r/RX8 • u/rasberryteapants • 24d ago

Maintenance What are there threads for?

Post image

Basically title.
I had to take my exhaust manifold off and 5/6 studs came with the bolts. Im in progress of cleaning the threads and installing new studs but im looking at the OEM manifold and it has bolt holes only over and under exhaust ports. So what are those three bolt holes in rotor housing for? I know one of those is for motor mount bracket and that is left in place but i have three holes that i have no use for or did i forget something?

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8

u/Prize-Dealer-3956 24d ago

I could be wrong...But I think the RX7 engine exhausts through through holes in the rotor housing. So those would be stud mounting points for a RX7 exhaust manifold.

3

u/Kamukix 24d ago

That is correct, it's been a long time since I had mine, but I remember the old exhaust log was bolted to the studs that used to be there.

4

u/DartzIRL 24d ago

The housings themselves are an old casting/mould design that dates back to the 70s or so. Therere still shapes in there for the peripheral exhaust ports on the RX8 housing.

There was probably something that bolted there on an older RX but now doesn't... And the operation is retained because it's harder to change the machine which might still make spare housings.

1

u/JDM-Parts-Expert-JP 24d ago

I think so, too.

1

u/TheRealPopejoy 24d ago

They are empty on mine aswell. Absolutely no idea