1983 Big Block Monte Slow Build (Lowered Expectations)

Supercharged111

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Oct 25, 2019
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It was just out of gas thank God. That means the chainsaw premix I dumped in it to get it to the gas station when I first started it has also run its course. Now there's 6 gallons with Stabil in the tank. Once I got some temperature in the thing it wouldn't rev past an idle without pooping out the carb and intake, so I went to O'reilly and got a chunk of brake line and made an APT tool.

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Fits like it was made for it and the sticker helps me count turns. The 2 1/4 turns I started at is clearly not where it was before. That's what I get for milking a carb rebuild for 11 months. My only saving grace so far has been my ability to find what I had before in my old posts. So the car was previously idling at 13-14" and now it's been 16-17" today. I pulled the timing back to the 15 degree mark at idle but the car got hot before I remembered to check total timing once it revved out cleanly. Idle screws still pretty damned unresponsive, I can turn them all in and the damn thing still runs. I'd have to believe 16" of vacuum is enough to suck the needles down into the jets to lean it out enough so that the wife won't b*tch when I walk in the house reeking like exhaust. I think I need to get a wideband involved now to make efficient, useful progress. For now it runs well enough to putt putt around and drive itself on the trailer which is what really lit the fire to get this done. If anyone has a starting schematic for this car it would be much appreciated. It's pretty ghetto that I'm still striking a yellow wire against the positive battery post to fire this thing up every time. I think if I road tripped it as is to Freiburger and Finnegan they'd be proud. One more thing, shouldn't this linkage be bent up to get caught in the choke linkage to prevent the secondaries from opening when the choke is on? I ask because I suspect that is what I need to wire together to tune the primaries at WOT.

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Supercharged111

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Oct 25, 2019
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I took one more whack at it once the car cooled from 220 to 180 (no fan). I tried revving it at 4 turns again on the apt and it seemed OK so I left it there. Next I tried to eyeball total timing but really didn't couldn't tell where it was. I'll have to mark it at 35 degrees on the balancer to see how much advance there is as I didn't dig that deep into the distributor. Cap and rotor looked OK despite there being a distinct misfire at idle.

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There are shenanigans with the plug wires that I've been ignoring.

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But I hate parts store plug wires so will need to go with something custom cut to length more than likely. I then pulled a plug to help me verify if this was a MarkIV or GenV engine. The carb makes it a bit confusing.

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CR43TS coincides with MarkV which is I thought it was. #1 looks like it was fat and is now in the lean side. After this I put the idle screws at 4 turns out. When turned all the way in the engine would only drop 1" of vacuum but developed a very slight stumble. At this point I got brave and decided to go for a little cruise. When cracking the throttle off idle, the engine is very responsive and always has been. After that though, there was a bog. The one time I floored it the thing took off in a way I don't remember it doing but it wasn't a full pull. It seemed pretty happy with the new timing setting. My impression is that I'm either underjetted on the primary mains or that APT needs opened up some more. Really though a bog doesn't happen when you're a little bit lean, it happens when you're a lot lean. Furthermore I feel that overdoing it on the APT is going to screw up other drivability aspects, so for now without even looking at a wideband I'm going to order up 72-74 mains and see what they do. In the meantime I'll reinstall the exhaust that fell off and cut my drive short and try faking it with the APT.

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That's right, no 1 wheel peel today. I made it about 1/4 mile before it fell off and I ran it over to add insult to injury. Doesn't look any worse for the wear. I'll see about clipping that turndown too.
 
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64nailhead

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I wouldn't get too wound up over reading a plug yet. Need to get it to where you can make a WOT pull or two to see how it's working.
 

Supercharged111

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Oct 25, 2019
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I wouldn't get too wound up over reading a plug yet. Need to get it to where you can make a WOT pull or two to see how it's working.

The plug reading was more of a sanity check. I was convinced the fuel stink was due to it being pig rich, but we can clearly see it is not excessively rich at idle. Furthermore once I made that brief drive the car simply smelled like normal catless exhaust so I'm done lingering on the notion that it's pig rich. I also think part of the reason for the stink is the fact I run it in the hangar. I bet if I pulled it outside every time it wouldn't be so bad. That and the fact that the choke will make it feel until the engine warms up. So yes, I do want to make a WOT run with the secondaries wired shut to get a better idea of what's going on.
 
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Supercharged111

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I learned another fun fact today. This wheel is only clamped on by the force of the lugnut in the middle. When it was dead and I dragged it out of the hangar to put gas in the tank I tried to turn the wheel and it just spun. At first I thought something was broken, then I took a closer look and realized the steering wheel was moving without the rest of the stuff.

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64nailhead

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Makes for more interesting test drives lol.
 
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Supercharged111

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Oct 25, 2019
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I went thumbing through a notebook my dad had and found the page with casting numbers. Assuming they're correct, the engine in the car is as follows:

Block: 12550313 GenVI
Heads: 12562932 GenV
Intake: 14087487 MarkIV

This was a crate engine from GM. The thing that confused me is that, on the GenV, you can't run MarkIV or GenVI heads. Apparently you can run GenV heads on a GenVI block? Either way this is excellent news. I can slap some less bad GenVI heads on that will flow a little better and add some much needed compression to go with the bigger cam it so desperately needs, go with some old school large port ovals, or aftermarket heads if I find a smoking deal on them. I know the crossover head gasket was an option for the GenV, but the GenVI is a much better starting point. Only thing I can't find is compression specs for this motor. I.E. will it be 9:1 with 100cc chambers or not? I think the GenV was something disgusting like 7.9:1.
 
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Supercharged111

Comic Book Super Hero
Oct 25, 2019
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Colorado Springs, CO
Decided to swing out and slap some valve cover gaskets in. All the allen bolts were tight and the hex bolts were finger loose. Here you can see why I went after them.

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You can see it sucked in some needles, time to change the oil now that it's sealed up again. The other side had a cut gasket as well. Plus that orange silicone just had to go.

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Looks like the stud threads were lined with it as well.

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They cleaned up great with minimal effort.

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Looks like I get to do a dipstick with the oil change.

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Once I'm off the crutches I want to throw it on the lift for the oil change/dipstick so I can rehang/weld/trim the exhaust. I also want to grab a recurve kit for the distributor. I saw a Mr. Gasket one at O'reilly's but it said it was for 74-79, I thought HEI was all the same but I guess not.
 
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