Let's talk about subframe connectors. EDIT: Got one in.

[Adam]

I know this topic has been beaten to death. I've seen lots of good ideas on subframe connectors. My car is (was?) very rusty, especially in the floors, rear wheel wells, trunk floor, tail panel, rear bumper crossmember, front frame rails, inner fenders, etc. I know some of these components are not especially structural, but I also had collision damage on the left rocker and I replaced the inner, and outer rocker skin. I made the inner out of 16 gauge so I shouldn't have a problem there.

Either way, I will be doing the floors soon and want to decide first what I am going to do with frame connectors. I already have two, 2x3x1/8 tubes about 60" long that I will use to make them.

Those of you who put your connectors in vertically (as in, 3 inches up and down) and inside the rear frame rail, this is what I would like to do as I can tie it into the floor more easily. I have a few concerns, however. The inside width of the rear frame rail is larger than 2 inches. What did you do for a tight fit? Also, with the frame connector sticking up through the rear floor pan 2+ inches, what do you plan to do for a carpet?

I am thinking of trimming down the frame connector so it doesn't come through the rear floor, but then I'll only have ~1 inch height-wise of frame connector for the rear floor pan. What do you guys think?

This is a 76 Dart sport, will have a 72 Duster front clip, and I will be using a 383 (plans are for 400-450 horse), a 4-speed, and a 3.91 Sure-Grip 8 3/4 with probably 275/60R15 tires, maybe a bit bigger. I'm just concerned with it flexing. It will be a street/strip car, mostly street, with a few trips to the track every summer. I plan on driving it pretty much daily, not beating it too hard on the street but it will see its share of "spirited" launches and I want the car to last. I will be keeping the rear seat and it will see use by passengers, so foot room is an issue too.

So, enough about my car. Show me what you've done with your connectors, and any pros and cons with them.

[abqdart]

If I run in to that issue I will  use 3/16 plate on both sides if the 2 x 3 and then weld the frame rails to it. I plan on drilling 1" holes in the sides and bottom to rosset weld.

[redfastback]

on my 68 cuda, i used the magnum force tubular subframe connectors.  they have a flat plate on the tranny end and the other end slips over the frame rail.  my buddy tig welded them into place for me.  they made a HUGE improvement in how much the body did NOT flex.  i am running about a 400 hp sb 360.  any frame connectors you choose will help out.  the 2x3 should blend in with the frame rails.  here is a couple of shots of them.

[farmington]

I used 2x2 tubing in my duster and the connectors only come through the floor about 1/2".  With the carpet down you don't even know they're there.  How much do you plan to use the rear seat area anyway?

[Adam]

Thanks for the responses, guys!

I like the idea of running a plate to take up the slack in the rails. I will probably take that route, and trim the 2x3 down to 2" maybe where it goes through the rear floor. I don't care if it sticks up a little bit, I just don't want to have it stick up 2 inches and affect the fit of the carpet.

The car will be my daily driver in the summertime, and it's not uncommon to have all 5 seats in my current driver filled.

The only thing I don't like about those tubular ones is that it would be hard to weld them to the full length of the floor. I tend to go overboard when it comes to stuff like this....and with the street driven big block 4-speed before, I had issues of paint cracking at the rocker/quarter joint from body flex. I will be getting a killer paint job this time around and would like to avoid this again.

Another reason I want to put the 2x3 tube vertically, is because I will be able to run it inside the rear frame rails for probably 8-12 inches. It can't be too strong, right?



Adam

[mopowers]

I am thinking of trimming down the frame connector so it doesn't come through the rear floor, but then I'll only have ~1 inch height-wise of frame connector for the rear floor pan. What do you guys think?

In my opinion, if you're going to cut the tops off, you might as well lay the 2x3 flat. 

I did my subframe connectors this way (verticle).  All I did for the rear portion was make another peice to cap the rear frame and weld the two together.  Here are some pics of how I did it.  Just remember, there's more the one way to skin a cat.











As for carpet, I was just going to lay it over and not worry about it being a perfect fit.  I wont have a back seat, I'm not too concerned about it.

[79ramcharger]

Mopowers How much does that stick thru the floor boards?

Thanks,
Steve

[Adam]

Thanks for the pics Mopowers.

I wil probably run them vertically, with a plate on either side of the steel, and trim the tube from 3" to probably 2" and re-box it but only where it goes through the rear floor. I want to tie it into as much of the floor as possible. That way I can even go so far as to run my seat mount reinforcements from the inner rocker to the subframe connector, etc....We'll see how I decide to do it when I actually do it. I might make my own rear floor pans too as opposed to buying them, so I suppose I could just make them sit on top of the 3" tube, and then trim the carpet accordingly. I am also not worried about perfect fit but I want it to look good, and still be functional.

Thanks for the opinions, guys.

Adam

[mopowers]

Mopowers How much does that stick thru the floor boards?

Thanks,
Steve

The car is at my folks house, but I think it's about 1.5" or so.

[79ramcharger]

Hmm I will have to cut a 2x4 so I can see what that is going to do to the carpet. Another question. I'm planning on moving my springs in like in the tech section. I'm thinking of combining the frame connectors and the front spring mount. In the tech section they did it in 2 steps first the spring mounts then the frame connectors. Seems to me a person could use one piece of steel and do both at once. Thoughts??

Steve

[Adam]

Steve, I don't see why you couldn't do it that way.

Are you talking about making your own spring relocation 'box' and having it be part of the frame connector? Or buying the kit and simply putting it in at the same time?

If it was me, I would probably do it in two steps just so I don't cut out too much frame/floor/whatever all at once. Call me paranoid but I don't think it would take much for one of these cars to twist up real good once you cut too much out (which is why I've been measuring the living crap out of everything to make sure it's still straight).

Anyways, a small update. I was going to put the left side frame connector in last night, but I found a pencil eraser sized hole about 2 inches from the torsion bar mount in the transmission crossmember. Upon grinding around it I found about a dozen more holes. So, I decided to patch it and reinforce it. Here are some updated pictures. Connector will go in tomorrow provided I'm not too lazy to go out and work on the car, like I was today.





After grinding



After patching. This patch that I made goes on the back of the trans crossmember (shown) and also bends around onto the bottom. I will reinforce the front at a later time when I have the torsion bar out too. I will probably do the other side too, while I have the car apart, just to be safe.

Chugging along with metal work,

Adam

[Adam]

Got the driver side connector in today.



Sickening the amount of smoke that builds up inside the car. Literally. Talk about a labor of love 







That's all for now. Probably tomorrow I will get started on the floor pan under the rear seat area.

[mopowers]

Looking good Adam!!  Keep up the good work and she'll be on the road in no time!!

[Adam]

Thanks for the kind words Mopowers.

I plan on finishing up the frame, floors, trunk floor, and subframe connectors, doing a brake job (including lines), rebuilding the engine and trans, and fixing any wiring flaws, and repainting under the hood, and driving it this year with a blue fender on one side, grey on the other and a white hood. Then doing an actual body/paint job next winter. We'll see how it goes.

I drove it from a local body shop (less than 2 miles) from my buddy's house to where I am working on it now with no insurance, no plates, no grille, lights, or bumper on the front, no interior less one seat, and glasspacks hanging off the headers to keep the noise down a bit. This was just before winter and it was the first time I had driven it since winter 2005. It's been close to three years since this thing has been legitimately on the road and I miss it dearly. Hell gas was downright affordable back then.


Adam

[75Dart440]

I used 2x2 tubing in my duster and the connectors only come through the floor about 1/2".  With the carpet down you don't even know they're there.  How much do you plan to use the rear seat area anyway?

I used 2 x 2 on my Dart Sport and didn't have to get into the floor pan.  Driver's side connector just barely touches the bottom of the rear pan foot well at one of the ribs.

[doug 371]

on my 68 cuda, i used the magnum force tubular subframe connectors.  they have a flat plate on the tranny end and the other end slips over the frame rail.  my buddy tig welded them into place for me.  they made a HUGE improvement in how much the body did NOT flex.  i am running about a 400 hp sb 360.  any frame connectors you choose will help out.  the 2x3 should blend in with the frame rails.  here is a couple of shots of them.

tinfoil for masking...now there's a great idea i never thought of...

[Scamp 408]

Good deal Adam .Whats the width of the open part of the rear fram rail?

[Adam]

I'll have to measure to verify but I seem to recall it being around 2 3/4 or so at the top of the frame rail. I'm pretty sure it widens a bit at the top. I will check for you tomorrow when I'm working on the car.

Adam

[redfastback]

on my 68 cuda, i used the magnum force tubular subframe connectors.  they have a flat plate on the tranny end and the other end slips over the frame rail.  my buddy tig welded them into place for me.  they made a HUGE improvement in how much the body did NOT flex.  i am running about a 400 hp sb 360.  any frame connectors you choose will help out.  the 2x3 should blend in with the frame rails.  here is a couple of shots of them.

tinfoil for masking...now there's a great idea i never thought of...

when i learned about it, i was amazed at how easy and fast you can mask something as well as removing it.  fantastic for odd shaped things.

[BIG DOG]

Mine are 3X3 tied into the rear relocation boxes on the rear with out riggers and seat brackets to the sills.I think it looks great and doesn't interfere with back seat room too much at all.

[abqdart]

VEry nice!

[redfastback]

now that is what i'm talking about!  looks great!

[Adam]

Dude that is a killer floor/frame connector/seat mount job. Mine won't be half that nice when I'm done

Did you cut out the entire floor and weld it back in, or is that floor from another car?

Scamp 408, the inside width of the frame rail was about 2 3/4 at the bottom where it is only an inch tall or so (right at the front under the rear passengers' foot area) and was about 3 1/8" at the top right under the seat near the spring mount. I'll post a picture later if that doesn't make sense.

Adam

[Scamp 408]

Thanks Adam I just got done with the roll bar now I am going to redo the frame conn. Yours look good keep it going.

[BIG DOG]

Dude that is a killer floor/frame connector/seat mount job. Mine won't be half that nice when I'm done

Did you cut out the entire floor and weld it back in, or is that floor from another car?

Adam you will be surprised at how well it will look.You look like you have a pretty good handle on it ! Keep the pics coming and don't get dicouraged I find that's the hardest part about my project.
The floor was drilled out at the spot welds. I bought 1 floor pan  hand made 3 floor sections then used part of the original floor and part of a donar car.I keep telling those guys from the states that they don't know how good they got it!!

[dangerdawg]

makes me wish i'd done my own. very good work, be proud.

[moparchop]

Hope you guys dont mind me butting in ,I already put my floors and trunk in,great.I have been away from building for sometime,and it looks like I made my first mistake,great...I guess they make 2 by 2 connectors,dont they?