Another timing curve question

DrCharles said
Mattax, thanks for all the timing info and data. I'll need to chew on that for a while...
I could (when getting all the timing in really quick, if not actually at idle) screw down the adjustment in the vac can so it's basically locked out, then start putting a little back in until ping starts to return...
It's also possible to limit the amount of advance by modifying the stops or the arm, too, 15 may be too much for a fast or locked-out curve as you mention, but even 10 or less would help with part-throttle efficiency.

Take your time chewing that over. I got to get some stuff done today!
It's not the 15* vac advance. That plus 36 is still just 51*. At highway cruise that's fine. The problem is when it comes in. Sure you may be able to delay it so it doesn't contribute until over 12 or 14", but may or may not get full benefit.
Try to think what happens in the combustion and then work back to the timing needs.

Since you have a dragstrip goal, you're definately going to want to test upper rpm timing affects on the mph and e.t.
I'm pretty sure David in St Croix has a similar stroker, but don't recall the cam. Might want to see how he's made out with his timing curve changes. There was a little problem with the drag strip on the island after the hurricanes... he's on moparts and also RFS forums...

DrCharles said
Working on the carb too, although only one thing at a time ;) It's an old #4780 (800 DP). Eventually I'll get tired of screwing with it and get something more modern and adjustable!

Already have 3/32" holes in all four blades, the only way I could get enough air in and keep the transfer slots square on both the primary and secondary. If I could run more than 22 initial timing I could probably reduce or eliminate some of the holes - but I still need to keep the t-slots close to square.

I agree YR - make it adjustable.
I'm surprised you have the secondary t-slots square unless it was converted to 4 corner idle, and even then might not want them square depending on how high up they are.