67King

They cut sections from the A and C pillars. Then they usually have to lenghten the roof (some folks change the angle of the pillars, but it is rare). They either weld in a section from a donor roof, or fab up a matching panel.

If you just try to weld the hole closed, you are MUCH more prone to warping the panel. Any time you weld, you want to do the whole panel if possible. If you can't, you want to weld near a feature. Now on the 944, it is probably easier than on some cars, because it is close to the edge, which gives support. But it is still hard to get right. I warped the hell out of teh panel on my old car (Merkur XR4Ti) when I did it.

On the weight, I can't answer for the 944, but on the car I did it on, I took out about 40 pounds worth of stuff, but half of it was the structural reinforcement that held the glass when it retracted into the roof. The 944 won't have nearly as big a structure, so the benefit won't be as big (and the fiberglass doesn't weigh that much, either.

xboostx

some pics of mine . i used a 924 roof i got from a local yard.

LS1Porch

When doing those kinds of panel replacements, you have to do a million little spot welds. If you run any kind of a bead you'll overheat the metal and warp it, as you found out.
Of course, that's just general body panel replacement technique. Roofs and hoods are often made of high-carbon steel that's extremely difficult to weld...so even the best technique might not be enough. Maybe with a TIG?

That 968 in the linked thread is hot! But, i kinda like my sunroof. Maybe the OP could install a non-powered seat to gain the headroom? That's what my plans are. Supposedly the early manual buckets will gain you ~1" of headroom.

xboostx

the roof welds just fine with a mig . but there is a shxt load of spot welds!

LS1Porch

I was mainly saying if you were just going to weld in a patch the correct way is to spot weld every 5" until you have the entire opening spot-welded (versus replacing the entire skin).

ritzblitz

I'd imagine he already has some sort of race bucket instead.

future

Hi Patrick

If you want to prevent any distortion whilst welding then go to this website: http://www.frost.co.uk/ and type “Cold Front” into the search. This product does as it says on the tin and I can testify it really DOES work for a very cheap outlay and peace of mind. I buy many supplies from this company and they are nothing short of excellent and if they will not ship to you in OZ then I can always ship to you as they are located close to me

If you buy a new OEM roof skin then spot welding along the new seam is the way to go but if using your donor roof then you are best seam welding ... After cutting the roof skin of both (see from my thread where this was done), then use the putty placed along the top edge. First make tack welds along the joining edge about 2" apart which will reduce the risk of distortion. Once this is done then you can weld the 2" gaps allowing time to cool in between.

Cheers,
Mark

333pg333

Mark,

Thanks a lot. Good site. Wish you were over hear on holiday. I'd pay you to do the job such is your obvious expertise. It's well out of my league. So much so I think I will postpone it as I don't really want to pay a shop to do it. Perhaps on your next holiday down under I'll help with your spending money!!

DanR

serch my rebuild thread i did last year - search mobil 1 cup rebuild