n8r

I've just recently aquired a '79 that I would like to do some minor restoration to the interior to. I'm curious if a few things are interchangeable between the more rare 79-80 and the 81-85 models.

Door Panels
Center Console
Shifter Boot piece

Also I have a set of snow tires on 13" wheels that are from an 81+ model - when I tried to mount it on my 79 it seemed that my lug nuts were too long. Would a set of 81+ lug nuts allow me to mount the 81+ wheels? If so - does anyone want to sell me a set cheap?

mckinneyml

Most things are the same. However you will notice some slight changes. I will list all of the ones that I know of.

The insturment cluster (someone correct me if I am wrong on this one) from 79 to 83 is the same physical size. 84-85 have a larger cluster and as a result different dash pad that is more triangluar around the cluster. However, the 79-80 cluster is green and 81-83 is amber. 79 speedometer reads up to 130MPH where as the 80-85 reads up to 85MPH. However the measurement ratio (ie # of turns of the speedo cable to MPH) is the same so they are completely swapable with out any modifications.

79-80 have the voltage gauge and tach in one. When you stick the key in and turn to the "ON" position the tach displays the voltage, after you start the car it displays the RPM's of the engine. 81-85 have a seperate voltage gauge.

Also there are three things that plug into the back of the instrument cluster. The speedometer cable and two round plugs which are approximately 1" in diameter with multiple connecting pins that feed all of the other gauges and lights. The speedometer cable is the same for 79-83, not sure about 84-85, but the two round plugs are different. There was a thread how to do a conversion which I will look for and post a link here.

The center console trim that goes around the radio, climate controls and shifter are different on a 79-80(SA) vs 81-85(FB). The SA has the clock in the insturment cluster where as the FB has it on the center console infront of the shifter.

The 79-80 has a different transmission than 81-85 as a result the shift lever is different. As a result the aftermarket short shift levers only work on the 81-85. There have been debates on how to make one for the 79-80's. The shift boots are probably all the same, but please double check about this.

All of the interior pannels are the same, with the exception of the dash pad that I mentioned above about the 84-85 larger insturment cluster. The small dash pannels that go around the steering wheel did change to as I believe 84-85 used square or rectangular switches. The kick pannels (were the little speakers go in the front) and rear interior panels.

Door panels for 79-85 are the same size but the door pulls with the arm rest are different. 79-83 I believe have the top mounting bolt for the door pull below the door release. 84-85 the same door pull/armrest was moved slightly forward closer to the dash and up closer towards the window with the top mounting bolt being to the side of the door release. Also cars with power windows did not have a hole cut for the window crank. Some door panels have a map pocket and some don't. I don't know if that was a year thing, my 80 has them.

Carpet are the same, with one exception. The 79-80's did not have rear storage bins. They have the same floor panels but no holes for the bins. This is just wasted space in a 79-80. So as a result 81-85 rear carpet is cut for the storage bins.

79 have smaller sunroofs than 80-85. The 80-85 are all the same with the screw type open-n-close vs the pop-up that the 79 has. As a result the headliners are different for those that have sunroofs. Also some where along the line the rearview mirror changed and I believe included the addition of maplights. I believe the headliner change with this feature as well to incorporate the larger mounting of the rearview mirror.

79-80 have different bumpers with a steel box channel style. 81-85 have a vinyl cover. The turn signals are were moved to the corners on the 81-85 as a result the lens are different.

The rear tail light lens are smaller on the 79-80 and larger on the 81-85 with a decorative trim piece in the middle connecting them together.

Head lights and head light covers are the same.

Wheel mounting bolt patterns are the same(4x110) with the exception of the 84-85 GSL-SE Models only (4x114.3).

There was at least one veriation on the lug bolt size. The stock alluminum wheels have a longer lug nut than the 83 Special Edition "Snowflake" wheels that I have. I know this because my spare tire has the stock wheel and the lug bolts from my Snowflake wheels are too short too short to mount it.

Spare tire well changed. 79-80 where large enough to hold a full size spare. 81-84 where made smaller to adapt a 2.1 gallon larger fuel tank below. As a result they are limited to a compact spare.

Below is a link to more First Gen history:
http://www.geocities.com/MotorCity/S.../firstgen.html