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Fri Mar 03, 2006 7:39 pm

After reading a current post I realized a question. How do I know what distributor I have? The van has the crane cams XR700 igntion, without vacuum advance. Im assuming it is the 009. What is the 009 and why is it sooooooo bad. It is running fine but I have not been able to check the advance since I dont have a tach, at least one that reaches beyond 2k. Do I want the vaccuum advance?

Fri Mar 03, 2006 8:05 pm

Vacuum Advance VS Mechanical Advance
by Robert S. Hoover
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A vacuum advance distributor senses changes in the engine's LOAD -- and does so almost instantaneously. Mechanical advance distributors, which sense only changes in rpm, are meant for special purpose applications, such as as drag racing or poorly designed multi-carb set-ups.... or moving a loaded Type II with a 25hp engine.

If you try to use a purely mechanical advance distributor in your daily driver you will have to jack-up the output of the accelerator pump, since providing a jolt of raw gas is the only way you can bump up the rpms, which is the only way you can get the advance to kick in. But before the revs can build up you waste a lot of gas. This plays hell with your fuel economy and shortens your engine's useful life at the same time.

People who run mechanical advance distributors usually have no idea how well their Volkswagen can perform.

When you go back to a vacuum advance distributor you usually see a remarkable improvement in both performance and economy. The performance-change being the typical perception of an engine that is now suddenly more responsive than before. The improvment in economy comes about because you're no longer throwing away most of the accelerator pump's output each time you shift gears or pull away from a stop.

The fact John Muir.... and all the tits & ass VW magazines.... say the mechanical advance distributor is the best thing since canned beer is no reason to assume this is true. Muir advocates any number of things that are incorrect, including many that are detrimental to your vehicle.

I've written about the vacuum vs mechanical distributor situation many times but most people still don't get it. Volkswagen -- and all other auto makers -- use vacuum-advance (or vacuum/centrifugal) because for normal driving such distributors do a better job than a purely mechanical-advance device.

--Bob Hoover

Your type 4 bus is bigger and heavier than a beetle or a gia and needs the extra advance and cooler running that you get with a stock distributor. This is you....

Vanagon Federal 1980-1983 * 2000

Note: This Distributor also fits Type 4 (412) 1974
Distributor: VW 022-905-205S, Bosch 0231 170 093

Timing Set At:: 7.5deg BTDC @ 850-950 rpm (Man Trans), 900-1000 rpm (Auto Trans) w/strobe, vacuum hose connected. (Bentley Table on Page 28.3 incorrectly states with hose disconnected).
Advance/Retard Range: Vacuum: 8-12deg Adv @ 7.9 In. Hg; Centrifugal: 9-14deg @ 1600 rpm, 21-25deg @ 3400 rpm

A 009 only has about 21º of total advance at 3000 RPMs, you need and want more to run as cool as is possible.

You can buy a SVDA from aircooled, CB or Bus Depot new for reasonable money. Stay away from the Brucks.

Sat Mar 04, 2006 10:03 am

So Randy how are you sure I have the 009? Is it because I dont have the vacuum advance unit attached? Could the PO have taken the advance off when they had the XR700 installed or would it not run correctly that way? As you can see the distributors are not my strong point.

Sat Mar 04, 2006 11:32 am

Remove the distriobutor and look at the bosch number on it. that is the sure way to tell.

There are other options out there for centrifical advance distributors and 2 of them are cast, the 010 and the 019, the POS aluminum 009 (that can be had most anywhere for <$50), and the $350 Mallory non-vacuum unilite which is considerably bigger and you would know it was a Unilite.

Lucky guess.

Running a 009 will be kind of hard on your head temperatures and your "drivability" especially in a vanagon since it cannot adjust to the total load ont he engine.

If you need to use it for a while, make sure your time it at 28-30º of total advance when it is all in at about 3000 RPMs. Hook up your timing light and rev it up until it is all done advancing. The exact RPM is not as important as having all of the advance in.