[South GA 'Stang]

I have used 105 Octane booster and it helps, but when I punch it, I'm still getting a little rattle. Is this something I can live with until April when I have a week's leave and can do a head rebuild? I've looked at upgrading the heads, but I've decided to keep the engine stock as much as possible. Any help is greatly appreciated.

[rodbender]

sound more like detonation, spark knock. Double check your timing. This might help. Does it do it only on firm or hard acceleration?

[South GA 'Stang]

yes, only during hard acceleration

[heavy metal]

run some high octane fuel and recheck the timing....

[Mustang Nazi]

Got to be wrong timing. a stock 72 302 2bbl doesn't have enough compression to need even 93 octane let alone a 105 boost. Head rebuild wont help the problem. Set the timing back a few degrees until it quits making the noise.

[andrewmp6]

Lay off the octane booster before you break the timing chain.