I have the lower, middle, and upper intake manifolds for a S5 RX-7. I put them on my S4 and got pretty decent power gains in the upper RPM band. The manifolds are port matched do that there is no lips to slow down the velocity of the air. This is NOT aggressive porting, it is only to clean up around the runners. I have cleaned them so they look brand new. I can powder coat them if you want for an extra charge. I am looking for 125 plus shipping. Here are some pics, I will put more up upon request.

 

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