I have a 79 with the same issues, the seat back leans too far back, and I could not find any adjustment. If you find anything with the seat disassembly please let me know also

I just pulled the seats out of my 80 last week and i don't see any seat adjustment , except foward and back.I don't think they spent much time on designing a comfy seat for those year vettes. I can't seem to find any seat backs for an 80 either.Would anyone know if the seat backs are the same as the 79's?

I just completely refurbished my '81 seats. There is no intentional adjustment mechanism. When metal hits metal in the hinge, the seat is in it's normal position. Two ideas that may help a little, if you want to invest some time:
1) If you could live with a little less tilt to the seat bottom as well, how about putting small shims between the rear seat posts (where they bolt down) and the floor board?
2) Pop off the plastic hinge covers, remove the seats cushions, loosen the bolts that attach the hinges to the seat buckets. Mine had some wiggle-room, so I pushed the hinge in the direction that would provide the most upright position and then retightened the bolts. My guess is the bolts will loosen enough over time that the hinge position will go back to where it was, but it may help for a while...

I have a 1979.  The seats don't come with any way to adjust the back to make it more upright. The seats are not comfortable the way they came from the factory. Several owners have suggested ways to make the back more angle forward by putting shims under the rear screws holding the bracket to the floor. However,  I just made a small modification to my seats that made a huge difference.  The fix to the problem involves drilling a small hole on each side of the seat frame just below the hinge between the upper and lower sections of the seat back.  If you tilt the seat back forward slightly you can see where the area just below the pivot point. The base section of the seat has an outer and inner part to the metal frame.  In between the outer and inner part of the lower frame is a flat piece of metal that is part of the upper part of the seat.  As you tilt the seat back forward you see the middle piece move between the two fixed parts of the lower frame.  The idea is to drill a hole through the outer and inner frame of the lower part just in front of where the metal piece of the upper segment is when the seat back is in the upright position you want.You don't even need to remove the plastic covers over the hinges to do this.   You then put a pin or screw through the two holes when the seat back is tilted forward.  You do the same thing on both sides of the seat.  When you tilt the seat back up the pins on both side limit how far the seat back tilts back .  You have to take the seat out of the car to get to the inner side of the seat.  I was concerned that it would be difficult to drill the metal.  However, my 18 volt rechargeable drill with a new bit had no problem drilling through the metal seat frame.  The plastic pieces on the side of the hinges won't line up exactly the way the do when the seat back is in the factory position.  However, this is barely noticeable.  You also can still tilt the seat back forward if you do this. This fix really makes a huge improvement in the comfort level of the seats.  

I made nylon spacers for mine they screw to center of bottom seat back frame, top frame sits on top of spacer.. I made them in three pieces so you can adjust the angle of recline.

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Ebo showed me his and I stole the idea from him to make mine.  I used wider pieces of nylon, maybe 1"x7" and laid them on top of the seat portion of the back.  I attached to lips to hold it in place so that it wouldn't slip off.  I didn't trust my seatbacks to not disintegrate when I try to screw them in.  If it holds up great, if not I'll just get a thicker piece of nylon and carve out an area for the spacer to fit over the lower seat back. 

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Dave C..........My mantra: I can not be bought!!      Long and short term leases available.

Personally, I like some of the ideas. I have 80 seats in my 76 and had the same problem. I finally got some wedge shaped foam and put behind the seat. I actually kept putting vinyl note books behind the seat until it felt right and got that thickness of foam. It cannot be seen unless of course you fold the seat forward. 

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This a reply to SMP entry of 9/9/14

|UPDATED|7/15/2015 10:51:51 AM (AZT)|/UPDATED|


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Tony Merrygold, The Open Road

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Great Thank. I'll try and find time to have a look at it over the weekend.

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Tony Merrygold, The Open Road

I have the same problem on my '80.  I split a length of thick-walled hose lengthwise and put it over the lip that the seat back touches.  It is much better now and it can easily be removed.