I have an 87 s4 base and i put s5 seats from a gtu into it. I was wondering if the seats would feel a bit higher, and if they are suppose to. Also I wanted your opinions on which seats are better, the s4 or s5, not are turbo seats though.

 

I say S5 seats are much better.

But only because my 91 seems really bucketted compared to my 86 NA, much more comfortable

 

I think they are practically all the same between S4's and S5's. There are 3 different seats that I know of. The base model/sport model. The GXL seats with the lumbar and adjustable head rest. And the GTU/GTUs/Turbo II seats. I think there is one more seat with leather trim that is different from all the rest but I'm not sure about that one.

GXL and TurboII seats come in optional leather too and bolt up fine. There should be two different mounting frame rails for the driver side too depending which model. I think thats all the differences, correct me if I'm wrong anyone else.

 

I put S5 Gtu seats inside my S4 GXL and don't notice that it seat higher. I think the Gtu feels better then my old gxl seat.

 

The seats do sag with age, i notice the same thing on my old TII when i put s5 TII seats in my S4. My old seats had a sag in the seat, you could actually see the dip.