I have just installed the Bosch electronic ignition from a 75 244. While everything works well, and the thought of never to have to adjust the timing every now and then is very welcoming, this unit that I got has a vacuum retard. My points and condensor distributor is a vacumm advance unit. I am guessing the only 75 244 electronic distributors are only available from cars bound for Canada?

Presently, I have the vacuum retard disconnected. Any way of retrofitting the vacuum advance from the old points and condensor distributor?

Many thanks in advance.
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...and the bricks keep on rolling

What's the dwell on the Bosch electronic ignition?
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1980 245 Canadian B21A with SU carb and M46 trans in Brampton, Ont.

Some 240s with B21 and K-jet have vacuum advance AND retard; the vacuum capsule bolts right on the B20 distributor, BUT rotation is opposite, so the B21 retard actuator can be used for advance on a B20.
Don't know if it'll help, though.

That's something worth looking into, since the B20 and the B21 have distributors that rotate in opposite directions. As a matter of fact, the dizzy in the distributor that I have came from a later 240. Goes right in and works well so far for the past 500 miles, so the vacuum advance/retard should be a direct fit.
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...and the bricks keep on rolling

How much total advance does it give?

Vacuum advance is really only needed on B18A, B20A, B21A, B23A, i.e., low compression, small cam, single carb, low performance engines.

I've got a B20A. Sure could use that extra "boost".
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...and the bricks keep on rolling

Vacuum advance doesn't affect full throttle power, only part throttle fuel economy & drivability. The vacuum advance port on a Stromberg is on top, is your carburettor off a different engine?

you're right, its on top.
Seems like everything is running right, so I guess I won't bother with the vacuum advance stuff. I got that port plugged. The idle is excellent, if you have the radio on, you can't even tell its running.
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...and the bricks keep on rolling

Getting the vacuum advance working *might* give you an extra 1 or 2 MPG's, but if it drives nicely at part throttle, than maybe not.

Just check to see if you are getting near 30 degrees of total timing at 3000rpm & you'll have all the power you are ever going to get out of a B20A.

I am guessing the only 75 244 electronic distributors are only available from cars bound for Canada?

All '75 Volvos (and some earlier) used vacuum retard in an effort to meet emmissions testing which was done only at idle. I have heard of a conversion using either a SAAB or 240T vacuum advance but sadly don't remember enough to relay it. Phil over on the 1800 list says the mechanical advance in these distributors (and the ones from the E/ES 1800s work very well with the vacuum retard disconnected, and from my experience with a Pertronix equipped ES he is quite right. I've got a couple of the '75 ignitions but haven't got around to installing them yet so I can't give any hard confirmation.
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Dave Shannon
Durango, CO
'63 P-210
'67 1800s
'88-240
'06 F250 Diesel 4X4
my pages

Currently I am running it with the retard disconnected, but did set the timing pretty high until it pings a little under load, about 20 degrees. Perhaps, I should also mention that we only get one grade of gas over here - 97 octane, so setting the timing that high without detonation is possible.

I did notice a significant differrence with the old vacuum advance distributor when the hose had a leak. Slightly sluggish accelaration was noticable, but car ran OK. I heard air hissing when I pop the hood and hit the throttle, and discovered that the vacuum hose had a crack on it. The hose probably came from Gothenburg with the car.

As for the 75 distributor, other than a more stable idle, it does not feel any lethargic compared to the old one with the vacuum retard disconnected. I did a complete rebuild on the motor, so its hard to say if the extra power is attributed to the new rings or the electronics. I guess I'll be happy with what I have. Just got to get used to the now redundant vacuum port of the manifold.

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...and the bricks keep on rolling