'69 Barracuda T56 swap, floor, cross member

[340sFastback]

Haven't done anything major to my car for 12 years. So after pondering a manual trans swap for the last several years finally made the decision to go T56 Magnum. But to do the transmission swap I had to address some floor rust which has been there since the '80s. Back then I fixed all the water leaks and slapped some fiberglass on the rust holes in the floors and it stayed like that until now. Also had one small rust hole in torsion bar cross member so instead of patching decided to replace. Been at it a few weeks now so lets dive in.

Here is the car the last drive with the 727 automatic. Did one last big smoky burn out with the automatic trans and stroker engine combo. After this picture car was pulled in garage and taken apart.

 

[340sFastback]

First order of business was to pull the engine and trans. Trans has been sold to a member on this forum in Long Island NY so it lives on in another car.

 

[340sFastback]

Next get seats carpet out and take a look at floor rust that has not been seen in 40 years. Been so long wasn't really sure what was there cause from bottom of car a bunch of under coating spray bombed covered up the mess from below. Luckily I did a super half assed fiber glass patch and was able to easily pull them off the floor. Red primer area passenger's side rear foot well is a snow shovel buried in caulk to patch a big hole back there cause by a spot weld hole in rear wheel well allowed water to fill that area up. But hey I did stop all the water leaks decades ago kept it from being worse.

 

[340sFastback]

I asked @72bluNblu for advice and he told me leave as much floor in as possible when removing the torsions bar cross member. So I braced up car and removed the section of floor above cross member. I adjusted the RV Jackstands made sure both doors open closed and body gaps looked good. The jack stands at the very front I ended up removing because body really hated any support applied there. Torsion bars are removed so the front tires help stabilize car and carry rotor/hub/spindle/tire/wheel weight. The less weight pulling on the body structure the better.

 

[340sFastback]

Next was to remove old torsions bar cross member and clean up the front frame rails. I used a 4' long angle iron as a straight edge to lay across frame rails to straighten mounting flanges on the front frame rails.

 

[340sFastback]

Next was to get the AMD cross member to fit.

NOTE Torsion Bars must be in place to insure alignment of cross member. There is no forgiveness with torsion bars if cross member angle is off even a hair then torsion bars won't go in.

The cross member mount tabs where it meets inner rocker panel required extensive bending, shaping, forming in order to get them to lay flush against inner rocker. I taped card board to cross member to mark where inner rocker was located, removed cross member, bend tabs, and repeat over a few days time frame until I got a nice snug fit. I search and others replaced their cross member but no one said anything about having to monkey around with those mount tabs to get a good fit. So don't know but I was not going to settle for some sloppy fitting frame structure.

 

[340sFastback]

Welded in cross member, cut out center section, and test fit the ToddRon T56 center section. The bolt holes for the ToddRon cross member were drilled into the cross member prior to cross member install.

NOTE: torsion bars are installed, and I constantly checked while welding to insure they slid in and out easily no drag indicating cross member alignment was correct.

 

[340sFastback]

Welded in the ToddRodd center section. Afterwards torsion bars, which still slid in/out freely, were finally removed. Car is still on all the jackstands and doors open/close nicely and body gaps still look good.

 

[340sFastback]

Shortly after I bought car in 1979 I broke a motor mount. I jacked car up with a bottle jack and crushed driver side front frame rail. I was able to insert 1/4 thick 2x4 steel into top of frame rail, squeeze frame rail with C Clamp, work side dent in first, then hammer frame rail back into its non-crushed shape. I didn't use any heat. Very happy to finally get rid of that frame dent after so many decades. I always hated seeing that crushed rail every time under the car.

 

[340sFastback]

I ordered a T56 Magnum swap kit from Silver Sport which came with pedals, transmission, clutch ect. Reproduction console shifter handle and console top plates from Brewers. Will have to cut base and weld to adapt shifter handle to mount to the 6 spd. Going for a factory 4 spd look.

The mocked up console display keeps me motivated while I am deep into cutting/welding/fabricating ect. Not to mention the car will be off the road the entire car show season this year cause I plan to drag *** take my time not rush aiming for some quality work.

 

[340sFastback]

Before cutting out rest of floor decided to test fit console with original console brackets still in place. Once new floor is in I will take this test fit into consideration when I custom fab the larger trans tunnel.

 

[340sFastback]

Prior to welding in cross member I laided it up to floor and cut floor hoping to clear T56 center section once floor is set into car.

 

[junkyardhero]

awesome work! i'll all be worth it at the end! i love the idea of the factory console shifter set up hiding the 6spd. that's excellent.

your car and mine are shockingly similar-- both dark green, black steelies, dog dish caps-- i had a momentary double take!

 

[A56]

Awesome work and documentation. The replacement of my own torsion bar crossmember and floor pan is coming soon. I plan on installing the USCT inner rocker panel supports since my rocker panels will be opened up.

 

[340sFastback]

Top flange passenger's side front rail was rusted. Cut out, fabbed a 14 gauge steel patch, butt welded in.

 

[340sFastback]

Passenger's side front the brace that ties floor, frame rail, rocker together had a rust hole. Cut out and butt welded in an 18 gauge patch. Welded from both sides to restore the strength. Luckily no rust exist on firewall.

 

[340sFastback]

Brace on driver's side was bent up and torn from lifting car with bottle jack back in 1979 which also crushed the frame rail. Now that rail was bent back into shape I was able to straighten brace and weld back together. Welded from both sides to restore strength.

 

[340sFastback]

Cross member replacement and front rail repairs are completed at this point. No more rot, no more crushed frame rail, no more torn metal ect. Next is to remove rest of floor rear of the cross member and work on some repairs toward rear. I will be coming back to hammer dolly and clean up firewall flange later.

 

[340sFastback]

Removed the rest of the floor. No rust holes on inner rocker they are very solid so that was good to see.

 

[340sFastback]

Both corners of that over-the-axle pan are rusted where it meets the main floor. Small arear above driver's side frame rail rotted out. Will need to cut back to clean metal, fab up some 18 gauge patches, butt weld in new metal.

 

[340sFastback]

Fabbed up and butt welded in patch on driver's side rear corner. Also welded up some small rust holes pin holes over there where I could grind/flatten both sides of the panel. Welded up two slices in the inner rocker when floor was cut out. Wire wheeled cleaned up of that entire corner area. Took way longer then expected. Working on passenger's corner now.

Don't really know why that half-circle is in that panel? But thats how it was so wanted to retain that look.

 

[moparlvr166]

Brace on driver's side was bent up and torn from lifting car with bottle jack back in 1979 which also crushed the frame rail. Now that rail was bent back into shape I was able to straighten brace and weld back together. Welded from both sides to restore strength.

View attachment 1716078718

View attachment 1716078719

View attachment 1716078720

Nice to be able to fix things from learning when younger and the best part it's with the same car, not many of us have the same cars from our youth. Nice work and upgrades.

 

[mygasser]

when welding pin holes if access is too tight to grind the backside hold a lump of copper behind the hole as you weld it. it stops the weld going through so it stays flat and copper won't stick to the weld.
neil.

 

[rich_mc]

Did you also consider Silver Sport's TKX kit? What made you decide on the Magnum? Potentially considering this project for next winter.

 

[340sFastback]

Did you also consider Silver Sport's TKX kit? What made you decide on the Magnum? Potentially considering this project for next winter.

Thought about a TKX yes and it is a good option - it is a tad smaller, lighter, and a bit cheaper then 6 spd. But I liked the ratios of the 6 spd better and wanted the two over drive gears. T56 Magnum has an outstanding reputation and is known for its shift quality and durability. But I have seen youtube reviews of TKX and people really like how it shifts once they get it installed.

So it boils down to personal preference TKX or T56 Magnum. I would look at gear ratio options between the two, consider size and weight differences, look at price differences, consider which would work best for your car and how you plan to use it ect and decide.