cars off an assembly line, 86 of them are perfect the first time. Given the number of components, fasteners, wiring, etc, that's pretty impressive. I like the concept of electric cars, but the idea that some startup can just come in and demolish established industry players in a highly complex business is naive. Anyway...

I replaced the partially retracting radio antenna with a good one I got from the junkyard years ago. The top part I'm holding can be unscrewed with the correct tool, or a careful use of two #1 flat blade screwdrivers. Mask the paint if you're the least bit sloppy. Impala parts are black, all other B-body collars are chrome. Another screw inside the front door jamb, then you have to loosen the inner fender to get it out through the wheel well. My inner fenders were already out so easy peasy.
198473


What's the proper name for this bracket? I suggest: "the nose."
198474

Keep your comments about my outfit to yourself. I have my reasons.

Backside of the hood latch bracket.
198475


ABS bracket.

198476


I don't have a sandblaster so I just wirebrushed and degreased all these parts. I hung them on the kids' zipline in the backyard for painting. What a sight.
 

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Discussion Starter · #144 ·
The last thing I need is a failed cooling fan on the road. Since the radiator's out, let's put some new motors in. Not to start a debate, but though you can lower the fan turn-on temps from 225/232 factory settings, it comes at the expense of fan motor life. The only time you really need fans at all is when you're moving slower than 25mph. Further, having hot cylinder walls helps close up ring gap and a hot intake manifold helps more fully vaporize fuel, so idling very hot is more efficient.

Old motor.
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New motor for comparison.
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New motor installed. Note that the shaft with the fan nut is reverse threaded.
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The factory wiring harness is in excellent shape so I reused it.
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I did the same for the other side; I'll find pics here soon. I'll say it's amazing how quiet the new fan motors are. You really don't even know the fans are running unless you know they're supposed to be on!
 

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Discussion Starter · #145 ·
Here it is. Pretty simple to replace fan motors. Just be sure to match watts for watts. There are three different size motors that I know of. The biggest is 240W, which is around 20 amps continuous in a car. The factory wiring is marginal at best. I know Gary at Innovative Wiring makes very quality replacement harnesses for headlights, fans, and electric water pumps for these cars. Not cheap, but constructing wiring harnesses properly is time consuming.
198481
 
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Discussion Starter · #146 ·
Maybe this is a redundant post; if so, I'll delete it later. The new steam pipe came with the little seals on the lower left. Apparently they are prone to leaking; the tribal knowledge solution is to replace them with Dorman oil drain plug seals, part number 097-025. You'll need four. You could also build your own steam pipe, but be aware that the thread on the heads is NOT tapered like pipe thread, since it's banjo bolts flowing the fluid. Given that Keen Parts sells these for around $90 plus shipping in the US, and they took a lot of coaxing to fit, I may just build my own next time.
198482
 

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Discussion Starter · #147 ·
New water pump getting installed after I test-fired the motor in the car to ensure that the ignition, fuel and oiling systems were working properly. Be sure to grease the splines and then install new o-rings inside the coupler, as a guard against corrosion. On LT1s, you'll be doing water pumps now and then. Directly at the top center of this picture is the weep hole, drilled directly up to the bearing behind the water pump seal. When fluid comes out of this hole, it's time to replace the water pump. Though some might think that coolant kills optisparks and it's worth tapping and routing this hole away from the distributor (and I've done that in the past), I doubt it. I think the real optispark weak point is busted vent harnesses, and the seal around the 4-pin harness failing and allowing oil in. I see oil inside optisparks far more than coolant.
198483


One other note; I strongly suspect that people with repeated LT1 water pump failures have a misalignment that puts extra stress on the bearing. There are locator dowels on the LT1 block that the water pump should fit snugly onto. Buying a new casting is your best bet, assuming the casting is machined properly so that the dowel holes are properly located relative to the water pump drive shaft. If your rebuilt core is loose, try lifting it up while snugging the bolts so that the water pump is centered on the shaft, not hanging down by gravity. I did that here; we'll see how it does.

Finally, put a thin layer of grease between the water pump gaskets and the block. It'll make removing the gaskets much easier later on, and they won't leak.
 

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Discussion Starter · #148 ·
This picture shows the rear of the AC compressor. There's a lot going on here.
198485


  1. The rear bracket holds the compressor against the block using one of the original small block chevy motor mount holes. There are two 8mm bolts holding the bracket to the compressor. The bracket holes have slop in them.
  2. Notice the two washers between the bracket and the block. Originally the AIR pump crossover pipe mounted here. That pipe's bracket was about one washer thick. I'm not sure where the second washer's room came from, but they both fit so in they go.
  3. Not visible in this pic is the slot I made in the bracket out of the block mounting hole. Otherwise you'd have to lift the compressor over the rear bolt to install it. GM didn't care because when they built the cars, they just bolted the AC compressor to the engine and then put the engine in the car. With a slot, you can slide the compressor back in, align the washers, and install it all the way.
  4. The compressor is held onto the front accessory bracket by three bolts. Tighten those first.
  5. If I didn't put these washers back here, when I tightened the bolt at the rear, it would have distorted the case and caused a leak for sure, if not compressor failure due to internal misalignment.
  6. I removed the stud in the block and just replaced it with a bolt. It's hiding behind the bracket but it makes getting a socket up there easier than the stud and nut combo the factory used.
  7. Once the big bolts were tightened, I tightened the two 8mm bolts. I tried shifting the bracket around but still needed the two washers. I shifted the bracket over so the bolts are tight against the side in the same direction that the serpentine belt is puling on the nose of the compressor. Note that I could only tighten these bolts afterwards because there were no inner fenders, coolant lines or AC lines in the way. I was at max OCD here. There's no way you could do this with an AC compressor replacement unless you drained the cooling system and removed the heater lines and the AC compressor lines. Worth it for a nut like me but probably not for most people.
  8. I tried several ways of routing plug wires around this bracket. I wanted them all to go on one side, but this way just "worked" best overall. Make very sure that the wires and looms are not squished anywhere. The gray lines on the looms indicate that it's high-temperature loom.
  9. There's far less room to work than this picture shows. The 94-96 frame crossmember was modified from '91-93 just to make room for the back of the compressor. This whole job took way too long, but better to do it right up front than have to replace a compressor in a year.
 
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Discussion Starter · #149 · (Edited)
In case you were wondering how to get to the upper bellhousing bolts on the transmission... this is how. Of note in this pic:
  • The brass hex plug is the line pressure test port. This is where you'd put a line pressure gauge. You COULD mount a temp sensor there but it will heat up quite a bit by the catalytic converter when stopped.
  • The shift arm is for the floor shifter. It looks very much like the one GM used on floor-shifted Chevy Blazers of the late 1990s / early 2000s.
  • I had misplaced the bellhousing bolts so I temporarily replaced them with hardware store bolts. Turns out they were slightly too long; that one there broke off shortly after this pic was taken when I was adding the wiring harness bracket to it. I called my mobile welder and he crawled under the the car and got it out. Then I replaced all the bolts with the correct ones. Those were six expensive bolts, for sure. I have proper ones in there now.
  • Never run without a torque converter cover on. Rodents and other things can get up in there and make a mess.
198486


See the blue area in this pic? See the gap? This is good. If you have the torque converter fully seated, you will need to pull the converter outwards toward the engine slightly to bolt it to the flexplate. Again this is the way it should be.
If you put the transmission in and the converter is tight against the flexplate, it's not fully seated in the pump and you WILL crack the pump rotor shortly after you start it. Pull it back, spin the converter and push it into the trans until it clicks one more time, then install.

No gap, no install. Novice gearheads make this mistake all the time on automatic transmissions of all makes. Even I did it once early on.
198489
 

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Love catching up with this thread!
 
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What a gorgeous flywheel.
 
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Though some might think that coolant kills optisparks and it's worth tapping and routing this hole away from the distributor (and I've done that in the past), I doubt it. I think the real optispark weak point is busted vent harnesses, and the seal around the 4-pin harness failing and allowing oil in. I see oil inside optisparks far more than coolant.
THIS^^^^^^

I'm on waterpump #4? All 3 previous pumps peed hot coolant all over my opti for hundreds of miles over the years. Once I even ran the latter half of a road course day with the water pump dripping on the belt enough to make the serpentine belt slip enough to temporarily cut my power steering in slow corners here and there (don't tell the track staff - but it was a wet track anyway :censored:) STILL on my OE opti that I did an MSD cap/rotor on at 100k, now at 203k miles. Check and replace your vent harness!
 

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Discussion Starter · #154 ·
So.. about those slightly-too-long bolts...
198535


Fortunately I got all the other ones out, but I had to call my miracle worker to get this one out. The trans had to come out again. Talk about killing your momentum.
 

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Discussion Starter · #155 ·
Heat and moisture are friends with corrosion, so before I put the exhaust back in, now's the time to drop the heat shields and clean/rustproof/paint the underside of the body. Southerners may find these photos disturbing, but it was actually pretty clean, and no rust-through at all.
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198537


198538


It's interesting how easily good ol' Brake Cleaner takes the Dark Cherry overspray right off.

This pictures is under the passenger side looking straight up; the bottom of that body mount box is completely solid. Even though the rest looks a little scabby in places, this body is in good condition.
198539


Driver's side scraped and just about done prepping.
198540


Factory heat shields, with some sort of tar-based undercoating on the passenger side one. That goo took a LOT of work to remove!
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Upper sides; I wire wheeled these after cleaning, then degreased one more time, then sprayed on some beautiful silver for max heat reflection. I also masked and sprayed the bottom of the body silver as well. I can't find those pics in my phone album; Oh well, I'll go under and take some more here soon. Who wants hot feet on a hot day? Not I, and not anybody in my car, that's for sure.
198542


I'm actually thinking of spraying the bottom of my gas tank silver to reject asphalt heat; if you watch your fuel economy, it goes down as the gasoline in the tank heats up. I remember our family road trip through the American Southwest in June how blisteringly hot the pavement was. The fuel pump in my minivan whined so loudly out there, and in the 60,000 miles since, it's never been as loud as it was in New Mexico and Arizona.
 

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Discussion Starter · #156 ·
And.. voila, the trans is back under the car. One downside of the QuickJacks is that you really can only get the trans in and out through the front or rear of the car. And you have to get the trans on and off the transmission jack before you can get it out. There's no room for leverage. My son had to help me slowly lift the trans up onto a stack of 2x6s, then slide it over onto the trans jack.
198544
 
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Discussion Starter · #157 ·
Ah, just found all the pics. The silver doesn't hide any flaws, that's for sure. But down here, I need function over form.
198545


198546


Driver's side heat shield installed:
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Passenger side heat shield installed:
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Overall. Nice and shiny to reject that catalytic converter heat. I painted the stock crossmember too; that took a LOT of time.
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Last shot of the passenger side before I put the catalytic converter on. Even though that starter looks terrible, it works perfectly. It's on my list to disassemble, clean, replace the brushes and solenoid and it should be good as new.
198550


Driver's side. If you look just to the right of the exhaust manifold outlet, you can see 327 on the side of the block. That's how you can tell if it's an LT1. The smaller L99 4.3L V8 had a different number on the block.

198551
 
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Discussion Starter · #158 ·
Last shot of driver's side before the transmission and catalytic converter went back in. That wiring harness off to the left goes to the upper left transmission bellhousing bolt. It was just pulled out of the way for now. That big dowel sticking out of the back of the block is one of two that locate the engine and transmission, and resist most if not all of the engine's torque. Just to the left of the dowel is the VIN stamp area on the engine. You can barely make out the edges of the numbers if you squint. Or not.
198552
 

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So.. about those slightly-too-long bolts...
View attachment 198535

Fortunately I got all the other ones out, but I had to call my miracle worker to get this one out. The trans had to come out again. Talk about killing your momentum.
OOOOOOOF!!!! That sucks! Glad you got it out!
 

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I'm actually thinking of spraying the bottom of my gas tank silver to reject asphalt heat; if you watch your fuel economy, it goes down as the gasoline in the tank heats up. I remember our family road trip through the American Southwest in June how blisteringly hot the pavement was. The fuel pump in my minivan whined so loudly out there, and in the 60,000 miles since, it's never been as loud as it was in New Mexico and Arizona.
i'm very curious to see how this works! I actually live in Phoenix AZ, and to be honest I've never noticed an MPG drop in the summer. But I'm sure I've just never noticed it, and since summer is approaching soon :( ill try and keep track of it this time.

The pavement gets so hot here in the summer that the tar in the road melts and sticks to your shoes!
 
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