I have been reading and snooping around the internet looking for information to help me make the right decisions in adjusting my timing table. I have a vortec headed older 350 block bored 30 over with flat tops. The cam is a howards cam in my signature. http://www.summitracing.com/parts/hrs-110951-08

My goal right now is to try to adjust my cruising area of the table for economy. I ran across some info on saying that older small blocks could handle as much as 50 deg or more in timing under light load cruising. Then here recently I ran across the 98 vortec table on your site and in the table range I would like to tune (70 kpa, 2500 rpm - 373 gears) it has 30 degrees so I am really scratching my head right now trying to establish some limits so I do not make a bad mistake. But is there something I am missing here about the vortec table?

I have been trying to to understand distributors in order to make a sound decision. And I was thinking that if I had a regular distributor and assumed it had 34 deg total and initial timing and a vacuum advance of 10 deg. I would have 44 total at cruising (2500 rpm). But I look at the table and I see around 30 deg. Is a 98 truck set of 0 degree or is there an initial timing I should add?
Or is simple bc my theoretical distributor has not advanced all the way @ 2500 rpm?
Would appreciate any advice or conversation on this topic.

Thanks,