Jump to content
  • When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.

Distributor Advance Curves


bnam

Recommended Posts

I thought I'd data this thread with the curve for Bosch for distributor model 0 231 180 013 with the vac retarded valve and seems to be only used in the 1974tii.

There seems to be a lack of info on this particular distributor advancement curves curve on the FAQ so I emailed Bosch and this is what they sent me

 

 

 

Bosch curve 1.png

 

Bosch curve 2.png

Along with this message in German.

Hallo,

Verstellkurve anbei. Für Druckfehler übernehmen wir keine Haftung.

Bitte beachten Sie, dass sich die U/min auf die Verteilerwelle beziehen. Diese dreht beim 4-Takt-Motor mit halber Drehzahl. Die Prüfwerte werden auf einem Bosch-Zündverteilerprüfstand ermittelt.

Mit freundlichen Grüßen / Best regards

Matthias Thiess


Google Translate:

Hello,

 Adjustment curve attached. For misprints we accept no liability.

 Please note that the U / min refer to the distributor shaft . This rotates the 4 - stroke engine at half speed .
The test values
are determined on a Bosch Zündverteilerprüfstand .

 Sincerely / Best regards

 Matthias Thiess


So what i am thinking is "sure the doubling the rpm makes sense" but the advancement deg too? maybe?
as the sit in the curve they seem really low..

I emailed the guy back asking but didn't hear anything yet...

 Can anyone that reads/speaks German translate the bottom part of that pic? and may help explain more on what is going on?

I plotted the curve with both numbers doubled and it makes a little more sense but are still way off from the other curves for a tii's on here and in the KF manual

curves.jpg

 

 

 

Link to comment
Share on other sites

On 7/12/2013 at 9:52 PM, bnam said:

Chris,

Good point.  I'm still trying to figure this out - so let's take your distributor as a case in point -- why the Tii vs. the 73 and older 003 distributor?  The 003 has the same centrifugal advance curve as the Tii (if you left the vacuum can unconnected) -- and with the vacuum can connected, you would have the Tii curve plus the part throttle vacuum advance, plus greater advance than the Tii at 3500+rpm.  So what advantage does the Tii disti give your 73 dual carbed setup?  Even if the carbs have no vacuum port, could you not leave the 003 with vacuum can unconnected and still have the same or better curve than the Tii? 

Byas

 

I only bought a tii distributor because my original was tired and I wanted a new dizzy. Honestly, I did not do a lot of research on the advance curves of the various 02 dizzys and now regret that. I always intended (and still intend) to go to a crank fired, direct ignition, and off the dizzy.

Chris B.

'73 ex-Malaga

Link to comment
Share on other sites

  • 4 months later...

What vacuum advance model do I need? My '74 has had a 0 231 188 002 mechanical advance unit since I bought it in 2001.  After a recent long block swap for a '75 engine my local shop is saying the distributor shaft play is excessive and that it needs rebuilding. As the engine is stock other than a Weber DFAV 40 carb, I'm thinking I'll replace it with a vacuum advance unit.  Part number(s) appreciated.

____________________
1974 Golf 2002 

Link to comment
Share on other sites

The reason the tii dist. has less advance is because when you set the timing it starts with more advance at idle.  In every 2002 I have owned/driven I have always felt a straight mechanical advance was better.  AND I feel the M10 motor likes more initial advance.  Vacuum advance does improve gas mileage at light throttle and probably reduces emissions.  These are most likely the main reason the factories used them.  Remember the early 70's?  Unless you design an advance curve yourself the only thing you can control is full advance. 

For timing with any given distributor the only thing that counts is the total advance.  Setting the timing by looking at the ball at some rpm other than at full advance is a waste of time.  The old factory manuals list various rpms for the various models.  This was because in the old days there were no digital timing lights.  Your 2002 is probably about 40 years old.  There is no reason to believe it has the original correct distributor in it or that the advance is correct.  So using the “ball at x rpm” method is not likely to deliver accurate results.  It is smarter to run the engine up to where the distributor is at full advance (usually about 3200rpm) and set the timing.  Of course you’ll need a modern digital timing light.  After setting the timing you can check it by revving the engine higher to make sure you really were at full advance.  After you have set the timing you can plot the timing curve by checking the advance at various rpm’s.

Programmable ignitions are a great thing we'll probably all be using them in the future.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • BMW Neue Klasse - a birth of a Sports Sedan

    BMW Neue Klasse - a birth of a Sports Sedan

    Unveiling of the Neue Klasse Unveiled in 1961, BMW 1500 sedan was a revolutionary concept at the outset of the '60s. No tail fins or chrome fountains. Instead, what you got was understated and elegant, in a modern sense, exciting to drive as nearly any sports car, and yet still comfortable for four.   The elegant little sedan was an instant sensation. In the 1500, BMW not only found the long-term solution to its dire business straits but, more importantly, created an entirely new
    History of the BMW 2002 and the 02 Series

    History of the BMW 2002 and the 02 Series

    In 1966, BMW was practically unknown in the US unless you were a touring motorcycle enthusiast or had seen an Isetta given away on a quiz show.  BMW’s sales in the US that year were just 1253 cars.  Then BMW 1600-2 came to America’s shores, tripling US sales to 4564 the following year, boosted by favorable articles in the Buff Books. Car and Driver called it “the best $2500 sedan anywhere.”  Road & Track’s road test was equally enthusiastic.  Then, BMW took a cue from American manufacturers,
    The BMW 2002 Production Run

    The BMW 2002 Production Run

    BMW 02 series are like the original Volkswagen Beetles in one way (besides both being German classic cars)—throughout their long production, they all essentially look alike—at least to the uninitiated:  small, boxy, rear-wheel drive, two-door sedan.  Aficionados know better.   Not only were there three other body styles—none, unfortunately, exported to the US—but there were some significant visual and mechanical changes over their eleven-year production run.   I’ve extracted t
  • Upcoming Events

  • Supporting Vendors

×
×
  • Create New...