E93 Carbon Trunk Install

[doublespaces]

This is the install guide and impressions of an E93 carbon fiber trunk

Intro

Convertibles have a weight problem and since a carbon trunk is a popular weight reduction modification that can also look good I thought it made sense. The problem was the very limited selection of carbon trunks with E93 fitment. Previously you were limited to very expensive options including Duke Dynamics as well as Vorsteiner. This guide will cover the installation of a Vorsteiner rep trunk lid.

The trunk is not a 100% fitment, in fact, it requires a lot of massaging to make it all fit as there are little things you'll need to trim and grind on the interior FRP skin to make things sit perfectly like the lights and fitting the handle. These trims are just excess material left on the interior skins which weren't cut to a T. This isn't too big of an issue as they can be easily trimmed, I'd prefer they cut too little instead of too much because then you're left with a module that doesn't stay in the trunk or is loose. There are several companies that do sell a carbon trunk, this is the one that looked the best for the price I was willing to pay sight unseen.

For those who are willing to give this company a try, here is the listing: https://www.ebay.com/itm/322292253722

When I received it, the trunk came in a very nicely packaged box:

The carbon weave looked pretty good, I'm not an expert with this stuff but I was happy, particularly for the price I paid.



It wasn't perfect however, the corners looked like they had taken a little bit of damage:


Thanks to @Snelson3003 for the tip, buy a good set of Dremel bits: https://www.amazon.com/gp/product/B00T0PQ2TE/


The Dremel Flex Shaft helps get into tight areas: https://www.amazon.com/gp/product/B0000302Y8/


And the carbon dust is no joke, make sure you have breathing protection like this respirator. The bit can jump around, so a bit of tape is good to cushion from those markings:

 

[doublespaces]

Remove Stock Trunk

You’ll start by removing the stock trunk. To do this, you’ll first need to remove the carpet liners using a trim pry tool. Pull out all the plastic rivets.


Use an allen wrench to remove the plastic handle.


Pop out the plastic pieces on the side of the trunk to expose some of the wiring and free up the carpet trim:


Use a flathead to pull the clips off the shock on the passenger side.


When you remove it, you can slip the carpet panel off so it will slide down, and then you can put the shock back on to brace the trunk while you finish removing all the wires.


I do not recommend attempting to remove the center brake light. It is stuck in there real good with a rubber seal and adhesive. You’ll probably break it when you try to remove it, and even if you don’t the rubber gasket is going to need replaced. You can try to save it if you want, but I personally recommend just buying a new light.


The shocks are very powerful, I tucked them down into the car so I could test fit the trunk before securing it down. This turned out to be a bad idea, as they were so strong one of them broke itself from pushing against the interior of the car. So you're probably better off just letting them hang there while you get someone else to help you install the trunk, otherwise you'll be bumping it and scratching things.

 

[doublespaces]

Install Carbon Trunk

When you put the trunk back on, you’re going to have to to work with the hinges a lot in order to get everything lined up. I didn't take any photos of this which is arguably the most difficult part, because its going to be different for everyone. And until you get the trunk latch installed and the wires plugged in, the trunk won't fully seat itself because once it is latched, it will tighten down and everything should come into line. Be careful not to lock yourself out, without the key cylinder installed all you have is the little wire in order to open the latch if you decide to put that in first. I recommend to not close the trunk without having that safety cable within reach to test everything first otherwise you'll find yourself crawling in through the back seat.

On my particular trunk, I noticed it was pinching on either side, getting the trunk situated the right way really made a difference in the fitment.

I found the use of spacers in the hinges can help get things aligned the way they are supposed to be.
The trunk does not come with any of the shock studs, so I had to buy some which were M8 and 10mm in length.
https://www.amazon.com/gp/product/B01NCV053V/


You’ll also need to buy some license plate holder studs, after buying a couple sets I found these work the best: https://www.amazon.com/gp/product/B00AF237UI/


Most of the holes were not shaped exactly right so I had to gradually remove material until the accessories fit into their slots. Be very careful not to overcut otherwise you'll have a sloppy fitting component:


The key cylinder hole itself is largely a complete botch job. Instead of compromising the trunk structure too much, I chose to trim the key cylinder itself. Some trimming was required on the trunk as well:


After doing a lot of little trims, I was never able to get the key cylinder to stick out enough for the cover to clip in, so it will have to be glued or an adhesive used:


The holes for the carpet skin and other push clips will need drilled out, use a bit that is slightly smaller than the stock hood holes:


This is probably my biggest gripe about this trunk:

As you can see here, the three bolts from the brake light have nothing to sink into and be fastened onto. On the stock trunk, there is another layer underneath which the bolts go through, and where I've drilled the three holes in the outter most shell, those are just access ports for the inner nuts. You can see how the holes are supposed to be much larger:


The trunk antenna hole will need cut out, and some of the interior skins will need massaging to have all the modules fit properly.

Once you're done, you should have something like this:

 

[doublespaces]

I received a diagram for the Stabilus 8045YH gas strut. Apparently it has been replaced with part number: 032963.

Extended length center to center 556mm ( 21.89" )
Compressed length center to center 337mm ( 13.26" )

It has an extension(pushing out) force of 230N and the compression(when closing) is 570N.

The ball stud is a DIN 71803 (M8 1.25 10mm). This is the one I bought, but it did not state if it was the DIN spec. Also, the trunk angles these studs the wrong way or the stud heads are shaped slightly off as it doesn't quite seat all the way. I think its just the angle the trunk puts these studs is too steep.

https://www.amazon.com/gp/product/B01NCV053V/

 

[matreyia]

Have you noticed any difference in car behavior dynamically? I was thinking of Duke Carbon Trunk....that stock trunk is insanely heavy.

 

[doublespaces]

Have you noticed any difference in car behavior dynamically? I was thinking of Duke Carbon Trunk....that stock trunk is insanely heavy.

No, I don't really drive the car and definitely haven't taken it through any sort of demanding corners. I have a lot of work to do on it still, in fact i think I'm going to re-bleed the brakes today. Stopping right now is kind of sketch after doing my brake upgrade haha, must be tons of air in there.

 

[matreyia]

Forgot to ask how much lighter this is to stock.

 

[doublespaces]

I didn't weight it, but I'm probably taking it off soon as the fitment around the forward corners isn't quite right. Need to find a way to fix it if possible.

 

[matreyia]

So I take it you removed the carbon trunk? No difference in handling? also, what brand and where on ebay did you get it so I don't end up making the same mistake. I do want a carbon trunk and thinking about vorsteiner.