Question for those with Vorsteiner type diffusers

[MSUGOGRN]

650 with M Sport owner here and I am in the process of installing some carbon fiber aero parts on the car right now. Part of this is me converting my M Sport rear bumper to an M6 with Vorsteiner style diffuser. Since I had an appointment with the muffler shop this week, I made it a priority to get the M6 and V Style diffusers installed so they could line the new tips up perfectly through the new opening created by the diffusers. Honestly, the process wasn’t too difficult and I will do a write-up on it if others would like (I just didn’t take many pictures) as I did learn quite a few things. In fact, I think I am going to take it back off this weekend and re-do the double-sided tape with some 3M VHB as opposed to the molding tape you can buy at the auto parts stores (I can already see the tape loosening up). My diffuser is from China and while fitment is not 100% perfect, it actually was not bad. I was pretty impressed to be honest.

On to my question: Now that I have the rear diffuser on, I noticed in the center where it wraps underneath the gas tank (the part with the fins) that there is a gap (especially since there is really nothing on the gas tank to attach it to) of maybe 1 or 2 inches. My question for those of you who own this type of diffuser is does yours have a slight gap too? If so, have you ever had any issues with air flow underneath the car? I would love to find a way to attach this to the tank thereby having no air being caught by the inside of the diffuser but I am not sure if that is possible.

EDIT: I don't think I did as good of a job explaining my issue but what I am talking about are the circled areas below. Just wondering how everybody has their attached to the bottom of the car so wind doesn't get caught there. I see that the original has holes drilled in a couple of places but does everything else fit well to car or is double-sided tape used? The first pic is the diffuser I purchased while the second is an original.

[Eurohorses]

I'm surprised you landed a replica piece with such good fitment. I read a few horror stories with the replicas and that's how i ended up going with Vorsteiner. As for the gaps, I have zero gaps on 99% of my rear diffuser. I have about a 1/8th" gap where the diffuser meets the bumper, right under the licence plate. But this is only apparent in the winter months. As it gets warmer, the gap pretty much disappears.

Lets see some pics! Sounds like your car is coming along.

[MSUGOGRN]

Originally Posted by Eurohorses

I'm surprised you landed a replica piece with such good fitment. I read a few horror stories with the replicas and that's how i ended up going with Vorsteiner. As for the gaps, I have zero gaps on 99% of my rear diffuser. I have about a 1/8th" gap where the diffuser meets the bumper, right under the licence plate. But this is only apparent in the winter months. As it gets warmer, the gap pretty much disappears.

Lets see some pics! Sounds like your car is coming along.

Thanks for the quick reply! Yeah...I was pleasantly surprised with the fitment too. I will definitely plan to post some pics after this weekend is over and hopefully I get finished adding the other mods. I edited my previous post to show where I am having a little bit of a gap. It is the section that is all the way wrapped underneath the center of the car.

[Bobby_Drake]

I have an authentic Vorsteiner diffuser, but fitment is 95% at best. This bothers me given the fact that I spent way more $$$ compared to a replica. The holes at the circled area as illustrated by OP does not match despite my diffuser being authentic. I ended up using double sided tape. No issues. Alternatively, you can drill holes and use the fastener clips from your OEM diffuser.

[Eurohorses]

Originally Posted by Bobby_Drake

I have an authentic Vorsteiner diffuser, but fitment is 95% at best. This bothers me given the fact that I spent way more $$$ compared to a replica. The holes at the circled area as illustrated by OP does not match despite my diffuser being authentic. I ended up using double sided tape. No issues. Alternatively, you can drill holes and use the fastener clips from your OEM diffuser.

That blows... and i would have had it out with Vorsteiner if I was in your shoes. At the end of the day, they are all fabricated from molds. And molds are only good for so long. The only issue i have with mine (not Vorsteiner's fault) is that is scrapes on almost every driveway I pull into. The fins being really low, combined with my car being lowered is a really great combo for ruining a $2500 piece.

[Bobby_Drake]

Originally Posted by Eurohorses

That blows... and i would have had it out with Vorsteiner if I was in your shoes. At the end of the day, they are all fabricated from molds. And molds are only good for so long. The only issue i have with mine (not Vorsteiner's fault) is that is scrapes on almost every driveway I pull into. The fins being really low, combined with my car being lowered is a really great combo for ruining a $2500 piece.

My car is stock and I am scraping most driveways. It is inevitable. But life is too short to worry about these things. Enjoy your car!