Rain Gutters

Bowie

Bowie

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So I was looking at a photo of a Porsche 959 and I realized they don't have any rain gutters. And they look good.

porsche_100561104_l.jpg

And then I realized my VY commodore doesnt have any and at some point, I suppose rain gutters just stopped.

Anyway now I'm keen to grid the gutters away on my Renault 12 because why not? Well maybe you can help me with the why not. Suggest this is probably the seem that holds the roof on?

Anyway, how crap are rain gutters!
 
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They were quite useful for the good old roof racks and CB radio antenna mounts!

hugo-roof-rack-003-jpg.915967
cte-ss-gutter-mount-large[1].gif


I suspect you'd have to ensure the rubber seals are particularly good if they're all you're going to have between you and rain, 100kph airflow, etc.
 
Nah race car doesn’t matter, just don’t want to leave the roof on the dummy grid.. :p

Fair point about roof racks and cb radios however.
 
I recall back the in the 1980's at an IMSA round, one of the 935 Porches was not allowed to race when the scrutineers noticed the car had no rain gutters. It was OK to have huge wings and rear guards that extended the track to almost twice the standard width but cutting the rain gutters off was an illegal modification to the basic shell. Wind tunnel testing identified the main area of drag was the bit beside the windscreen pillar.
I ran that car in Australia for the subsequent owner and nobody noticed.
There is an aerodynamic advantage over 300 kph so I doubt it is worth the effort Bowie.

If you want to get that type of advantage, just get one of your team to put some clear sticky tape over all the panel gaps before qualifying. Its worth more time than rain gutters at over 300 kph and most scrutineers will not notice the clear tape.
TRIC301.jpg
 
Would you look at that thing. You can totally put a comb through that moustache.

Forget 300km, it just looks cool.

Scrutineers are funny people, but perhaps in was case that it distracted them from the other illegal modifications.

Oh and nice Porsche.
 
I think Bowie is just trying to add some lightness to the car.

I am not sure, but I guess you could check if the roof is spot welded to the cross braces inside. Either way, most of the structure relies on those gutter welds Bowie. And I am not sure you are left with any gains after you cut the gutters off and re-weld the roof.
 
If it's a proper racer, it should have a full roll cage, that is the real chassis, the body is just cosmetic. Take a mould of the roof, cut the steel off and replace it with lightweight fibreglass. Then do the same everywhere, cutting steel out, drill holes in everything non structural that you can find, hinges, brackets etc. As schlitz says, add as much lightness as you can.
 
Yes kid not, this isn't about performance, I'm just obsessed. I'm not noticing them, or noticing them everywhere :p

Good point to check the weld positions on the inside! And yes this thread was just about confirming if I thought I understood how the roof was attached. And looking at it, it seems like a roof, pillar, front and rear windscreen sandwich with overlap made into the rain gutter.

Easy way of lining everything up when building I suppose.
 
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It was the way cars were built back in the seventies. Economy dictates that if you're going to put a gutter you might as well use it hence my suggestion it is going to be structural now that most of the roof welds are in the gutter.

Like I said, I am not sure but my memory seems to have it that the roof cross braces are also sandwiched in the gutter perhaps at the B pillar or something like that. Would be an interesting look to see a gutterless R12.
 
Yes roof cross brace was just bolted between the pillars.

I stuck my head under it today to look for the welds and was treated to all the seam sealer still in place. Der!

From the top however the paint was thin enough, looking at the gutter you can see the spot welds every inch apart.

Anyway added to the list, might be a hectic way to practise my sheet metal welding and grinding.
 
Early 12s had the gutter following the rear door. Later ones had it going in a straight line and it destroyed the cars styling.
 
Until the early 1960's Victorian motorists were required to use hand signals therefore the drivers window was always down in traffic no matter the weather. No gutter would have led to an ingress of water. The gutter allowed an external joint to be made and to be acceptable to the buyer. It was always a roughly finished part of the body and you didn't want to look too closely at the paint.
 
My reno has a gutter because we all once had to use hand signals.

Well there ya go.
 
The R16 got around the need for a rain gutter,
For other cars, it was a convenient and easy way of attaching the roof pressing.
 
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