Loss of strong electric current to coil

[Todi]

I have a question about a dragracing engine without a generator. How big is the loss of strong current to the coil when the battery is not connect to the generator under a race.... 

[Roman]

Power is equal to the square of the voltage divided with the resistance. If you have an alternator you have 14.4 volt and just the battery is 12 volt.
This means you have 44% more power to the coil if you have an alternator. If it is needed or not is another question, I have run without fan belt frequently, but I put the fan belt back on the return so I get cooling and a charged battery.
MSD ignitions are sensitive about voltage drops so make sure the battery is fully loaded.

Run an alternator if you can, small ones from a Japanese car is vary small and light and really cheap at the scrapyards. The loss of power from running an alternator is close to nothing. It is the fan that is robbing power.

[Todi]

Thank you for the reply! I shall see what kind of solution I will go for....