Question: what ohm speakers for car?
Answer: Generally home audio uses 8ohm speakers and car audio uses 4 ohms or 2ohms. Most likely you car audio head unit or amplifier is going to be designed for 4 ohm speakers, but its OK to use an 8 ohm speaker on them. But 8 ohm speakers on a 4 ohm system only need to be rated at half the output power of the amp.