I have a 2001 VS built Speedster. What year engine parts do I buy; Pre-1971, Post 1971? Specifically I'm looking for the bolt on CB Performance Full Flow Oil Pump. They have them for "Up to 1970" and "1971 and on".
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You could look up the year of your engine by the serial number located near the generator/alt but most likely the engine is the '71 up dual port/dual oil pressure relief case/innards. One has a flat gear on cam for the oil pump and other has a concave gear (called dished - this is the '71 up cam). The dished cam can be used in earlier engines so this isn't 100%. Most likely you have a dished cam so get oil pump for the '71 up. Or pull the old pump and check to be certain - before ordering.
Bob; Here's a chart that identifies engine and chassis numbers, by year. Hopes this helps. Art
http://www.thesamba.com/vw/arc...bugchassisdating.php
Flat cam gears have 3 rivets on the cam gear near the center. Dished cam gears have 4 rivets on the cam gear near the outside. Nearly all aftermarket cams use the early style flat cam gear with 3 bolts. Unless you know for certain the engine is 100% original from the factory (highly unlikely), you are going to have to visually inspect the cam gear to determine what you have. If you remove the oil pump, you can look inside and see the cam gear to count the rivets/bolts. You have to buy an oil pump to match the cam.
You can also measure the drive tang depth on the oil pump to tell, but since you have to remove the pump to do that anyway, it's easier just to look at the cam.
So, now I have learned that, in some cases, the chart I posted is useless. As Musbjim says, I learn something every time I visit.
The chart's fine to determine what should be in the engine, but after 40, 50, 60+ years, I don't assume anything is stock unless verified.
As Justin said, it depends on which cam is in the engine, and if the engine has been rebuilt either could be installed, as almost all aftermarket cams are of the 3 bolt (rivet) variety. You need about 1/4" drive tang depth, and a small socket and a vice is the way to adjust it. After the pump body is installed, put the drive gear in (with the drive tang across the gear surface) and measure how much the gear sticks out of the pump.
Art - the chart works if the person that built the car used all parts from same donor (and the engine was original - which is not likely). VS likes to use swing axle chassis (vs new IRS chassis) - either because they are more 356 authentic or they have a narrower rear wheel base. The later engines are a tad more refined than the early 1500 cc single port/single oil relief design - so they are usually used. I suspect VS separately sources chassis, engine and trans so OEM build based chart doesn't help much.