They're not going to take parts from you, they'll take the car as it is.

JZX wrote They're not going to take parts from you, they'll take the car as it is.

how much will it affect my cars value specifically that it's straight piped? Keep in mind it's a 2016 Malibu and it's stock value is estimated at 13.5

It depends on what type of dealer it is. If it's a no name 1 off dealer they won't care. If it's a big brand dealer (Ford of... Chevy of.... Subaru of...) then they will still buy it as is however they won't give you much for it because they can't sell it on their lot IF the area requires those things to be installed. The know they will take a loss on it as it will be put up for whole sale auction.

To get the most value put the stock stuff back on, they will have to find someone who will want the stuff you have done to it, and that'll be tricky due to people's tastes so they'll see it as a hard sell and give you less. You can sell the stuff you have for it online or something and actually get some money back for them, the dealer isn't going to give you more money because you spent X amount on different, they don't care about that.

Why would you straight pipe a Malibu

Pikachu- wrote Why would you straight pipe a Malibu

It sounds amazing

1. They won't take the parts from you. Either trade as is or just put it back to stock and trade in.
2. If you keep as is, dont mention any changes you've done to the car unless specifically asked about it, no point in telling them if they dont question in.
3. You won't get the KBB value of your car for the trade, they're going to want to make money on it, if anything for the most value I'd recommend just selling your car and putting the money toward your new purchase.