Cardboard-like factory lower engine cover

Mine has little black threaded plastic caps. I'll try and get a picture tonight when I change the oil.
 
Ah, Kurt is right. That is the style of nut that came on my car as well.

This got me wondering where to find such a thing. It took some digging, but I believe I have tracked them down. That looks to be a "Zip Twist" nut, style "JZ". I see references to a 3/16" size and a 1/4" size at the manufacturer's site. Auveco says they have them to fit 6mm studs (close to 1/4" anyway).

https://www.google.com/url?sa=t&sou...MIZ2JsUYlYh_T5hvw&sig2=vPW7KvyyW98YDcMKTWGjQg

https://www.google.com/url?sa=t&sou...me0WaSOIjSeYBkH5w&sig2=SUjOx32-d-El8QC0uI6Qiw

http://m.ebay.com/itm/161800243132?_mwBanner=1
 
Ah, Kurt is right. That is the style of nut that came on my car as well.

This got me wondering where to find such a thing. It took some digging, but I believe I have tracked them down. That looks to be a "Zip Twist" nut, style "JZ". I see references to a 3/16" size and a 1/4" size at the manufacturer's site. Auveco says they have them to fit 6mm studs (close to 1/4" anyway).

https://www.google.com/url?sa=t&sou...MIZ2JsUYlYh_T5hvw&sig2=vPW7KvyyW98YDcMKTWGjQg

https://www.google.com/url?sa=t&sou...me0WaSOIjSeYBkH5w&sig2=SUjOx32-d-El8QC0uI6Qiw

http://m.ebay.com/itm/161800243132?_mwBanner=1

Great find! I'm trying to source another one of those covers so I can fiddle with the installation. After I find one I'll order some of these zip twists and report back...it's probably going to be some time until I try this unless someone decides to try them first.
 
Ah, Kurt is right. That is the style of nut that came on my car as well.

This got me wondering where to find such a thing. It took some digging, but I believe I have tracked them down. That looks to be a "Zip Twist" nut, style "JZ". I see references to a 3/16" size and a 1/4" size at the manufacturer's site. Auveco says they have them to fit 6mm studs (close to 1/4" anyway).

https://www.google.com/url?sa=t&sou...MIZ2JsUYlYh_T5hvw&sig2=vPW7KvyyW98YDcMKTWGjQg

https://www.google.com/url?sa=t&sou...me0WaSOIjSeYBkH5w&sig2=SUjOx32-d-El8QC0uI6Qiw

http://m.ebay.com/itm/161800243132?_mwBanner=1

Hey guys...going to order a few of these to try out. Not near my birds right now, wondering if anyone was be able to check the thread size for these?
 
FYI for future referece, size is 1/4 -28 (fine thread). Bought regular nuts and regular wing nuts for now. Have a couple inquiries out for the ziptwist nuts from Kurt's picture.
 
This is the one on my Anniversary.
View attachment 64046


Kurt...would you be able to take a picture of that wing nut with maybe a quarter coin next to it? Just so I can see the size in a different aspect ratio. I ordered what I thought were OEM (or very close to) nutz, but they seem very small to me! I'll snap a pic of them to share.

Also, I bought one of these engine cover things and it came with the fasteners. Lo and behold, this cover came with a different plastic nut thing and does not use the metal one in your picture. I'll share a pic of it during the week. I get the impression that they may have switched over to the plastic one at some point. Not sure if it was a 94-95 thing or a 96+ thing.
 
By the by...if anyone is looking to source the fasteners for the OTHER side of this cover...where it attaches to the body and not the metal tube, I was able to source them. Old part is on the right.

ZqWmQ54.jpg


1zQF6fu.jpg


ivLEX9v.jpg
 
So, I acquired a lower engine cover for the teal 94. Apparently, at some point instead of using the metal wingnuts pictured in this thread, Ford moved to this plastic fastener. Anyone know when the change to the plastic fastener may have happened? Perhaps anyone with a 94-95 with an engine cover can check and confirm? Both of mine don't have the cover so I cant check.









 
I can't say when they first started using them, but the one on my '95 looks just like the pics Kurt posted and has the black plastic hardware
 
I can't say when they first started using them, but the one on my '95 looks just like the pics Kurt posted and has the black plastic hardware

Thanks IRa!

I have a feeling that the switch took place for 96-97...like many other things. But, hopefully other folks will chime in to confirm. I gotta clean up the cover and will try to install this weekend using the metal ziptwist wing nuts.
 
Sorry for the very long response. I ran across this thread while at home so I did it right away.
metal_wing-nut(20171020_132732).jpg
plastic_front_clip(20171020_132844).jpg

I can also state that my 92 has the plastic replacements for the metal wing nuts.
 
Wow....I've swapped that stuff out so many times with whatever crap I could find at Pep Boys. Why can't they all just standardize on a 1/4" diameter fastener of some type.
 
Cleaned the cover, put new plastic fasteners and used the metal wing nuts. I can confirm they fit just right and are, indeed, the replacement for the OEM wingnuts.

With that said, I'm a little confused at the purpose of this thing :). I figured that it was a cover, like in many other cars, that would prevent splash from the road to come up to the engine bay...but with those wingnuts fastened, it doesn't really cover much more than if there was no cover?? At the end, after snapping the pictures, I opted for removing the wingnuts and letting the cover extend over the metal tube. This car is still seeing some all-weather driving so I would rather have that bit more extra shielding until the time comes when the car will stay in a garage most of the time :)....still ways away from that. At least now I have the little wingnuts.

Anywho, on to the pix!





PS...coincidentally, I found out that the same plastic fasteners used for this cover are the same that are used to secure the clutch hydraulic fluid reservoir.
 
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With that said, I'm a little confused at the purpose of this thing

Airflow thru the radiator (at speed) is exhausted back and down, onto/around the engine, under the body, then out the rear. That flow depends on positive pressure in the nose and negative pressure under the engine sides and rear. The chin spoiler helps set up the negative pressure, and I believe this skirt helps promote positive pressure flow directly onto the engine, rather than letting it dump out right at the front of the engine.

Part of this is for engine bay cooling, along w/fuel efficiency and wind noise reduction, I think, by ensuring a smooth flow in, under, around and behind the vehicle, vs. stirring, stalling, tumbling underneath that would increase resistance. I'm still amazed how quiet my 'Anny is regardless of speed. From flush fit glass to this humble skirt, it would be a shame to have such a wind cheating body shape just to kill the airflow underneath. Note: 700 hours of wind tunnel testing gave the 1989 Thunderbird a 0.31 drag coefficient (better than the '89 'Vette).

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Airflow thru the radiator (at speed) is exhausted back and down, onto/around the engine, under the body, then out the rear. That flow depends on positive pressure in the nose and negative pressure under the engine sides and rear. The chin spoiler helps set up the negative pressure, and I believe this skirt helps promote positive pressure flow directly onto the engine, rather than letting it dump out right at the front of the engine.

Part of this is for engine bay cooling, along w/fuel efficiency and wind noise reduction, I think, by ensuring a smooth flow in, under, around and behind the vehicle, vs. stirring, stalling, tumbling underneath that would increase resistance. I'm still amazed how quiet my 'Anny is regardless of speed. From flush fit glass to this humble skirt, it would be a shame to have such a wind cheating body shape just to kill the airflow underneath. Note: 700 hours of wind tunnel testing gave the 1989 Thunderbird a 0.31 drag coefficient (better than the '89 'Vette).

attachment.php

Heat extraction! Well...good enough reason to me...adding the little wingnuts next time I'm under there :D Thanks for the input bud!
 
Where does one get that little cover. My 90 never had that under my bumper unless that was added on the later years.
 
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