Ported head and bigger valves

[Slantsix64]

so, I dunno if I'm going crazy but, every since I ported my slant six head and installed bigger valves it seems that I been able to add more initial timing With out pinging, can this happen? I do remember that the cylinder head I had on before was choked my motor and wouldn't pull hard after 5,200 with all that casting flaws blocking flowing and un matched ports. The motor has 9:1 compression with 3.55 gears

 

[Killer6]

Can it happen? Sure. Did it happen? I dunno, if Your porting greatly enhanced chamber/cyl. swirl, it would be more resistant to detonation. But a whole bunch of other things could have been affected, signal at the carb's mains at a given RPM etc., running vac adv.? Is that the only change that was made? Quantify what You were/are running base/mech/vac for Us if You would.......

 

[Slantsix64]

Can it happen? Sure. Did it happen? I dunno, if Your porting greatly enhanced chamber/cyl. swirl, it would be more resistant to detonation. But a whole bunch of other things could have been affected, signal at the carb's mains at a given RPM etc., running vac adv.? Is that the only change that was made? Quantify what You were/are running base/mech/vac for Us if You would.......

What's up Killer6!, yes that and I installed a tube header, I was at 12 degrees initial and bumped it up to 14. I'm going to try to bump it up till she pings then back off.

 

[Killer6]

What is the total advance, and at what rpm is it "all in"? Keeping track of what idles/responds best at what initial adv., and what total adv gives the best hp w/o detonation is key, You can tailor the total mech. with an FBO plate set-up or similar technique. Tube headers,..dramatic mod to make along with that head,....both good ones....