i was getting ready to tear my engine out of the car. but i have a guy who is interested in buying my exhaust system. he wants to hear how it sounds. i already drained my synthetic oil out of it. would it hurt the engine if i put reg oil in it only to have it run for 3-5 minutes?

 

You should be ok just make sure its full of oil before you fire it up.

 

Wow... Yeah man, regular oil protects engines too. Synthetic has some advantages but please get "conventional oil is bad for engines" out of your head.

You'll be just fine.

 

Deffinatly no problems. I am assumeing you are concerned because some people say once you go sythetic don't go back but event if you believe that a few minutes isn't going to hurt it so you are good as gold!