Tom, How many points on the cage and what is the size of the tubing? My Zcar has a 14point cage and it's 1.5inch diameter tubing, due to the weight of the car. I didn't opt for cromoly at the time, but that is the best way to keep the weight down if you're allowed to use it. With the weight of your car, you might be required to go with 1 3/4 inch tubing.

The material used to make mine came in at 112# total addition to the weight of the chassis.
Mike

 

I believe somewhere I saw a full CF Roof skin. On some cars recieving a full cage I've seen the roofs removed anyway for best fitment, would be a great excuse for a full CF roof. We got lucky and searched high and low and found a factory no sunroof car. I'm anxious to see what the headliner and other interior bits weight as well once you remove them as that's in my plan as well once we go to cup doors and a full cage.

 

Tom, can we see some pics of said sunroof removal and what they used to silicone it in there?

 

working on this, but they are worried interior cabin pressure at 180mph may blow it out if just siliconed in, will let you know the final verdict.

 

will be custom installing according to the NASA rule book which between them, PCA, SCCA, and PBOC seems the strictest because I race with all of them.

 

On what track are you hitting 180 mph?

But yeah I agree, that would likely get blown off which was my first thought when you posted it, but I thought maybe they had another way.

 

I hope you guys don't mind an outsider [me] partaking in this conversation.

Let's remember that oem windshields and oem back glasses are just siliconed into cars.

I siliconed my carbon fiber sunroof plug into my car. I hit 100 mph at least once a day. The sunroof plug has seen 120 mph three times. BTW, I always have my windows closed. The plug has never shown any tendencies of being blown out.

Below is a post from my "Acura TL Diet" thread on the Acura forum. This explains how the plug was installed (including type of sealant used).


Putting the TL on a diet (click here)

No mounting brackets (or other mechanical methods) were used. I felt that using just adhesive to hold the CF panel in place would be adequate. All oem windshields and rear windows are held in place using this same method (adhesive only). Since installing the CF panel, I had my car up to 100 mph on many occasions, and up to 120 mph twice. The panel hasn't been sucked out yet. And, no leaks.







Because I was relying on just the adhesive to affix the panel, I choose the adhesive carefully. I felt this particular product (in the two pics above) would give the best performance. I ordered the adhesive online because no local stores stocked it. I ordered several small tubes (2.7 oz.) and one large tube (Loctite PN# 59375) for the caulking gun (which I primarily used).







With the glass removed, you can see (in the two pics above) the sealing surface that the oem rubber seal presses against. This lip is approx 1/2 inch wide. I constructed the panel to have a matching lip, approx 1 inch wide. The pic below shows the lip (before sanding the edge smooth).





So that once the panel is in position (see pic below), the two opposing lips would form a gap to be filled with adhesive.






Below is another pic showing the gap before filling it with the adhesive.




Before placing the panel in place, 80-grit sandpaper was used to prepare the surface of the panel lip and the roof lip . The sanded areas were then wiped with alcohol to leave a oil-free surface.

Styrofoam blocks (in pic below) were used to support the panel while applying the adhesive and until the adhesive cured.



Before applying the adhesive, the styrofoam blocks were carefully positioned to make sure that the panel was flush with the roof (see pic below).




Below are two pics showing the adhesive up-close.

 

I've read almost all of your thread inaccurate and it's very thorough and detailed.

However we are talking about cars that will see 120-170+ three times a lap for sustain periods 30 minutes at a time 4 times a day for 2-3 days straight. Whatever we do had better be extra solid or it will blow out. I've seen a lot of M3 guys do what you've done and track successfully, but unless It's full proof, not going in my car and I'm sure I'm not the only one.

What would make it full proof is to make what you have but then make a bigger CF panel to bond to the underside of the roof that extends outside of the roof opening by an inch or so then bond the top part to a connection which then fastens to the bottom part somehow.

This way wind will not have a pocket to build up in, it will just come in and flow along the roof line and build pressure in theback window like normal.

 

heavychevy,

Thanks for the feedback.

We weight-reduction fanatics need to stick together and share ideas whenever possible.

 

Have we had anyone give us an approximate weight on the interior carpet (not mats) yet?

Would be nice to see one basically gutted (at least the rear) but with some light carpet doubled side taped in the back to preserve the look of a decent interior. I hate seeing metal inside something other than a full race car. Refuse to drive like that on the street.

I think Markski or someone pulled the carpet and cut it somehow but I can't find the post.


NM I found some of it on page 17 and added it to the main page.

 

What you are contemplating isn't really necessary. Reason is explained by the arrows on the underside of the CF panel. By filling it with a substantial mastic it can, if applied properly, create an undercut surface below the midline. By that I mean the panel can be made fatter at the bottom than is at its midline and hence fatter than the opening in the car. There is no way that it is going to come out at high speed. Also think about the direction of the air forces when 2 windows are down. It is predominantly towards the rear window with secondary flowback across the interior headliner. Airflow at high speed resists change in direction. The flow component across the headliner is more horizontal than vertical and the chance of developing a lot of positive vertical pressure in the headliner area is just about nil.

 

Well if you put it like that, I think it's a great idea. Now just to get the CF panel from somewhere and go through removing the roof cassette.

 

Daytona and its closer to 190.

problem with the CF roof so far is how to keep it from blowing off.

 

my car just went in to have the roof cut off. GD has a CF skin to go on. the interior is being gutted, lexan front and rear windows going in and a NASA race cage.
pics will be on the way and then I will re-way the car.

 

That a boy!!