Heya folks,

I'm rebuilding my '82 Trans Am as a result of a recent accident. I ended up buying a stripped '84 Firebird to be my body-parts donor, and I'm wondering if these two years are compatible enough for the:
1. Front clip from the battery trays forward (incl. all 4 frame rails but not incl. wheel wells)
2. Driver's door, rocker panel & rear quarter
3. Glass (windshield and rear hatch)
4. Fenders & hood (temporarily, until I can get some Trans Am pcs.)

My sense from sourcing parts is that 82 & 84 should be compatible, but since I'm also trying to determine how straight my 82 body is, I'm doing some measurements & comparing them to both the diagrams in the 82 shop manual, and to the 84 Firebird itself. Just the strut tower measurement slot-to-slot is different on the two cars.

The strut towers measure 52 3/4" apart on my 82, about 2" over the 1288mm listing in the manual - Is this bad, or normal?? And oddly enough, the 84 has its towers a full inch further apart. So, even though the 84 has no engine, which may or may not bring the towers in or spread them apart, I'm still a bit stumped as to why they'd be 3 inches out of spec w/ no visible impact damage. Maybe the 84 spec is different after all?

If anyone happens to have the 84 Firebird Shop Manual, I'd sure appreciate a copy of the body measurement pages so I could see if they're supposed to be the same as the 82! (Didn't see this info as a sticky but if I missed it, a link would also be appreciated.)

Lastly, anyone know some good shade tree ways to get fairly decent body measurements? A tape measure sags, a tram gauge is too much $, and stiff enough metal rods at 91"+ start being too much as well. My latest conjecture has to do with using one of those digital laser measuring tapes and some plumb bobs dangling a target for the laser. That might take care of all the under-car measurements, still not sure about the engine compartment measurements though. Mine's still got the engine in it btw.

Thanks y'all for any and all help!!
--Mike

 

Aside from a few trim pieces, the 82 and 84 parts are compatible. With over a 2 inch difference from spec on your strut towers it sounds like the car needs to spend some time on a frame machine. I am not sure you would be able to get it straight using tools in your driveway.

 

Thanks 82tarecaro!

I have an open timeframe and plenty of elbow grease, but not too many funds, so this project will likely take a while. I'll definitely get it to a frame shop for final tweaking before paint, but would like to know where I'm at currently. Then I'd like to see about using a body jack/ram to get mine close enough to the dimensions of the donor to start transplanting parts if I'm not too far off.

I found out I measured incorrectly on both the strut tower measurement, and on the spec itself (by 6mm). The strut tower measurement on the 82 is actually pulled in by -19mm, whereas the 84 donor sits at +5mm (assuming same spec for both years at 1282mm), a difference of 24mm. So looks like I'll need to spread my towers by that much (rinse & repeat for the rails) to get all the frames to line up for welding, then bring the finished product back in to spec once assembled. Again, I wonder if the weight of the engine affects this measurement since mine has the engine still and the donor is without.

Hoping for input from anyone else as well...
Is the "D" measurement 1282mm in the 84 shop manual?
Does the weight of the engine normally tend to pull the towers in at all?

Thanks again!
--Mike

 

It will be tough to get good measurements with a ruler. If you are measuring to the top of the strut bolts or studs it will be shorter as the studs are above the tower and leaning in. Without pics and looking at your measurements it looks like the radiator support has been pushed back pulling the upper rails in. Also the front bumper looks to have done the same thing to the lower rails. With the ton of adjustments in these front ends you should be close but those headlights may be tough to get adjusted to fit. I recently repaired a upper tie bar, radiator support with a jerker that actually turned out good. With the radiator removed a porta-power should push the lower rails apart using something to spread the pressure like some thick metal plates so as not to poke dents in the rails from the small ends on the porta-power. Send some pics to get a better idea. F measurement is taken from alignment hole not fender bolt hole. D is measured directly on strut tower, per my manual. All measurements are taken to closest edge. Hope this helps.