[Firebob]

Can’t imagine what these big ass bolts are there for. Anybody got any ideas?

[mrennie]

No, but expect a surprise..

Best guess if this is close to the shock mount, it may have broken off and shock connected to trunk floor as quick fix. (My first car, a 72 Lemans, had this "mod" done to it by previous owner then hidden with glued on carpet..floor ended up separating from inner wheel housing!!)

[TedRamAirII]

Whats on the other side?

[Firebob]

No. There didn't seem to be any reason for them at all. They are near the center forward area of the trunk pan. I had one suggestion that they might have been forward anchor points for a trailer hitch. Kind of makes sense since they we're such large bolts but they had splatter paint on them like they were there from the factory. As far as I know trailer hitch would've been something installed by the dealer or after market so there shouldn't be any splatter coating unless the trunk had been recoated afterward. This is a vert so the material you see hanging is what's left of the well liner.

[lust4speed]

I did something similar back in the early 80's to hang a bracket for the electric fuel pump. Seems atrocious today, but back then it was just a quick and easy way to get something done. Thank god I never liked sunroofs or I would have hacked up the roof like a lot of friends did with their cars.

[Tom Vaught]

I also did a similar thing, many years ago), except I had the bolts going to a rubber isolator and then from the isolator to a downward metal bracket that positioned the fuel pumps at the same height as the fuel tank. Jerry Rig at the time but I was a young man in those days. Inside the trunk I had a Fram Fuel Filter bracket and filter and two aero-quip fuel fittings went thru the kick-up. I tried to make it safe but drilled a few holes that were not factory.

Tom V.

[Formulajones]

Yep, the car at one time had an electric fuel pump on it, and being in the center of the pan just above the rearend further confirms that. I've seen many cars done this way over the years.

[mgarblik]

Originally Posted by lust4speed

I did something similar back in the early 80's to hang a bracket for the electric fuel pump. Seems atrocious today, but back then it was just a quick and easy way to get something done. Thank god I never liked sunroofs or I would have hacked up the roof like a lot of friends did with their cars.

X2 on the fuel pump mount. Looks like the bolt spread for a Holley Red or Blue pump. Pretty common place in the old days.

[ELKHORNAOG7]

Could it have been for a heat shield for where a muffler would have been for the trunk and gas tank???---BOB

[Tom Vaught]

I have personally never seen a heat shield for a muffler in that center location.
Maybe on a Firebird with a cross-flow muffler but never on a A-Body vehicle.

Tom V.

[Half-Inch Stud]

Elec Fule pump rubber isolation mounts leave big holes. Need big bolts to cover em up huh.

[Firebob]

Could be they just happened to be the right size to fill the holes I suppose. Pretty sure they were never intended to be there. This is a 67 Firebird. Did they install heat shields between the cross flow muffler and the gas tank? I don't think I've ever been under one that still had the stock exhaust still on it.

[72pontiac]

hate to admit I too did a holley fuel pump that way on my 72. holes are still there I also cut a hole in the floor for a fuel cell sump.

["QUICK-SILVER"]

Any tale-tell signs in the rear wiring where a pigtail was added for trailer lights? Or any extra holes in the rear that don't belong? That is where front mounting was for the stronger trailer hitches. Light duty hitches were rear mount only. HD versions had a brace that went under the tank and turned up.

Clay

[Tom Vaught]

Do you have a picture of that three point trailer mount.

At one time I installed several of the 4 point hitches on A-Bodies and B-Cars.
Know nothing about them F-Bird hitches.

Tom V.

[A Schab]

Looks like the remains from an aftermarket hitch to me. They bolted to the rear bumper brackets then sandwiched the trunk floor between part of the hitch under the car and a piece of flat plate inside the trunk.

[Firebob]

That's pretty much what I've decided they were for. There doesn't seem to be any splices into the trunk wiring or empty holes in the bumper but who knows after all these years.

[Tom Vaught]

Not saying it could not have been a "bolt on" Trailer Hitch but you would not patch in a Holley Blue Pump (for example) to existing wires in the trunk. You would run a new 12 or 10 gage wire for the power and a similar sized ground wire.

Tom V.