Carbon fibre diffuser on the California 30

Hi, I'm creating this thread to answer a question that Fireman1291 asked me on another thread of a different topic. So this thread is just to avoid taking that other thread off topic.

I was asked to provide some photos of the CF diffuser that I upgraded my 2013 Cali30 with. I just took my car out for the first time this season as our off-season is usually 6-7 months long. I was hoping to take some reasonable photos with my iPhone but the skies were overcast today and the iPhone camera does not sufficient dynamic range to render shadows well, especially against a white car.

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After I got home and saw how bad the iPhone photos were I dug out my digital camera and took a shot inside my garage.

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I also located a photo shot by RevoZport who supplied the side skirt for my car. Their CF diffuser is virtually identical to the Ferrari-branded unit and their photo is obviously of professional quality.

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My dealer is picking up my car for upgrades and service tomorrow and the light is supposed to be better then so I might be able to take better photos using my digital camera. I may also be able to place my original diffuser below the CF unit for comparison.

Basically-speaking, you will notice the CF diffuser matches the CF license plate holder panel but in bright overcast skies conditions, there will be so much diffused glare coming off (especially a white car) that you won't make out the CF weave on the skin, or even know what the parts are made of. It's actually easier to see on a sunny day.

*** NASTY PROBLEM ***

I had a PROBLEM when I made the upgrade.

The factory Cali diffuser design uses 1 wing + 2 fins but each fin is actually in 2 parts. The main part of the fin holds onto the wing and is screwed into the diffuser panel that also acts as an undertray.

Unfortunately, the 2 fins are so long that they each have a small (rather expensive) trailing section that is separately attached to another undertray that is further forward. My diffuser wing and fin assembly was a perfect fit and an easy swap for the original plastic assembly but I had problems fitting the small trailing fins on the undertray further forward.

Those trailing fins came pre-installed in a new undertray and I originally thought that was great because I wouldn't have to fiddle with the fins. Unfortunately when I tried to swap the undertrays I discovered one of the screw holes in the new tray did not align with the car's undercarriage. There was no way to avoid using the screw location. So I decided to swap the fins between the 2 undertrays and use the CF fins on the original undertray.

That's when I discovered the next PROBLEM.

The small screws fastening the CF fins were made of aluminium and their hex-sided heads were all stripped when they were originally installed. There was nothing to grab onto. I had to literally reshape every screw head with small files, partially digging into the surrounding plastic to get at them. After I got them off I had to locate proper stainless steel replacements as the ones from the plastic fins being replaced were also of questionable condition. All of that took a fair bit of work.

I've attached a photo of the (new) undertray that the CF fins came on. Notice the 6 screw locations with the extensive filing marks.

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Thanks Tom. I'll see how the weather works out tomorrow.

 

I manage to take a few extra photos before my car was collected for service.

Here's a comparison shot showing the factory CF diffuser next to the original plastic/ribber one that came with my car. Only the wing and fins are CF. The panel that the diffuser is attached to is not changed - you use the original plastic one that came on the car. The small trailing portions of the fins are kind of silly and very expensive - see the closer view of one.

My RevoZport side skirt was of 1st-rate quality but I do not believe RevoZport makes the small trailing portion of the fin. You can make out the matching weave in the closeup photo.

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IMO, the CF diffuser is nice but is not great value for your money and the little trailing portions are even worse value. You have to buy them separately already installed on a new undertray and the undertray may not fit your car.

Unfortunately, the factory diffuser design was the only design I was OK with. If I were designing the CF version of the diffuser I would have extended the wing, the fins and maybe use 3 or 4 fins instead of just 2, which should result in greater downforce. The Hammann one is of original design and does increase downforce but I didn't like the way it looks. As it is, the factory just lamely made a CF version of the same diffuser - a waste of an expensive opportunity. Oh well.

Hey tom, here are a few shots of my interior. My dealer is finishing a small "upgrade" to the interior. Hope show that when I get my car back in a few weeks.

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Looks good Jimmy. Nice to see you also went for the same mod.

 

I'm guessing what you mean by "k driving season..." but yes the weather has finally turned up here. Now I just have to wait for my car to come back from service. That's OK, I'm busy anyway. Hope to see more photos of your car adventures.

 

Here are some photos showing the fasteners on the standard plastic diffuser.

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As you can see there appears to be 5 fasteners that use nuts and 4 fasteners that are of the body fender screw variety. The screws are made of light metal and you have to be careful not to strip them.

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If you remove the undertray that is holding the trailing parts of the 2 diffuser fins, that opens up enough room for someone of slender build to get his head and arms into the area to reach back and work on the fasteners... but it would be awkward. The diffuser is fastened to the black plastic panel THAT IS AN INTEGRAL PART OF THE BUMPER.

The exhaust system of my car was also being worked on when I swapped my diffuser so my mechanic wanted to remove the rear bumper anyway. The bumper IS a pain to work on.

 

Good eye!

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