? for those with aluminum heads

[JBeezy53]

Once you installed your aluminum heads could your motor take more initial timing without detonation?
With stock heads my engine could run at 16* or 18* base timing with no problems, now with the aluminums on there they seem to like 20* or more. I'm currently am at 14* but it seemed smoother with more timing. Has anyone else noticed this?

 

[795.0pacecar]

My car took 20º without detonation, but it stopped making power after 15º so there was no point running it that high.

 

[5spd GT]

It not only depends on the head material, but also how good of shape your valve springs are...

Aluminum heads typically come with new valve springs

I ran 14* before al. heads, and ran 16* after...I could run more if I wanted too at the time...

 

[JBeezy53]

Thanks for the replies.

 

[ShortThrow50]

I run 18 degrees with 93 octane and absolutely no detonation. My car actually wants more, but i dont want to get greedy

 

[JBeezy53]

My car feels like it wants more timing but I haven't had it on a dyno so I don't know when more is too much.

 

[5spd GT]

Too much can hurt you...even if you car can take it...

A dyno would be the best way to tell