Can anyone identify these semi-pp housings and what they came out of? Currently sandwiched between 84' GSL-SE irons but I don't want to complete this build if they're not compatible. i.e. spark plug location, etc.

Thanks!

 

so afik its like this
1757-10-100 are the 1974 Big Port, Big Font housings
3775-10-100 are 1975, small port, big font
8712-10-100A/8712-10-150A are 76-77 are like this but it says Automobiles between the 13B, and the Mazda
N304-10-100C, 84-85 GSL-SE have a smooth top, which is how you tell its a converter vs thermal reactor
N307-10-100 are the 83-85 JDM Cosmo housings, i think its like the GSL-SE but smaller port?

and then these 78-82? thermal reactor casting, like 76-77, but it doesn't say automobiles. or if you like 8736-10-100A/8736-10-150A

 

so these would be from the HB Cosmo?

if so, any insights as to why they don't have provisions for oil injection?

 

in the US its like 1978 Rx4/5/Repu, which are all carbed so no Metering nozzle in the housing.
not sure what Japan got for the Cosmo

 

okay ... i'm still a little confused. i get that they are pre-SE housings, but i'm trying to figure out what they would have come in. are you saying that they would have been in the later-1978 model Rx-4s and PUs that came here? this is new to me, so i'm curious because i've never seen pre-Rx-7 housings that did not have either the old font/logo or the new font/logo with "Automobiles" with it.

also, since they ran until 1982, what else would they have been in outside the US? i'm only asking this because i was under the impression that the Cosmo (HB) had an option for a 13B that was pretty much the same as our GSL-SEs.

 

i'm not actually sure when and what they ran to in Japan, i'm under the impression that they had something with a 13B in it after 1979, but i could be wrong.
i thought we had the HB cosmo parts catalog, but i can't find it, so maybe not.

maybe we should just say 1978 in the US, and TBD in Japan?

 

ok i found the ~83 Cosmo Catalog, they had the 12A 6 Port, 12A turbo and the RE-SI 13B
there should be an earlier one, 11/81-10/83 but no idea what comes in it

i'm not sure about the car, but the brochures are awesome
Best pic ever?

 

these snippets of the brochure are, indeed, awesome! so thanks for that. i'm not the biggest fan of the HB, but i do respect it's place in history. so as far as i'm concerned, this is the Mazda literary equivalent of [insert significant relic akin to the Ark of the Covenant here].