Osirus9

iTrader: (10)

I know this has probobly been answered somewhere, but I just can't find it.

are all housings for s4's the same? some people say that there are differences between the front and rear housings, but I never knew if that was true or not.

another thing I thought was that the s4 T2 and NA housing were the same, with the rotars being different, but still interchangeable.

can anybody confirm/deny this info?

87 t-66

iTrader: (133)

the NA housings have diffusers in the exhaust sleeves. the housings are marked for front and rear but im not sure if there is a difference

Osirus9

iTrader: (10)

https://www.rx7club.com/2nd-gen-archive-72/removing-swapping-rotor-housing-exhaust-sleeves-401058/

this confirms that there are indeed differences between the NA and T2 housings.

but I still would like to know if the front and rear housings are interchangeable.

HAILERS

The difference b/t front and rear housings on a series four are the passages for the air from the ACV to the exaust sleeves/diffusers. If you swap front to rear and rear to front then there is NO passage for the ACV air to the catalytic converter other than that split air pipe which does NOT do the same job as the air to the exaust ports/sleeves/diffusers/you pick one or the other for a name.

This difference is SHOWN in the Training manuals that NZCONVERTIBLE made available to this site. Other than that, no there is no other difference than the stamp F or R.

https://www.rx7club.com/forum/showth...ght=photobucket

http://www.wankel.net/~krwright/fil.../parts_manuals/

http://wombat.sevarg.net/RX7/RX-7_Training_Manuals/

http://www.cochran-racing.com/FSM/index.html

Osirus9

iTrader: (10)

so if I have no ACV, or any emissions for that matter, then there is no reason to worry about swapping the housings?

Sideways7

iTrader: (7)

No, you are fine. My NA actually used 2 front Turbo housings and it worked just fine. The turbo housings do have an extra coolant passage that you need to plug if used on an NA, though.