Too much timing, can it cause loss or power even with no detonations?

[mechanicboy]

Too much timing, can it cause loss of power even with no detonations?

I have a supercharged 5.0 and it's tune is set at 24* but I recently added a cooler thermostat and wanted to see if it could take more timing. I used the X3 handheld to add 2* timing. The weird thing is now it goes to 26.5* timing and holds it to at least 7k rpm (shifted early), no timing being pulled from the knock sensors and no detonations detected, well at least when I was checking it which was once.

From what I've read the coyote loves timing, but at what point would I actually start losing power even if there's no detonations? It pulls hard and I can't detect from my butt dyno any loss.

Thanks.

 

[mechanicboy]

To add more information, it runs e85. I ran again tonight all the way to 7500rpm and it went to 27* of timing until it shifted then timing dropped to 25* and started climbing but I had to let out because I was going 90mph already.

 

[toomanytoys]

Absolutely. Too much ignition lead will have the piston fighting against the flame front on its way up the bore. That doesn't mean you're using too much now but the only real way to find out would be on a dyno

 

[mechanicboy]

Absolutely. Too much ignition lead will have the piston fighting against the flame front on its way up the bore. That doesn't mean you're using too much now but the only real way to find out would be on a dyno

Makes sense.