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Timing gear and intermediate shaft the same?



The intermediate shaft sprocket and cam sprocket on the 8V are the same. They need to turn at the same speed since the distributor needs to stay in sync with the cams.
They are different sizes on the 16V. The intermediate shaft only drives the oil pump and I suppose VW sped it up a little bit by using a smaller sprocket to get a little bit more volume for the piston oil squirters.
Personally, I think a light weight cam or intermediate shaft sprocket is a waste of time. They turn 1/2 the speed of the crank and their diameter is small compared to the flywheel or even the crank itself. Remember that rotational inertia is the weight X the distance from the axis of rotation squared (or maybe it's ^3. I don't really remember and I'm too lazy to look it up) Their contribution to rotational inertia is probably on the order of a couple % of that of the crank, flywheel and clutch components. You'll never notice it, although they do look nice!
I've never played with cam timing on a 16V. In general though the effect is pretty subtle and anything over about 4 degrees is IMO overall detrimental to the power curve. The benefit of adjustable timing sprockets is that you can actually adjust the cam to factory timing specs despite several variables that may cause it to vary.
Dan

From: "Rick Kellner" <rfkellner@snet.net>
Sent: Thursday, December 21, 2006 6:50 PM
Subject: Timing gear and intermediate shaft the same?


>I was looking at Autotech's adjustable timing gears for the 16V motor
> and noticed that they have a lightened cam gear on sale for $39.  This
> lightened cam gear does not adjust, it only reduces weight.  They also
> have a lightened intermediate shaft gear for $69.  Won't the cam gear
> work as an intermediate shaft gear?
> 
> Here is the link to Autotech's site showing the gears.
> 
> http://www.autotech.com/prod_engine_camgears.htm
> 
> Next, does anyone have any experience advancing adjustable timing gears
> on the 16V motor?  If so, did you notice any change in torque?  How many
> degrees of advance did you try?  Some of the new gears offer 10 degrees.
> 
> Thanks, Rick. 
> 
> 
> 
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