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Volkswagen Timing

Correct engine timing is crucial for getting top performance and life out of your engine. And if your ignition timing is off, your engine's life and performance will suffer. If you engine's ignition timing is retarded too much, you will have a hard time getting your engine to idle, have pronounced "flat spots" during acceleration and have a loss in overall power. If your engine's ignition timing is advanced too far, you'll experience "pre-detonation" which can destroy your engine in no time. It is therefore imperative that you set your VW timing as accurately as possible.

Timing Setting

VW timing recommendations are a often based on your VW's year and model. And if everything in your VW is original and well maintained, this should be fine. But if you are the third owner, and have no idea what your VW came nor what "upgrades" have occurred over the years, you will first need to determine what distributor you are running. Visit The Old Volks Home - Distributor Interchange Bosch To VW Number and look up the part number on your distributor. Then check out the applications and Distributor Parts & Specifications to include the timing recommendations.

If you are running a Bosch 009 "performance" distributor, you will need to set the timing at 30 (32 max) degrees at 3000 RPMs.

Timing the Bosch 009

Marking Pulley

It is entirely possible that you don't have a pulley that matches your distributor and are confused about the markings on your pulley. The first thing to do may be to invest in a laser engraved pulley with degree marking on it. These are great for setting ignition timing, adjusting your valves and they look sharp to boot. Do note that a few low quality ones are marked incorrectly.

If you don't want a fancy modern pulley, you should visit Finding Top Dead Center/Crankshaft Pulley and figure out where TDC is. At TDC for the #1 piston, your crank pulley key should be facing the 9 o'clock position.

Goniometer

Once you find TDC, you can either confirm the marking on your pulley or mark new ones. The easiest way to go about this is to use a goniometer, which is fancy "protractor" for measuring angles. If you don't have access to one of these tools, you can use simple math to find measurements on your pulley.

Finding Degrees:

Arc Length:		Radius = Pulley Diameter ÷ 2 Degrees = (180° x Arc Length) ÷ (Radius × ?)
Pulley Diameter:


Angle in Degrees:

Finding Arc Length:

Angle in Degrees:		Radius = Pulley Diameter ÷ 2 Arc Length = Radius × Degrees × ? ÷ 180°
Pulley Diameter:


Arc Length:

Static Timing

Static timing is a poor man's way of setting your timing. It can be done with light probe or voltmeter and allows you to get to a safe start point, such as when you are setting up your engine for the first time or swamping in a spare distributor while on the road.

If you are setting timing on a new engine, you will need to reset it later on after it's warmed up and you have completed your initial break-in. If you are setting timing on an "old" engine, you should run it to operating temp prior to setting timing.

Tools needed for Static Timing:

19mm box end wrench.
Flat tip screwdriver.
10mm wrench.
A simple test light.

Static Timing Steps

Figure out the specifications for your engine timing. You may need to consult a repair manual or look up your distributor (see above). A Bosch 009 has a static setting of 5 to 7.5deg BTDC.

You may see one of three abbreviations: BTDC, TDC and/or ATDC related to your timing specs.
1. BTDC - Before Top Dead Center. This is a measurement in degrees prior to the engine reaching top dead center. Since the crank pulley rotates clockwise, BTDC is clockwise or to the RIGHT of TDC.
  
  5 Degrees BTDC
2. TDC - Top Dead Center. This is when the number one piston is at its highest point on its compression stroke.
  
  TDC
3. ATDC - After Top Dead Center. This is a measurement in degrees after to the engine reaching top dead center. Since the crank pulley rotates clockwise, ATDC is counterclockwise (past the point that TDC was reached) or to the LEFT of TDC.
  
  5 degrees ATDC
Use a 19mm wrench to rotate your crank pulley clockwise to your timing set point. You can either rotate your alternator pulley or crank pulley directly. If you pass your timing point, turn the crank pulley counterclockwise about 30 degrees and then turn it back clockwise to your set point. Your timing position is set when your timing set point on your crank pulley lines up with the seem at the midline of your engine.
Use a flat tip screwdriver to remove the distributor cap and position it out of the way. You should see a thin machined line at where the cap sat. This is the point were the rotor will point at when the #1 piston is ready to fire, assuming that the distributor drive gear was put in correctly when the engine was built.
Use your 10 wrench to loosen the distributor drive clamp bolt.
Turn the vehicle's ignition switch to the "ON" position. DO NOT ENGAGE THE STARTER! If you accidentally hit the starter, go back and redo step 2.
Connect the ground wire of your test light to a good ground and touch the positive spike to the spade connector on the ignition points. The light should be "ON".
Rotate the distributor clockwise until the light goes out.
Now rotate the distributor Counterclockwise very slowly until the light JUST comes on. Repeat steps 7 & 8 again to ensure you stopped the distributor JUST as the light came on.
Tighten your distributor clamp.
Test your good work by turning the engine 90 degrees (1/4 turn) Counterclockwise and slowly turning it back clockwise. The light should come back on JUST as the degree mark in which you previously had the crank set to gets to the case half. If it does, your engine is now timed. If it doesn't, repeat this entire procedure until it does.
You are now finished setting your static timing and are ready to set your Strobe Timing.

Strobe Timing Your Engine

Once you have determined that your distributor is within specs and functioning properly, then it's time to set the timing. Once you get to static timing set, grab a timing light and get to work.

Tools needed for Strobe Timing:

10mm wrench.
Timing strobe light.
tachometer.

Strobe Timing Steps

Depending on your distributor and engine, you may need to set timing at various depending on engine RPMs. If you are provided with different timing set points and don't have a computerize ignition system, you should set your timing to Total Advance or at the highest RPM spec you are provided with. For a Bosch 009, you will want to set timing to 30 degrees BTDC at 3,000 RPMs.

Connect the tachometer and timing light.
Disconnect and plug the distributor's vacuum lines.
Start your VW.
Use your 10mm wrench to slightly loosen the distributor clamp. You will want to rotate your distributor, but not have it rotate on its own.
Run the engine up to the point where the distributor's advance mechanisms are at full advance as evidenced by the strobe light.
Twist the distributor body to set the timing. This is generally set at between 30 - 32 degrees BTDC (but no more than 32 degrees) for most configurations, including the Bosch 009.
Snug down the distributor clamp, reconnect vacuum lines (if disconnected for timing as specified for your distributor).
Check/set the idle at between 850 - 950 RPMs and take the car for a spin to see how it runs under load.

If you experience any pre-detonation (pinging), retard your timing a degree or two and test drive it again. Repeat this until you have good power without pre-detonation.

Nate's - Timing Your VW Engine

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