4 ohm Speaker to a 2 Ohm amp?
What would happen when I installed a 4 ohm speaker to 2 ohm output?
For home system, if you have a 2 ohm out put Amp you'll be able to power almost any speaker out on the market. Due to 2 ohm amp will have no problem power any speaker rate at 4/6/8//16 ohm effort lessly. The only draw back is you might blown the speaker when playing too loud as 2 ohm output could be too much for it. But if you do the reverse to hook up a 2 ohm speaker to a 4 ohm amp then you'll running the risk of over heating your amp as now your amp will need to work twice as hard to push a 2 ohm speaker.
So, apply this logic its should be okay.
Anyone done it with your car that can give me more convincing reason of why I should not do it?
It'll work fine but there ain't no such thing as a free lunch.
Due to the laws of electricity, the amp won't deliver as much power to those 4 ohm speakers as it would to 2 ohm speakers.
As Judge Dredd would say "Da law is da law"!
Or, to put it another way, at the same volume settting as you used to use, they won't play as loud. Initially you may have to kerfutz with the balance/fader controls a bit. Once they're set you should be good to go.
On the positive side, the amp will be less stressed and be a lot happier.