got a simple way to re-curve distributor ?

want best performance with out hurting engine from it pinging.

can the engine can still be pinging, when i start putting in lighter springs, but not be able to hear it?

68 GYX 440, 9.6 cr (a little high), 906 w/2.14-1.81,cast iron ex. manifolds,XE274 .488/.491 110,2500 stall, 3.23, 3800#, 91 octane is all i can find around here

Everybody thinks differently on timing method. i try to recreata modern ignition curve from a driving car. That means a lotof idle time for a clean burn. 30-40 totalidle with manifold vacuum advance. for the WOT 34 totalis about all i ever need. All in by 3000 or a little sooner. Tune the vacuum pod actuation to the amount of vacuum avalible. The vacuum pod should addat least 10+ .

With my rpm 440 Im at 18+18 at 2800. 12 in the can connected to manifold vacuum for a clean idle burn. manual trans.

My head has been in a marshall amp for 40 years. Hard to hear anything. Silent ping exists. Pump 89 gas will support about 9-9 1/2:1 without worry. Iron heads , Aluminum heads I used never tried pushing the limits.

I build cars that drive not race. Damn spacebar is broken.

What distributor and ignition do you currently have , what is your timing set at now ?

Yes it will ping before you can actually hear it.

still with the stock dist. and still using points for this summer.

i have too light of a spring in it now, so at 1000 rpm's it's already in.

set total at 30 for now till i can go back and change springs. not using vacum advance now.

Mr Gasket part # 925-B lightweight springs.

Works really well in a stock or mild combo.

This is what I found works for me after reading on this board and experimenting for a while.

Unhook your vacuum advance pod. Hook a vacuum gauge to manifold vacuum, and advance the timing at idle until the needle on the vacuum gauge quits climbing. You may need to adjust your idle lower while doing this.

Calculate how much mechanical advance you need the distributor to add by using that initial timing number minus approximately 34 to 36 total. Weld up the advance slots in the distributor just enough to limit the mechanical advance to the number you calculated. A chain saw file works very well to file and adjust the slots once welded.(i.e. 18 initial - 34 total = 16 degrees of mechanical advance.)

Determine what your normal cruise rpm is on the highway. Be sure you use advance springs that allow it to be all in a few hundred rpm below that.

Run a vacuum advance pod hooked to manifold vacuum. They are adjustable in both the amount of vacuum that initiates their advance and in the amount of advance. This takes some experimentation, but start on the lower end of the scale. I found on longer highway trips that I can get a gas knock that doesn't occur around town or on short highway trips. I suspect it's heat building up in the head in places a bit more than it does on short trips. I had to use less vacuum advance to compensate for this.

My slant six likes 24 initial and 35 total. I also run a short throw vacuum advance pod hooked to manifold vacuum. Total timing at idle with it hooked up is in the mid 40's. The timing drops back to 24 when the throttle is stabbed at low rpm, until the mechanical advance kicks in. No pinging, way more power & torque and better economy when set-up like this.

My 493 inch RB likes nearly the same, but a tad less initial and all in at 1800 rpm. It has no vacuum advance. That may change one day.

Down and dirty, fast and easy way. Remove the heavy stock spring and leave the lite stock spring in place. Don't worry about using just one spring. It should run full advance around 24-2500rpm. Dave

those are great suggestions.....i'll try them, thanks