Problems with AMD firewall install

[moparmike1974]

Im looking for anyone who has installed an AMD firewall in their cuda or challenger that can give some tips on installing.
I started by clamping it from the top and working down. When I got to the bottom there is at lease 1/2" gap to the floor flange. So I pulled it and clamped the bottom and worked to the top. It almost wanted to go but couldnt quite make it. Next I started at the top and clamped it down, working my way to the bottom with the same results. All of curved are lining up on the hinge pillars like they should. It appears that the bottom part just does not extend down far enough.
Has anyone else run into this issue and if so what was the remedy?

 

[budascuda]

I don't have experience with replacing the firewall but I take it that the cab is properly supported, got any pictures?

 

[Adam]

I installed an AMD firewall, it fit very well and only needed a little massage by the windshield corners.
Can you measure the old one and compare it to the new one?

 

[Challenger RTA]

Clamped on. remove and observe the fit and compare fit and measure.Try clamping bottom on first. Did you take pictures before removing? might help.
. Might require hammer adjustment with a block of wood. so really you are of a 1/4 on top and bottom.That is a perfect fit. the way thesis cars are built.

 

[moparmike1974]

Here is a pic with the top in the right place and everything clamped down. There's no amount of stretching, dolly work etc that is going to make these flanges reach.

 

[AUSTA]

Is the floor already welded also make sure the windscreen fit's .

 

[Challenger RTA]

Did you pull any measurements before dissembled? 41 1/8" firewall to font of core support. X marks the spot there about.following the inside of the inner fender. Try splitting the difference. lay the inner fenders in place see if there to high.
You have duct tape right.

 

[moparmike1974]

You cant split the difference. The top goes up and over and pretty much locks in.
The top of the firewall is exactly where is should be. The windshield actually lays on top of the cowl panel which goes on after the firewall. Same for inner fenders.
Basically im looking for someone who has actually replaced a firewall and has ran into a similar problem.

Yes the floor is welded in. The flange lines up perfectly with the rocker panel end caps just as the original did.

 

[Challenger RTA]

Did you pull the measurement?

 

[Adam]

That’s a pisser… if it were mine I would run a strip of masking tape, as a guide, along the bottom of the inside of the firewall and cut the piece/flange off with a jigsaw. I would tack the firewall in place and plug weld the cut off piece to the leading edge of the floor pan. This would/should leave a gap the same width as the masking tape. It would be relatively easy to make a flat patch & butt weld it into place. I would weld it on the inside so it would be easier to dress the weld, plus the carpet will cover any imperfections.

 

[AUSTA]

Looks like it could be a bit in the floor & some in the firewall the 1 i fiited had a gap so i pulled it together with self tappers then welded the hole over when finished dont know if this is any help original after blasting & another where i just changed the top cowl

 

[rklein71]

Unfortunately, looks like you will need to cut the floor or firewall and weld in a filler piece to make up the difference. It looks like adding a filler piece to the floor would be easier.

 

[moparmike1974]

Yes, this is really the only solution I could see as well. Im going to cut the flange off the original with about an inch or so of excess. Then remove the flange from the new firewall. clamp up and mark the new piece for trimming then butt weld it in. Going to do it in two pieces so I can sandblast the original piece first (too long to fit in blast cabinet).
I dont agree with modifying the floor pan. This would put the flange in the wrong place.

 

[budascuda]

ASTA, that's a nice shell !

 

[rklein71]

Yes, this is really the only solution I could see as well. Im going to cut the flange off the original with about an inch or so of excess. Then remove the flange from the new firewall. clamp up and mark the new piece for trimming then butt weld it in. Going to do it in two pieces so I can sandblast the original piece first (too long to fit in blast cabinet).
I dont agree with modifying the floor pan. This would put the flange in the wrong place.

View attachment 92707

Yes, ensure flange is in right place, hard to tell looking at just pics.

 

[moparleo]

Something is wrong. You should not need a filler. As you have obviously noticed, metal moves when it is welded.
Was the floor replaced at the same time as you removed the firewall ?
The firewall and floor should have been clamped together before welding the floor. Hopefully you didn't completely weld the floor in yet as everything should have been just tack welded until final fit was verified.
Since the pillars were not moved and the firewall aligns properly with them, the problem lies in the floor pan.
Hard to go back after welding but it is up to you if you want to patch it or do the work to go back and do it properly
Going to need to cut some welds and move some metal to get the correct fit. The gap you have is way too much to be normal tolerance stack.
Are you doing this metal replacement yourself or do you have someone experienced helping you?

 

[moparmike1974]

How can the floor be in the wrong place? The front flange aligns perfectly with the flange on the rocker end caps, just as the original pan did.
Yes the pan is fully welded in. However, test fitting the firewall before removing the original floor showed the same issue so the problem in NOT the floor pan. Its simply a repro firewall that is not made correctly. Yes I am doing the work myself. Why assume I am not experienced? Well yes its my first firewall but I have done most every other panel with the exception of a roof skin.

 

[moparleo]

So I guess you got the firewall after you installed the floor than. So everything aligns perfectly , yet here we are. A picture is worth a thousand words.
Unusual for AMD to make a panel that is 1" too short.
Have you contacted them with the problem ? Maybe ask the installation center if they have ever had an issue with firewalls and if so what is the correct solution.
They would have the best answer.

 

[AUSTA]

Were the front inner guards removed is it possible the front rails are low causing the floor to pull down

 

[AUSTA]

Normally the panel is stamped in a huge forming press if the bottom was short at the bottom it would miss the fold on the bottom of the panel