Timing a "unknown camed" engine....

I can almost tell how big a cam is, in an sbm, when I do the T-port sync.
A stocker will require no additional bypass air over the pcv.
A 292 cam will want about .04 to .05 sq inch, which is the equivalent of about a quarter inch round hole,or two 1/8th to 3/16 holes. This is in addition to the pcv.
My 230* likes the equivalent of two holes about 2/32to3/32.I used to drill these holes through the primary butterflies, cuz in my opinion, the idle is smoother, than if the engine gets dry air by secondary cracking.When I used to do that I put the holes up near the low-speed discharge ports. But no closer than 5/16 from the edge of the blades..
To figure out the amount of bypass air I had a pcv hose drilled with different sized holes. I would just uncover/cover the orifices until the engine liked what it liked.It's easy to get carried away with lots of idle timing. But then it can make trouble under load, and then guys might unhook the Vcan. That works for racecars just fine, but for cars that spend huge amounts of time in the idle to 3500 zone, the Vcan is very important;at least to me. Far more important that a few footpounds at WOT, or a smoooooth idle. I'll sacrifice a little power-timing in that zone anytime to be able to run 20* of Vcan. These days, 80% or more of my engine's run time is spent in that zone, so engine efficiency trumps power.If I need more power I downshift and let 'r rip.With 3.55s, 33mph is 2800 in 2nd, and 4500 in first.See what I mean? at 2800 I run about 28* of power timing plus another 20 in the can so that's 48* for fuel efficient cruising. But at go-time the twenty degrees drops out, and at 4500rpm she runs full power-timing, and is sitting right close to peak torque.I run 87E10 with 10.7Scr. The Dcr comes in at about 8.7, and cylinder pressure is 175ish. I run a two-stage curve in an old teener dizzy. 2800 is the knee-point; then it slows down to 32 at 3400.
See, I don't much care what my power-timing is at idle to 2800 cuz theres only one time I'm ever there; namely at WOT, and I'm on my way to somewhere else. How often does this situation appear? Oh, I dunno, once in a blue moon.
From 20 mph on, in first gear, the engine is over 2800, so has all the power-timing it can take, (namely 28*@2800 to 32*@3400).But I am a hammer-down kindof guy at after 20mph, and let the drama begin. Besides with a starter gear of 10.97(manual trans), it blows the 295s away almost right off idle.
If you have an automatic with a 2800TC, same thing.Set the power-timing and advance rate to be correct at 2800 and beyond. Then get the T-port sync set right, and go have fun. Never mind what the power-timing is at 1200, 1600,2000 or 2799.The only time you will be there is when cruising.Then give her as much Vcan timing as, and bring it in as fast as,she will take it.Then you will cruise smooth,and efficient, and save gas.Your rings and oil will thank you for it.
Anyway, that's my opinion, and it works for me.This is not to minimize anything that has already been said or quoted.