440 timing?

My engine seems to run better with initial timing in mid to upper 20s- full timing at 38. Everyone keeps telling me I should curve from 17 at idle up to 38. If the engine starts and runs fine, is there any harm in runnnig idle timing high? Is there such a thing as pinging at idle that I need to worry about? (I say Idle, but I mean idle up to the springs starting to spread). The car is just a weekend warrior, no racing, fairly hot street motor though, pump gas, alum heads, roller cam.

hotter cams need more in gear idle advance the bigger the cam the more in gear idle advance it needs till your at full advance at 1000 rpm what makes it idle nice is what you give it!

The open chamber design of the BBM head likes a lot of timing. 38 degrees is not uncommon. But, the open chamber design limits quench with flat top pistons which can lead to detonation. Be sure you don't have any issues with pinging, run good gas, limit compression to 10-1 with steel heads and watch cranking compression. BTW, we only run 32 degrees with a closed chamber 440-1 head. Doesn't make anymore power with more timing.

Quote:

---

My engine seems to run better with initial timing in mid to upper 20s- full timing at 38. Everyone keeps telling me I should curve from 17 at idle up to 38. If the engine starts and runs fine, is there any harm in runnnig idle timing high? Is there such a thing as pinging at idle that I need to worry about? (I say Idle, but I mean idle up to the springs starting to spread). The car is just a weekend warrior, no racing, fairly hot street motor though, pump gas, alum heads, roller cam.

---

Did you verify the timing mark accuracy at TDC when you where assembling the motor if not you may want to now