speaking of unobtanium parts..
All the housings are cast blank in that area, that is; solid. California engines had the EGR opening and the holes machined in, the others are left "as cast" I have a picture of both side by side.
Joined: Jun 2008
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From: Chino Hills, CA
Much of the EGR passage from the exhaust ports to the EGR pad is actually cast in; they follow a somewhat serpentine path from down low on the left side up to the top of the mid housing. It'd be almost impossible to machine that passage. The passages from the pad down to the intakes are just straight holes, and are drilled rather than cast.
If you look down into the top opening of an EGR housing you can clearly see the passage is cast, rather than machined.

The pad is machined smooth, but without the opening being cast in there'd be no way to create the passage or to remove the sand used to form it after casting.
If you look down into the top opening of an EGR housing you can clearly see the passage is cast, rather than machined.

The pad is machined smooth, but without the opening being cast in there'd be no way to create the passage or to remove the sand used to form it after casting.
I've never had the valve off mine to actually see the internal passage. From what you say and show, I'd agree it the passage itself must be cast into it. It's possibile they could have used two different center iron castings, but it makes cost sense to use one pattern for both parts. I'll post the pictures later that show a lug or extra material on a 49 state iron where the ERG valve would mount. I would then assume that the lug is machined off on ERG destined irons, exposing the passage and creating the flat surface before drilling and tapping the holes.
Joined: Mar 2001
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From: https://www2.mazda.com/en/100th/
every engine has the cast in land where EGR or the Rx2/3? coolant temp sensor would go, but only the EGR plate has the passages, the other engines would hit water jacket.
i think though that the EGR center iron is the same on the FC, except the FC has the water seals in the wrong place
i think though that the EGR center iron is the same on the FC, except the FC has the water seals in the wrong place
Joined: Jun 2008
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From: Chino Hills, CA
I think the key is the cast-in "NO" tag on the EGR irons, on the rear face above the dipstick hole... Probably standing for "Nitrous Oxide," which is what the EGR system is putatively designed to reduce.
Seems to indicate that they vary at the casting level, not just in the way they are machined. Otherwise, no need to tag them on the casting.
Has anyone ever seen a non-EGR housing with that NO tag cast in?
Seems to indicate that they vary at the casting level, not just in the way they are machined. Otherwise, no need to tag them on the casting.
Has anyone ever seen a non-EGR housing with that NO tag cast in?
Ok, sorry about the size. I copied them and only got what was already posted. A little different than what I remember. It's looking more like you and j9fd3s are correct and the housing castings are unique and different.
NICE score DD!! I assume just (HA! "just" - like these grow on trees?) the one housing? Sorry I can't contribute to the dialogue but wanted to tip the hat to your Unobtainium -ing

Stu Aull
80GS
Alaska

Stu Aull
80GS
Alaska
OMG , its Stu !, thought maybe you got trapped on a chunk of melting sea ice . Figured UNobtanium would get you back on the board .
Joined: Jun 2008
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From: Chino Hills, CA
I got the definitive on its provenance, based on the part number on the box: "1977 12A/13B Intermediate Housing, for use with Automatic Transmission."
The last puzzled me and several others, as to why there'd be a mid-housing variation specific to automatic trans use... Absent other examples from the same year (not likely to turn up), we came to the conclusion that either '77 models only used EGR in conjunction with an auto-trans build, or (more likely) the size of the EGR-to-Intake-Port passage bores were changed according to application, with smaller bores for the auto trans - - which would explain the dimensional difference noted previously.
am **** for Unobtainia - and need to get my keyboard fingers in shape for the summer RX season with all you jokers
;D
DD - hope the housing will do the job. 99% likely it will bolt up with no issues other than the Emission ****'s hounding your ***. Like I am telling you something you don't know my friend.
Stu Aull
80GS
Alaska
Joined: Mar 2001
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From: https://www2.mazda.com/en/100th/
Joined: Jun 2008
Posts: 8,376
Likes: 28
From: Chino Hills, CA
Check out the hand-typed (& misspelled, s/b 'hancock') Mazda shipping label on the box, & the date on the inventory tag:


I'm still on the fence as to whether I should drill the EGR passages out larger to match my original housing; Seems it may not matter to the somg test, based on when the EGR valve opens. Still re-reading.
Completely off-topic: When I did a Google search for that inventory tag ("Mazda Form 120-104") One of the top results was a website on Zoroastrianism with the IP address of 174.120.104.90... which discusses the Zoroastrian creator god, Ahura Mazda, from whom only good things come.
Zoroastrianism is also known as the religion of Mazdayasna, or Mazdaism.

Weird.
Thread Starter
Joined: Oct 2003
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From: Ohio
I had this posted in another thread, but didn't get a whole lot of views, figured I might as well post here since I consider these to be very unobtanium.
It's a full set of badges (sans the sticker on the front bumper) from a 84 JDM only factory 12at - the Savanna Rx7 GT-X Turbo. I've loved the factory turbo first gens forever and it's my dream to be able to import one someday, for now though I'll just have to do with the badges
For reference, the two smaller "Rotary Turbo" ones go on the sail panel in the same spot that our 83 LE badges would be, and the larger "Rotary Turbo" and "GT-X" badges go on the back left where a GSL-SE badge would go.
These cars also had a large "Rotary Turbo" sticker that went on the front bumper below the molding on the right side (our passenger side) of the license plate. I was unable to get that unfortunately.
Anyway, enjoy!

It's a full set of badges (sans the sticker on the front bumper) from a 84 JDM only factory 12at - the Savanna Rx7 GT-X Turbo. I've loved the factory turbo first gens forever and it's my dream to be able to import one someday, for now though I'll just have to do with the badges

For reference, the two smaller "Rotary Turbo" ones go on the sail panel in the same spot that our 83 LE badges would be, and the larger "Rotary Turbo" and "GT-X" badges go on the back left where a GSL-SE badge would go.
These cars also had a large "Rotary Turbo" sticker that went on the front bumper below the molding on the right side (our passenger side) of the license plate. I was unable to get that unfortunately.
Anyway, enjoy!

More Unobtanium for DD - Christmas tree bulbs from Ahura Mazda, Lord of Light and Wisdom:
http://www.oldchristmastreelights.co...lamp_story.htm
http://en.wikipedia.org/wiki/Ahura_Mazda



We used to have those old hand blown and painted tungsten filament bulbs for our Christmas tree, carefully stored away and reused each year since before the war.
They sure were a lot nicer than the China-made LED and microbulb junk they have these days.
http://www.oldchristmastreelights.co...lamp_story.htm
http://en.wikipedia.org/wiki/Ahura_Mazda



We used to have those old hand blown and painted tungsten filament bulbs for our Christmas tree, carefully stored away and reused each year since before the war.
They sure were a lot nicer than the China-made LED and microbulb junk they have these days.
Thread Starter
Joined: Oct 2003
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From: Ohio
^^yeah, maybe too much considering that you can't see them before purchase on ebay unless you go to the seller's residence. the guy didn't even list the color of the panels..
AU $1,950.00 for a pair of door panels, color unspecified??
Are those AU dollars anything like US dollars? I could buy three nice FB's for $1,950.
I know our Australian friends are kind of crazy but I didn't think they were nuts.
Are those AU dollars anything like US dollars? I could buy three nice FB's for $1,950.
I know our Australian friends are kind of crazy but I didn't think they were nuts.
Joined: Mar 2001
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From: https://www2.mazda.com/en/100th/
new door panels, were like $700-900 new, in USD..... back in the day when you could get EVERYTHING, me co-worker was seriously considering ordering new red leather seats for his GSL-SE.
$1500 dealer cost....
those were the days, his car had 4 new GSL-SE wheels, new throttle body ($1600!) among other little various and sundry things under the hood
$1500 dealer cost....
those were the days, his car had 4 new GSL-SE wheels, new throttle body ($1600!) among other little various and sundry things under the hood
Joined: Mar 2001
Posts: 31,837
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From: https://www2.mazda.com/en/100th/
i found a shot of peepers X casting without the block off plate, that hole goes to the cooling system. i used an EGR block off plate to cover it, although i did have to re-drill one hole because its different









