If you put a vent in your trunk, at least make sure it is on the side of the trunk opposite your exhaust pipe. Otherwise you are begging to have exhaust gasses enter the cabin of the vehicle and poison you. I can't believe they were fitting holes to the trunks of vehicle to keep windows from fogging up. I grew up in Alaska in conditions not dissimilar to Finland and we never had holes added to the trunk to aid in defrosting.

If you are worried about keeping the rear window free of ice and fog, consider, instead, adding a rear window defog grid kit such as those sold HERE. These will clear fog, snow, and ice from your rear window without risking your health.

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Casually looking for a Clifford hyperpak intake for cheap.

Trunks are not hermetically sealed from the factory, far from it. Trunk lid has several large air passages punched along its lowest point just out bound from weather stripping. Also there is a 2â€￾ or a bit larger plastic drain plug with a ¼â€￾ drain hole and additional drains in its metal seam located in lower inner vertical panel that joins with quarter panel between wheel well & bumper.

My car sucks in fumes if I crack a window open with top up from a pair of rectangular 340 stile chrome exhaust tips dispensing their deadly stink into low pressure area directly off the trailing end of trunk, and not into the slip stream as a turndown exhaust tip would when under way. Repairing tail light housings & lens’, replacing their gaskets sealed a gross air leak, previous to this fix, the car was a gas chamber with the top up.

One of this winter’s projects is to construct some sort of air tight and sound proofing barrier between trunk space, and cockpit to slow air migration between both areas and arrest some of the noise from trunk. Ragtops separate these compartments with a fabric well liner that allows a lot of noise and fumes to pass into cockpit. I’m hopeful to make a big comfort improvement with this endever.

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67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

Very interesting thread - thanks for sharing

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Gary from Downunder
2 weeks ago I couldn't even spell mukanic - now I are one!

Yes, as I mentioned earlier, the vent hole is on the passenger side (as can hopefully be seen in the picture I posted). The exhaust is on the driver's side.

The hole/vent has not caused any problems during its 47 years of existence. Whether it is because I don't drive with open window -I really don't know.

Neither can I say for sure whether it has been beneficial in keeping the rear window fog/ice free either as I have no point of reference -the hole has always been there. (I thought it was standard equipment until a few months back.)

I just know that the fresh air that enters through the heater in the front needs to exit somewhere and many cars have built-in exit vents either in the rear of the car (or more seldom, I think) in rear passenger area. I know this old lady is not hermetically sealed, nor will it ever be. But I do know it will be much better sealed than it used to now that the rust holes are gone and new seals will be put in.

Thanks for the hint Reed, All the new cars here have been fitted with it for over 30 yers now I think, but I wasn't awere this window defog grid kit was available aftermarket too. I'll take it into consideration if the rear window causes trouble. Hopefully the rain water leakages into the cabin and the trunk are history now with all the repairs and that will help.

I wish you luck with your project WJAJR, an open-air gas chamber may sound funny, but it is certainly anything but that in practice.