confusion on frame connectors

[beanhead]

Regardless of which direction you choose for your SFC's, they need to be welded in while the car is on its wheels. If you put it on a two post lift, jack stands, jacks etc, the body sags from the weight. Once welded in place, have fun opening or closing the doors. If you have an empty shell with no drivetrain, interior, glass etc, then it generally is not an issue to put them in while on a two post lift, rotisserie, stands etc.

Agreed!
My buddy made some cradles that you put under the tires once the car is jacked up, they probably raise the car oohhh about 2 feet...not as nice as a lift of course but the car "thinks" it's sitting on it's wheels.

 

[eldubb440]

I only weld them with doors installed and aligned ....... with some wiggle room, not maxed out on the adjustment

 

[Kern Dog]

Those that have actually been under one of these cars must have noticed the way the factory patched together the unibody. The front frame rails are pretty thin but when spot welded as they are, they form a box. The manner of attachment of the front rails to the torsion bar crossmember is not that robust though. I’m talking simple tabs spot welded to another member? No full welds, lots of open spaces too. Somehow, it worked.
I was trained to build things to withstand earthquakes. The 1989 San Francisco event dramatically changed building standards and I was there to see it. I’ve grown accustomed to thinking that everything has to be built to that standard. My own house was built before that and has none of the radical bracing, gussets, brackets or straps yet…it still stands.
Knowing that, I’ve begun to question the value of some of the stuff we do to the cars.
I love big brakes and better handling so stuff like chassis stiffening will remain important to me.

 

[eldubb440]

Those that have actually been under one of these cars must have noticed the way the factory patched together the unibody. The front frame rails are pretty thin but when spot welded as they are, they form a box. The manner of attachment of the front rails to the torsion bar crossmember is not that robust though. I’m talking simple tabs spot welded to another member? No full welds, lots of open spaces too. Somehow, it worked.
I was trained to build things to withstand earthquakes. The 1989 San Francisco event dramatically changed building standards and I was there to see it. I’ve grown accustomed to thinking that everything has to be built to that standard. My own house was built before that and has none of the radical bracing, gussets, brackets or straps yet…it still stands.
Knowing that, I’ve begun to question the value of some of the stuff we do to the cars.
I love big brakes and better handling so stuff like chassis stiffening will remain important to me.

they were all cheap cars, in competition with other cheap cars........ there is lots of room for improvement

that being said, unibody structures haven't changed much......it's a pretty sturdy design

 

[matthon]

Also, if a 3 sided one were welded to the floor, it would mimic the factory frame rails since they were U Channel of 14 gauge steel relying on the thin 18 gauge sheet metal floor pan. That is assuming you could weld an inside corner with the same solid connection as the factory spot welds from a flat flange on a frame rails since to the floor pan.

This. Connectors are different gauge than the floor, an inside corner weld, and a pain in the rear to weld all those contours.
They look great once installed, to no one.

Square tubing without cutting into the floor would be my vote.

 

[Kern Dog]

This plays to my point about diminishing returns. What gains are there from welding to the floor?
The pre cut floor fit types are more expensive than buying 8 feet of 3x3 .090 wall tubing from your local metal supply yard.

 

[eldubb440]

This plays to my point about diminishing returns. What gains are there from welding to the floor?
The pre cut floor fit types are more expensive than buying 8 feet of 3x3 090 wall tubing from your local metal supply yard.

I'd say the connector welded to the floor plays a major part.......I think it also limits any "twisting"

you know plywood keeps a wall racked, I'd say it also eliminates or greatly reduces the twist

 

[Kern Dog]

I'd say the connector welded to the floor plays a major part.......I think it also limits any "twisting"

I think there is merit to this but how far would one need to push their car to know?
I have pushed my car pretty hard on the street. Where my connectors meet the floor, I just spread seam sealer to fill the gaps. I scuffed, primed and painted the floor afterward. This was 2012. I have seen no separation between any of it.

Maybe I need to push the car harder?
I do corner it harder than anything else I drive.

 

[eldubb440]

I think there is merit to this but how far would one need to push their car to know?
I have pushed my car pretty hard on the street. Where my connectors meet the floor, I just spread seam sealer to fill the gaps. I scuffed, primed and painted the floor afterward. This was 2012. I have seen no separation between any of it.
Maybe I need to push the car harder?
I do corner it harder than anything else I drive.

all I know is I welded the **** out of that convertible..... on the rotisserie or on the tires, ZERO change.....it's a stiff bitch, without a roof

 

[Dennis H]

Compelled to story time, sorry. My welder (Joe Sanderson RIP) ended up in the ER due to inadequate PPE when grinding off the undercoating in the summer heat. Helluva rash.

They look factory to an untrained eye. First ride on a washboard street had less rattles, more like a modern car. Doors noticeably better operation.

Prior to installation, had the 440 warmed up by Mopar Engines West. 415 RWHP Chassis. Cracked the windshield after first romp. Subsequent romps after Connectors have not cracked the windshield.