My sunroof is getting cancelled!

[Steve W]

Originally Posted by $yncro

Looking good man! What are the sizes of those wheels? Filled up the wheel wells nicely.

Thanks! They are Fikse FM10s 8.0x17F and 9.5x17R. Tires are 245F 275R.

Originally Posted by Jonny042

Steve, your car is looking great! Can't wait to see it all done.

Not all carbon parts are made the same, and just like fiberglass, there's a huge variety of construction methods and stiffness/strengths possible. There's a lot of flimsy garbage out there. Plastic trash bin is a good way to describe it!

I've built a carbon roof for my latest project that I will be able to stand once it's bonded in. The carbon roof structure weighs about 3000g (6.6lbs). I've seen skins advertised as light as 1.2kg. That would be great for a race car. I'm guessing that's the sort of construction that you pressed on at the body shop.

Nice work! The Dansk steel replacement I had measured 20 lbs, so being that the carbon roof would have to bond with a framed portion of the original steel roof, maybe 3-4 lbs of it, plus bonding adhesive, the savings would be possibly 9 lbs?

[Jonny042]

Originally Posted by Steve W

Thanks! They are Fikse FM10s 8.0x17F and 9.5x17R. Tires are 245F 275R.



Nice work! The Dansk steel replacement I had measured 20 lbs, so being that the carbon roof would have to bond with a framed portion of the original steel roof, maybe 3-4 lbs of it, plus bonding adhesive, the savings would be possibly 9 lbs?

Nope... not even:

"My measurements and calculations tell me if I was to remove the roof skin from a non-sunroof car, that piece of steel would weigh 13.5 pounds, so about double that of the carbon skin."

I would never cut a steel roof off a non-sunroof car and replace it with carbon, the weight difference simply isn't worth it if you are starting with a NON-SUNROOF car.

I do plan to make a slightly lighter skin. It probably doesn't NEED to be strong enough to stand on LOL. The lighter skin should be in the range of 4-1/2 pounds, and bring the weight delta to a steel skin to the 9 pounds you suggest.

The real advantage of the carbon roof would be the weight savings combined with the lower cost of the part, ease of shipping, and ease of installation/less labor cost.

[Steve W]

This week's update. The roof is painted. At the front the roof is painted all the way down the cowl sheet metal/wiper section to where the plastic seals are at the front fenders, so there is no paint blending or transitions to worry about, and at the rear, C pillars, the paint perfectly blends to the existing. Around the door frame and rear windows, the paint is continuous around and under the gutters, which will be covered with new rear window seals and the new headliner/existing door gasket.









And a new headliner ready for installation:



And two layers of Siless 1/4" closed cell foam lined along the inner roof for sound absorption and some thermal insulation. The gaps between panels are for the clearance of the steel headliner rods, which on install, rest tight against the roof.

[Kevin Stewart]

Nice!

[Duc Hunter]

Steve…..looking great. I bet you can’t wait to get her back!

Have whoever does your windshield give us a blow by blow of how he gets the trim shaped so there is no leakage. Lots of recent threads of people struggling with that.

[DonNewton]

At 6'4", I would love to have this done. My issue is I'm the original owner of a 1983 sunroof car. The only type that was available in April 1983. This car was what I wanted once I saw Le Mans in 1971 with Steve driving his 911 through the outskirts of Le Mans. Just can't bring myself to either sell and locate a non-sunroof car or chop mine up. After 42 years, it has become part of me, I guess. The sober part. . .

[Steve W]

Originally Posted by Duc Hunter

Steve…..looking great. I bet you can’t wait to get her back!

Have whoever does your windshield give us a blow by blow of how he gets the trim shaped so there is no leakage. Lots of recent threads of people struggling with that.

After talking to Tyson Schmidt, I've decided I'm going to fit in a new 993 windshield. This would accomplish two things, reduction of wind noise from the flatter seal, and stiffen the chassis overall because the windshield should act as a stiffening diaphragm for the chassis, because it is bonded to the frame with windshield urethane, vs the original windshield is just floating in a rubber seal. Since the windshield needed would need to be the antenna version, and I'd want it with the green tinted strip on top, that glass would actually be less expensive than an antenna version for G-body. The windshield installer, Frank from New Era Auto Glass here in Los Angeles has probably installed thousands of 911 windshields over the decades, and has done many 993 windshield installs in G bodies and he's the only one myself and Perfect Lines would confidently trust in this kind of install. And if it ever needs to be replaced, Frank says it's easy for him to cut out and reinstall a replacement, just as any modern car today.

Although if I wanted to install the original type windshield for a G-body, we had a discussion about that and he did say regarding the rubber seals, they all fit different (factory Porsche, German made, URO, etc.) and the only one he trusts and uses is the German made from a supplier such as SSF.

In any case, when the windshield is installed, I'll upload pics.