2nd Generation Specific 1986-1992 Discussion

Exhaust manifold 3rd hole?

Old 03-07-2011, 05:09 AM
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Join Date: Jan 2011
Posts: 2

1986 RX-7 S4 13B

I just took off my stock exhaust manifold and there seems to be a 3rd hole besides the 2 exhaust port in the engine (13B). It's about the size of an index finger and located just below one of the 2 primary exhaust ports ( below the rear port, I think).

My point is that I want to get a new header either RB, PS, Cork, etc.

But they all seem to only have the 2 exhaust ports on those header and most of them bolts right up to the engine blocking off that 3rd hole.

So, what does it do? Do I need it?

And yes, I'm running 6 ports...
KungLo is offline  
Old 03-08-2011, 07:55 AM
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Join Date: Feb 2003
Location: Miami, Florida
Posts: 1,591

3rd hole is for the EGR
RX7 13B 4 UR AZZ is offline  
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