rgs944

I want to convert my sunroof to manual. Does anyone have any rear clips that prop up the rear of the sunroof when open. Also does anyone know what is a safe speed to drive with your sunroof up. I know 70 or 80 is fine but what about 140? The other thing I thought of is how safe is it to drive at high speeds with the sunroof out. I worry about the rear hatch catching wind from the inside and flying up.

JDS968

I've lately been keeping the sunroof up while driving in the 120-130 mph range, didn't notice any problems whatsoever. If I ever take it up to 140-150 with the sunroof up, I'll be sure to post the results

jpk

Why not just get some replacement gears and fix it properly? I did that four years ago when I first got the 968. I use the sunroof a lot (both the rear vent and removing it entirely) and haven't had any issues.

Clarks has a very detailed writeup. Just follow along and you really can't screw it up; there's nothing complicated about the process at all. Make sure you adjust the slip clutch correctly as per the instructions. It calls for 6 ft-lbs or something; I know mine was way tighter than that when I started; and that's what strips out the gears.

968rz

My 924 has a strap that holds the rear of the manual roof panel to the roof (inside of course) while it's open. Only issue I see is that it's held on by a snap (so it's easy to remove), I wonder if that's enough to hold it at high speeds. Not that my 924 can get to high speeds but I never had a problem.

rgs944

I am trying to get rid of as much weight as I can and I always liked the manual in my 944. Between going to a light weight battery and getting rid of the rear wiper and E sunrooff, that takes a lot of weight off the car right there. It all adds up. 90% of the time I will driving with the sunroof left in the garage anyway. I do not plan on ever selling the car and am trying to make it near the weight of a Club Sport just for more driving enjoyment.

notthd

I may be the only one but in my 87 951 I have had the sunroof "blow" out of the car at 150+."twice" I feel the first time It had weak front tabs. When it went It made a hell of a boom and scared the crap out of me. Not to mention it sailed into a group of trees and destroyed itself.

The second time was due to stupidity. I did not have the rear latched. It was out of the car, weather changed, drop it in just to keep her dry and forgot I had not latched it when I got in to drive.- opps. Hey we all do dumb stuff sometimes. (besides it was 20+ years ago)

Definately make sure the tabs are in good shape.- Cheers, Mike

ramius665

Wow... I had the same thing happen when driving from Tucson, AZ to Nashville, TN. I was somewhere in west Texas driving at ~120mph at night when the sunroof literally just blew out of the car. Still don't know what made it happen, sourced another one from ebay and never had an issue again. And it scared the crap out of me too...

JDS968

Both of these were with the roof down, yes? Not tilted up?

ehall

Never had a problenm at any speed with the top tilted up. Infact I intentionally tilt it up at speed. The wind over the closed roof pulls really hard on it. Opening it equalizes the pressure.

JDS968

I've had a vague suspicion that it might actually create a moderate amount of downforce, spread fairly evenly between both ends of the car. But of course it wasn't designed for that, so it might not work that way in practice.

ehall

My guess is that it probably hurts downforce if anything. For the roof panel to be affected by such a large pressure, there must be a hell of a strong flow over the top. That suggests that Porsche must have done a hell of a good job in the wind tunnel. I would think that any interruption of that flow would hurt rather than help, but that's just conjecture.

notthd

Yes- sorry about the read. Both of these were closed. The pressure created by air flow is very significant and as stated Porsche must have done an excellent job in the wind tunnel. Tilting it up might change flow across the rear spoiler some but just a guess. I now crack the drivers window slightly to equalize the pressure......

Cheers, Mike

Pitou

Hard to believe that a sunroof "blows" out....
There must have been a defect with the latches or the roof was not properly latched.

I have driven mine at 150+, roof up and roof down....never the slightest problem.

notthd

Agreed-

JDS968

I certainly haven't put my car in a wind tunnel...but my thinking was that, assuming the car is creating very fast, smooth laminar flow over the roof [which would be likely to create that pressure differential that would blow out the panel], then the panel, tilted up, should intersect that flow at a significant negative angle of attack and generate some measurable amount of upside-down lift.

And my thinking could be entirely wrong