CK5
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1972 Buick Skylark

Looking to trace back the wire for the distributor to get rid of the resistance wire. Found this in the loom with no insulation covering it.

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I wonder if it's factory and what it's for. All 4 wires are large gauge. Hoping this doesn't snowball into a big wiring project too.

Someone has reloomed the factory harness so now I'm really getting nervous.
 
Back in 1981 I bought one of these for $700. 1970 Buick GS Skylark 455. I owned until about 1989
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Pulling the coil positive wire back to the bulkhead connector. Look what I find just a few inches into the loom.

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Don't think I'm even going to bother unwrapping it to see the level of hack underneath.
 
Anyone know what this spherical do-dad is? I'm assuming it's something for climate controls.

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I also have a mystery hose with a white stripe. There was a hose coming from the cabin connected to that firewall device. This white striped hose is a second hose coming from the cabin. It's between the 2 green lines below.

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Nice! I wouldn't let a 16 year old drive that one! :rotfl: Maybe some day we'll see it in person. There are some things I'd like to see on a restored version.
 
Nice! I wouldn't let a 16 year old drive that one! :rotfl: Maybe some day we'll see it in person. There are some things I'd like to see on a restored version.
Probably be a great stabbin wagon
 
New ignition stuff is all in and running.

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Went with a small cap HEI unit from eBay. All the regular Buick performance parts places were out of stock on distributors. I could have done a conversion on the points distributor, but this one gives me more advance tuning capability. The distributor included the plug wires which would be WAYYYYY better if I made them myself so the driver side isn't so absurdly long. It'll do for now.

So I've gotta explain why I wanted a new, tunable distributor. This thing has some crazy early smog timing setup. The system is called "Transmission Controlled Vacuum Spark Advance System". In essence there won't be vacuum advance until the transmission upshifts into 3rd gear (and technically Reverse also). When we swapped the transmission, I couldn't figure out why a 72 TH350 would have a wire plugged into it. That wire was connected to a solenoid in the hose to the vacuum advance that would either allow or restrict vacuum.

The vacuum advance is supposed to be connected to ported vacuum. Initial timing is spec'd at only 4° BTDC. The factory knew this could lead to overheating at idle so they had to add another system to compensate for that. I couldn't figure out what this doohickey on the intake manifold was and that's how I found out about this other system.

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That is a "thermo vacuum switch". It has 3 nipples that are connected manifold vacuum, ported vacuum, and the distributor. If the coolant temp rose to 220° or higher, it would connect the distributor to manifold vacuum to increase advance and cool the motor down.

With all that Mickey Mouse, the factory distributor is setup to pull up to 20° of vacuum advance. According to the people over at V8Buick.com, I should be shooting for 30-32° of total timing at WOT all in by 2200 RPM. I felt like another 20° of vacuum advance on top of that at cruise would be way too much (50°+). If I'd converted the points distributor, I would have needed to change out the vacuum advance module too. That put the cost of converting the points distributor over the cost of the new one. Plus everything else is new too.

We've fired it up and locked in the timing. Ended up at 30° total and 12° initial. Just waiting on vacuum hose to show up so we can take it for a test drive. On the Street Demon carb, the manifold vacuum port is on the back of the carb and the ports directly to the manifold are behind the carb as well, so I need a good 18" of hose to get from there to the distributor at the front of the engine.
 
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It's actually quite common on older GM V8s to use 50 - 52 degrees of advance with vacuum at low load cruise.
 
Nice! It looks very familiar. We had to wait 4 months or more to get the TA Performance intake. It's probably a better deal if you can score someone's take off factory 4bbl intake. I was pretty impressed with the peppiness of the 2bbl tho.
 
Nice! It looks very familiar. We had to wait 4 months or more to get the TA Performance intake. It's probably a better deal if you can score someone's take off factory 4bbl intake. I was pretty impressed with the peppiness of the 2bbl tho.
My monte Carlo was pretty peppy with the 307 and 2 barrel carb.
 
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