[wicked93gs]

Here is what it should look like(ignore the floor pan work). People will sometimes weld in a piece of sheet metal in the opening.

 

[C6ZZGT]

I have a 1965 couple and where the rear upper back seats are there is a welding in piece of metal covering the opening. I know its not oem so I want to know what an oem back seat area looks like with the seats out and the concours guys are the ones that would know.

Thanks

Picture of yours would help

 

[jws66m]

Here is what it should look like(ignore the floor pan work). People will sometimes weld in a piece of sheet metal in the opening.

Thank you. Yes they welded a sheetmetal piece. What is the benefit of welding it shut? Road noise? Structural support? Curious because this is going to be a track car with 600hp.

I'll post pics soon.

 

[jws66m]

Picture of yours would help

I'll post pics soon. Someone welded sheetmetal over it.

 

[wicked93gs]

Thank you. Yes they welded a sheetmetal piece. What is the benefit of welding it shut? Road noise? Structural support? Curious because this is going to be a track car with 600hp.

I'll post pics soon.

A heavier gauge piece(14 gauge) will add a decent amount of torsional rigidity, even a lighter gauge piece might add some. Some people put them in thinking that it would help prevent fuel from sloshing into the passenger compartmentin the event of a rear end collision(I don't see that happening myself)

 

[Flade]

Testing a number of years back showed that the Mustang flexes in that area and bracing it significantly helps. In the Cougar, Mercury welded diagonal braces there supposedly for that reason. Just adding a large metal plate will act like a drum and is not super rigid. It needs beads rolled into it or a bar welded across it to reduce flex and oil canning. Then add butyl sound deadener.

 

[jws66m]

I'll post pics soon. Someone welded sheetmetal over it.

Here's what's in there. Its just thick and flat so it doesn't offer anything of real value. Plus a roll cage is going in.

I'll post pics soon. Someone welded sheetmetal over it.

 

[wicked93gs]

A roll cage is the best as far as torsional rigidity goes....but that most certainly does offer some. If its a race car I would leave it and cut holes for the cage tubing.

 

[dennis111]

If you are building a race car, you may want to leave the panel as-is for a partial firewall from the fuel tank (NHRA sometimes require one.) It would have been better if it had some bead rolls as it will make noise without some support.

You could leave it and have the cage tubes bent to go down through the speaker hole area, as I did.

Here is how I handled my 65' roll bar installation before I added the rear firewall:

If you're bored, here is a thread (from start to finish) on my roll bar installation: 11.50's no more--Legally! | Ford Muscle Cars Tech Forum (fordmuscleforums.com)

Here is the bead rolled firewall that I made/installed:

Rolling the bead took care of the "tin can effect" noise.

 

[jws66m]

If you are building a race car, you may want to leave the panel as-is for a partial firewall from the fuel tank (NHRA sometimes require one.) It would have been better if it had some bead rolls as it will make noise without some support.

You could leave it and have the cage tubes bent to go down through the speaker hole area, as I did.

Here is how I handled my 65' roll bar installation before I added the rear firewall:

View attachment 871588

If you're bored, here is a thread (from start to finish) on my roll bar installation: 11.50's no more--Legally! | Ford Muscle Cars Tech Forum (fordmuscleforums.com)

Here is the bead rolled firewall that I made/installed:

Rolling the bead took care of the "tin can effect" noise.

It needs to go and be replaced. I have a cnc guy that can cut any shape and then I'll have a body shop put beads in it. It does rattle and can be thinner.

Yours looks good. I'll save it as a reference.

 

[wicked93gs]

It needs to go and be replaced. I have a cnc guy that can cut any shape and then I'll have a body shop put beads in it. It does rattle and can be thinner.

Yours looks good. I'll save it as a reference.

If you are going thinner, don't bother to put it back in in, it needs to be at least 16 gauge to be any use strength-wise. I myself just decided to put cross bracing in...like just about every coupe of any model without fold down rear seats from '69+ had:

 

[jws66m]

If you are going thinner, don't bother to put it back in in, it needs to be at least 16 gauge to be any use strength-wise. I myself just decided to put cross bracing in...like just about every coupe of any model without fold down rear seats from '69+ had:

Looks good. Are those braces from a specific kit or something you fabbed?

 

[wicked93gs]

Looks good. Are those braces from a specific kit or something you fabbed?

I took them from a Mazda RX-8(they bolt into that car), cut them slightly, then welded them in. They are nice, multi-layered shaped metal that weigh very little.