Dude, you posted this in apprentice tokers, and here. Learn where to post. Also, I was holding back from calling you a complete dumbass, but now that I know you're posting this EVERYWHERE....you kinda deserved it dude.
You have a legitimate claim for fraud from the dealership if you have documentation and verification of the sale, sue them and get a free pound of weed. I would first talk to a lawyer, an independent shop that has credible mechanics, and then the dealership that sold it to you. Explain the situation, what you would like from them be it monetary reimbursement or a V6 car like you thought you were buying, then see what they can offer you. If they offer you nothing, say you WILL see them in court and get what you paid for.