Vicfreg 771 Report post Posted October 1, 2019 Recent discussion on another thread was about putting speakers in kick panels, where the air vents are. There are differences between the '69 and '70 models worth noting, if you are going to modify your kick panel vents. So, you ask why is there a little vent in the door lock pillar on the 1970's, but not on the 1969's...? For the Mustangs, several things happened....the first was that the vent windows previously used on the 1966-1968 Mustangs were eliminated. Second, on the fastbacks, there are no air extractors. So, with the windows rolled up in the 1969's...not much air moving around. So, if you were smoking say a pipe.....the passenger compartment would look like the "Up in Smoke" movie scene in no time... Ford engineers to the rescue....they invent "Direct Aire" This is a flow through ventilation system. It uses the cowl vents, and a space under the rear seat to allow air to flow into the car, under the seat, through the trunk, and out the one way door lock pillar vents.... Huh? Really? See page 6 of the attached document. (GM had already figured this out and offered the same kind of thing in the Camaro's) So, if you eliminate your kick panel vents in your Mustang, you may have a little less air movement in the car. Unless you have factory A/C, then that handles the issue nicely. ShopTips8-1.pdf 3 lanky, cavboy78 and copb8 reacted to this Quote Share this post Link to post Share on other sites
Hux 45 Report post Posted October 1, 2019 Thanks for the PDF its awesome Quote Share this post Link to post Share on other sites
danno 128 Report post Posted October 1, 2019 Where did you get this old gem of a document? Quote Share this post Link to post Share on other sites
Vicfreg 771 Report post Posted October 1, 2019 Mustang Tek. An excellent site with lot's of info. Particularly good for casting number information. http://www.mustangtek.com/Litterature.html 1 RPM reacted to this Quote Share this post Link to post Share on other sites
fvike 173 Report post Posted October 3, 2019 The Flow through ventilation has one more upside. At high speeds, air is forced into the cabin. This makes the car unstable, because all that air can't get out of the cabin. This is why the early Shelbys, have the lowered top rear window. It ha a vent in it to let that air flow thru, and keep the car stable. The Flow through ventilation does the same job. on a '69 you'd have to open the rear vent windows to get the same effect. Quote Share this post Link to post Share on other sites
Vicfreg 771 Report post Posted October 4, 2019 The early fastbacks had air extractors. Since the Shelby's had Lexan side windows, you are correct, the air had no way out, so they made that cool rear window. The 69 fastbacks had no front or rear vent windows, and no air extractors, so not a good situation. The early Chevrolet's had the same issue, It could lead to a lot of smoke in the car.... 1 Shep69 reacted to this Quote Share this post Link to post Share on other sites
RogerC 136 Report post Posted October 4, 2019 My solution, on each side to be ducted to bottom of rear window. Time will tell how well it works. Quote Share this post Link to post Share on other sites
Vicfreg 771 Report post Posted October 4, 2019 Wow Quote Share this post Link to post Share on other sites
stangman69 17 Report post Posted October 9, 2019 What if I don't have AC and want speakers in the vent holes? What's the problem, beyond general lack of ventilation? I could just crack the windows and solve any problems, right? I am worried a bit about defrost function without AC to dry the air... Nate Quote Share this post Link to post Share on other sites
Vicfreg 771 Report post Posted October 10, 2019 Yes, on the '69s you will have to crack your windows. My advice is to find an old A/C dash, and put Vintage Air in. I didn't do it on my '68 and I regret it every time I take the car out from June to September in North Carolina. 1 stangman69 reacted to this Quote Share this post Link to post Share on other sites