Messed up Timers? Arduino ISP

Hello

Im tried to use a factory-new Atmega328P, since my board does not have a 16MhZ Quarz on it, i can't use a standart Arduino Bootloader!

I read about, that you can upload a sketch to an arduino board (called ArduinoISP.ino) and then use the ISP Pins to programm the factory-new Mega.

Works perfectly!, but i think something is wrong with the timers...because all my time-based functions, like delay(); take much longer

Did anyone noticed this and knows how to fix?

Perhaps you have compiled a sketch for 16MHz, and are using the internal oscillator of 8MHz.
Choose an Arduino board that has 8MHz, or create your own board definition in the file "boards.txt".

How much is "much longer", is that exactly twice a long ?