Hi, I am in the process of building a 318 Mopar, 10:1 compression ratio, 270 edelbrock performer plus camshaft, performer intake, 600cfm carb. Will be using torqueflite transmission and a 2.92:1 rear ratio. Engine will be fitted to Toyota pick-up. My question is how much initial advance and total timing must I be using on the ignition system? Thank You, Deon.  

You'll probably be shooting for about 34 degrees total advance.  Find out how much mechanical your ignition provides and subtract that to get initial.  Initial timing means very little in the grand scheme of things.  Its total timing and where it comes in that matters more.  On my 8.5:1 454 I was able to lock out mechanical altogether, so I'm running 36 initial.

You may find that at that initial timing setting you'll have trouble getting it to idle as cleanly as it could.  If that's the case, you may find that limiting total mechanical advance by 5 degrees or so and adding 5 degrees initial to keep the same overall will help immensely, provided it doesn't cause detonation in the mid-range... which it very well may with 10:1.  That much compression with that mid-range cam might make some intensely high cylinder pressures in the midrange, so take care to not have the curve come in too early.  You have plenty of revs in the engine if you chose heads wisely, so hold off the mechanical advance until at least 3000 rpms.

Those are just ballpark guidelines.  The truth is, there are thousands of factors in just exactly what timing you can use.  Its based on vehicle weight, transmission, rear ratio, quality of fuel, swirl of the intake charge, aluminum or iron heads, cam duration and LSA... the list goes on.  If you really want to get a proper ignition curve, enlist the help of a guru with a Sun distributor tester and a day to play and tune.

For now, stab the stock distributor in it and set it to factory specs.  That will net you about 34 total.  It might run like junk, but it should keep detonation at bay long enough to hook up with someone to tune it.  In the long run, get an adjustable vac advance and a spring kit.  Always hook the vac advance to a ported source (not venturi or manifold) and tune the mechanical first; then add vacuum.