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Saw the post about the adjustable cam gear and have to agree that $200 for 5% increase in torque is not worth it, depending on what it does to the torque curve. Some modifications give a bump in torque at high rpm, or simply the same torque, but it reaches the plateau sooner. Does 5% increase mean that somewhere on the new torque curve there is a 5% difference, or does it mean that at all points on the new torque curve there is at least a 5% increase. If ipd has dynoed the adjustable cam at X, Y, and Z degrees advance/retard, then does it share the dyno so that someone purchasing the adjustable cam can follow the "blueprint?" Unfortunately, ipd's results on a project car and unlimited dyno time doesn't mean you'll get the same thing from the same setting. The $200 cam only gets you the part, you still pay for the dyno time or else you don't know what advance/retard you should use.
Anyway, if there were a standard rule for advance/retard and torque/hp increase that could be followed blind (without dyno testing), why not simply put in an offset woodruff key that advances/retards the amount you want. Isky sells them (not sure they have them for Volvos). You could make your own. Put a used gear on an old cam, line up the key slots, and then move the gear on the cam so that it advances the gear 4 degrees (or whatever your little heart desires). Look at how the slots line up now. That's the shape of the key that your going to make. Measure it with a micrometer.
Make one with four degrees advance, and you can flip it end for end and you have 4 degrees retard. Make it out of bar stock and cut it to lengths so that you have offset keys to share with your friends. Now, instead of a $200 adjustable cam you have a 25 cent offset woodruff key that is easy to install, never needs adjustment, and is set to the same advance/retard that you would use on the $200 cam.
All you need to know is the secret number. 4 degrees advance? 5 degrees? 4.25 degrees?
Mark Fleming
73 1800ES Retarded a few degrees, so they say.
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