Is it bad to just put regular gas in the car instead of premium?

 

If your owners manual recomends premium then yes it is bad.

 

Yes, it's only a few more dollars per tankful anyway...

(and yes, the owners manual does specify premium fuel for DOHC's, as does the fuel gauge)

 

You want to put premium because of the fact that you have a 10:1 Compression ratio on the engine. The higher the compression ratio the Higher OCTANE fuel you have to run otherwhise you can get engine knock or predetonation of your air/fuel mixture.