DDK - Die Deutschen Klassiker

For road use, even with a 1720 you don't need any louvres. The Carrera lid has a completely different internal shape and the louvres are there, i suspect, to help get cool air to the carbs, that sit higher and are bigger than those on a pushrod engine......The lid is 'ducted". W

i reckon that, with the typical 4" louvre with 10mm free air gap (1000 mm2 per louvre), i'd need 60 louvres to equal one grille opening,,,, to keep them all on the nearly-flat area i can only get 3 columns, 12 max in each column, so 36 louvres.....might have to hope for the best

Forget the maths, just do LOTS.

46 louvres on order, courtesy of ebay....plus plenty of filler

DSCF4672 (Medium) by adrian rendle, on Flickr

DSCF4673 (Medium) by adrian rendle, on Flickr

thats how it ended up: one central panel with large louvres and 2 side panels, all butt welded in, but needed to stiffen the back before i cut out for the side panels....overall, it lost some of its curvature, but it was the best i could do

And wouldn't they look cool with all the tops pinstriped in white. Real hot rod stuff.

I've always favored the Factory's solution for more flow that was realized with the twin-grill lid. But driving a T-1 leaves few options in this regard, leaving one to consider alternatives like louvers, like 'em or not.

After buying a second lid to modify (a second grill and maybe a ducktail...), luck intervened with the opportunity to acquire a '59 GS twin grill lid: wide open and no rain tray made for great flow. And like the fellow said, wet is not an issue as long as your moving smartly.

Still, after awhile, I got bored with carrying a plastic bag/earth magnets cover for when parked, so I built a tray that would flow well while providing protection at rest, all accomplished without any modification to the lid itself (the tray is mounted using the four luggage rack mounts. The fotos below show the result (if I can get them loaded).