I have no idea why it took us so long to even consider taking a look at this, but it's stuck open. So, while running it without the intake, the car still was running rough. Took a look at the ignition timing(after replacing the timing gears, so it hadn't been set yet) and found it to be off. So, we set the timing to about 12 degrees advanced with the vacuum retard disconnected. Seems to be a bit better.

But, since I like to look at all things vintage volvo, I watched the timing as I revved up the engine... Hmm, no advance! With the vacuum retard connected, once I got to 2500rpm or so the vacuum retard would go away and the timing would advance.

If we leave the vacuum retard disconnected, the ignition timing stays at about 12-13 degrees advanced all the way up to 3000rpm and beyond.

Twisting the rotor by hand doesn't feel abnormal, but I guess there's something funky in there. It's already been taken apart and cleaned up/greased. We have another dizzy that we're taking apart right now...
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Kyle - 244! - Kawasaki Ninja 250R - Oregon Volvo Tuners?