you say race engine, but what exactly has been done?
what fuel is it running on and at what point do you hear pre ignition?
all the above means bugger all, just like to ask questions lol!
basically you want to advance it enough to make power and not generate high egt's, but not too far as this can cause pre ignition and melt the engine.
just tweak with it till it's right, but the fuelling will need adjusting to match altered timing.
there is good reason why many would suggest visiting a tuner as they have the experience and equipment to get the best from it in most cases.