Corbeau Forzas installed in my track duty 944. I got them because they are/I am cheap. $200/each + sliders. There is a thread on the 944 board that claims ~1.5 inch extra headroom over the stock seats - I didn't verify.
I was not able to sit in them without my helmet touching the ceiling. I removed the cushion and it was fine. FWIW, I think I sat in the stock seats with my helmet and no problem, but can't remember.
They are tight with the cushion in. I'm 6' - 36" waist. With the cushion out, you gain 1" headroom but they are really tight. They were great on the track however. With the belts I absolutely felt held in.
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Rosewood 1983 911 SC Targa | Black 1990 944 S2 | White 1980 BMW R65 | Past: Crystal 1986 944 na
Guards Red is for the Unoriginal