Bosch Vacuum Advance Modules

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Page created by T Mar 10th 2009:

Photo by Jacks showing a close up of the Vacuum Advance Module. Note the green 6 degree Sticker and the number 212 stamped on it. Click to Enlargen.

1 Bosch Vacuum Advance Modules:

[edit] Bosch Vacuum Advance Modules:

[edit] How to Identify a Bosch Vacuum Advance Module:

The colour and number on a Bosch Vacuum Advance Module identifies its response to Vacuum.

These figures apply when the Module is used in a 6 or 8 cylinder Bosch HEI Distributor.

Sticker	Static Advance
6 degrees	6 degrees BTDC
12 degrees	12 degrees BTDC

[edit] Static Timing:

The Coloured Sticker on the Vacuum Advance Module determines the Static Advance Figure that should be set.

Sticker	Degrees of Response @ vacuum	Pullrod	Degrees of Response @ vacuum
Blue 6 degrees	0 @ 14 - 21 kpa		19 -23 @ 47 kpa
Red 6 degrees	0 @ 14 - 21 kpa		16 - 20 @ 44 kpa
Green 6 degrees	0 @ 14 - 21 kpa	212	11 - 15 @ 37 kpa
Yellow 6 degrees	0 @ 14 - 21 kpa		11 - 15 @ 37 kpa
None	0 @ 22 - 29 kpa	212	14 - 18 @ 47 kpa
Blue Dot	0 @ 22 - 29 kpa		14 - 18 @ 47kpa
12 degrees	Unknown		12 degrees at full vacuum

[edit] Pullrod Numbers:

The Pullrod number describes the weight of the spring and the length or travel for the Module.

Photo by Jacks showing a close up of the Vacuum Advance Module. The 6 degrees is the static Ignition Timing for the Engine it's used in. The number 212 defines the Spring tension and Pullrod travel. 212 defines the maximum advance and the Module's Sensitivity to Vacuum. Click to Enlargen.