work with regular? what would be the effects of using regular gasoline?

do it long enough and you could end up with costly mechanical problems.

don't do it , you put out for a premium vehicle and now want to get cheap ? it's a high performance engine , give it what it needs , if you want to burn regular trade it for a base model civic

it will run poorly and start setting code if it was designed for premium,if it says premium at the filler or on the dash use it or contact the dealer to make sure

It shouldn't hurt anything. It won't have as much power. A guy at work bought an Acura TL used and didn't know it required 93 until about 3 months later.

It will still run, just not a sportingly in acceleration. Cars requiring premium usually have higher compression ratios, which require premium for optimal performance. These cars have sensors which detect the possibility of "engine knock" , and the engine computer will be told to back the timing advance to a safer lever to avoid damaging internal parts. When the timing is "retraded", the optimal performance can not be obtained, i.e., your acceleration will not be as good under these fuel conditions. It may feel a little sluggish in comparison. On some cars you may not notice a huge difference, just depends on how you use the car.