relatively low ignition advance
 

when my car was tuned on the chassis dyno, it made its most power at 26.5 degrees advance at wot. the tuner gave it more timing but it didn't actually make any more power, so he backed the timing off to 26.5 degrees.

does that seem normal? I thought most lsx engines liked around 28 degrees.
i have a 6.0 with milled Texas speed 243s, 228r cam, and 11-1 comp.

My understanding is 243s don't need much advance. If you understand the science ideally we could fire it at TDC but unfortunately the flame takes time to travel, and we have to light before TDC and waste some energy during the compression stroke.

The idea more advance is more power is very 1970s. Modern stuff has more efficient chambers

All depends on the combination. LS1's seem to like more timing than LS2,3,and 7's. I am assuming you have an LS1, typically on the dyno (loadbearing) if they have bolt ons, cam, heads and cam they make the most hp with 26-28 degs. Thats probably the average range but its defiantly not set in stone. I have not seen a stock bottom end LS1 make more hp with more than 28 degs. If your car made peak hp at 26.5 then thats where its happy, I wouldnt worry about it one bit.

The actual timing number borders on irrelevance. If the dyno says that's where its happy, and its making appropriate power for the combo, then that's how it is.

If you want to take anything from it, generally speaking, a motor that makes peak power with less timing has a more efficient combustion chamber.

thanks guys, I wasn't worried about my timing being too low. i was more so just curious as to why my engine was happy with less timing. are the 243 combustion chambers really that much more efficient?

Combustion chamber is good but you also stated you milled the heads and are running 11. Compression cylinder pressure is high and it dosnt require the timing to make the power