For street;
if you do not run the V-can, you are just cheating yourself out of a tremendous amount of free torque, and the potential to make fantastic fuel-mileage.
The curve you build inside the D with the advance weights and springs will NEVER be correct, for anything but running at WOT, and mostly only correct after about 3500rpm; no matter how perfect you make it.........
At all other throttle settings and at almost all rpms below 3500 or so, the curve is dead, dead, DEAD wrong. And is is ALWAYS retarded!
It is the job of the Vacuum Advance mechanism, to try, try, TRY, to get closer to ideal, for more of the time.
Most engines make BEST power, with the Timing adjusted to cause the peak cylinder pressure to be imparted to the crank at a very specific point of the crank's rotation. This is usually about 25 to 28 degrees AFTER TDC. All the timing controls are designed to achieve that, by starting the fire early enough. Under certain conditions, your engine might like over 60 degrees of lead. other times, maybe just 10*. If your D has no vacuum-advance, this is impossible.
For a race engine this is no big deal, because it has just two modes of operation, namely WOT and idle.
But for a streeter, this is not true.
For example, cruising at 65mph-2400 rpm, your engine might be wanting high forties to mid fifties, or more, for Cruise-timing. It wants it, to keep cool, not burn your headers up, and so you can lean it out, and thus get some decent mpgs.
Around town; accelerating normally, the engine might like timing variously between 55 and 35, to make the torque that you are looking for. But if the D is only supplying 25/30, your performance will be sluggish, and she will suck gas, because your right foot is always deep into the carb to find the power to make you happy, AND, you will probably always be in one gear lower from where you should be.
Why is this?
This is because the Peak Cylinder Pressure, is never achieved (until after 3500 at WOT) and what is being made, is always late and chasing after the piston.
How much power is being lost, at these Part-Throttle settings?
IDK, but I'll guess your 360 will feel like a well-tuned 318 down there.
If you have a manual trans;
this is doubly important because there is no Torque-Multiplication of the TC, nor slip, so the engine is married to the tires, at whatever speed they are going.
At 35mph with 3.55s, in 1.40/ third gear, My 367 is sitting at 2200rpm . So cruising around, MY engine is getting 45 degrees and loving it. She's purring right along all sneaky-like being smooth and quiet. But as I lay on the throttle, bit by bit, 22 of those will drop out, to prevent detonation. Finally, at WOT and still 2200, the timing is 23*, nice and safe. A split second later, the tires may slip and if they do, all hell will break loose, lol.
What's yours getting?
