A lot depends where you purchased the cam from. If it's a custom grind cam manufacturers grind the cam straight up, unless specified at to point of order.
One of the more popular "billet' timing chains is almost always off when installed dot-to-dot.
2 & 4 degree keys are readily available, although they're actually closer to 5 & 8.
Timing chain sets offering three offsets, +4 , straight up, -4 are usually eight degrees each.
Back in the day magazines made a big deal about advancing and retarding camshafts for improved performance. Most of them recommended advancing high performance street camshafts four degrees. They seldom mentioned that almost all aftermarket shelf grinds had four degrees of advance ground into them. They never mentioned the "four degree" slots was actually eight. So the trend was to install the cam that already has four degrees of advance and advance it another eight by using the four degree advance slot and then wonder why the car ran like poop.
The old normal when hardly any custom cams had advance ground into them was to use a 2° offset key to retard the cam and the 4° advance slot on the timing chain, you'd end up with three degrees of advance.
All the above was figured out with a degree wheel.
|