Anyone know if the sunroof on the touring model reduces the FD's chassis' rigidity and compromises handling?

 

I've never really seen any tests about it, but I believe the touring roofs are a little more reinforced to make up for it (which accounts for the less headroom you have with a sunroofed FD).

I honestly doubt there is that much difference (if any).

 

it ads more weight which slows the car down a bit. The weight comes from the extra support braces need to reinforce the roof when a sun roof is installed. I suppose the extra weight could cause the car to be a bit top heavy....I know this is the case in a first gen but I have never seen figures for an fd.

 

Well, here are the weight differences:

2789 (base model with 5 speed)
2800 (R1)
2862 (Touring with 5 speed)

Granted, all of that 70+ pounds difference isn't in the roof, but I don't see that making the car top heavy or causing any handling problems.

 

probably would even notice figures like that. I think first gens had like 250 more lbs.

 

bose system weighs a lot...so does leather

 

Let's see, Bose system, fog lamps, leather, cruise, air conditioning......I don't see the sun roof as a factor. If weight is a problem just add more boost.

 

OK. I was just wondering if anyone had read anything or heard anything that suggested the sunroof rigidity and hence handling. I hadn't thought about weight distribution.

It sounds as though the matter has not come up before so, even if there is an affect, it must be insignificant.

 

I think it comes down to: Is the roof a stressed member of the car? We all know that on convertibles the frame has to be significantly reinforced because there is NO roof. But if the rigidity comes from the 'A' and 'B' pillars of the car, then a vehicle like the FD would not be affected much if any on having a sunroof in the middle of a non-stressed part of the roof.
From what I have seen, there really isn't any additional bracing in the roof, the added metal is simply the support framing for the sunroof and the drive mechanism.

 

Most sun roofs/moon roofs, are like a tv dinner tray with the mechanics installed and the slapped up to the bottom of the roof.. The support in /of the roof comes from trinagulating the "A" &"B" pillars with the "BOX" sections over the side windows to add strength.. Sincerly, Carter

 

The sunroof assembly on a FC weighs 33lbs or so, this is the complete assembly INCLUDING the roof panel. Figure that there were a few small extra pieces of steel welded to the roof structure to hold the sunroof assy up. So you have to have metal to fill the hole, a good round estimate would be that it adds 30lbs. Not really a big deal.

As for the structure, I agree with the others that commented it really isn't a structural part of the roof. I'm sure it won't be stiffer, but you can't really tell the difference.

T-top cars cut the load path from the A to B pillar, this significantly reduces stiffness. Maybe that is what you were thinking about.

Jeff