Tremec 5 speed swap into a '70 Charger

[OzCharger69]

Thanks so much for this Kern Dog. I am glued to this thread. I will be doing this swap at some stage.

[Kern Dog]

I'm glad to help, guys. I enjoy passing along whatever information that I can. 

[Kern Dog]

I mentioned awhile back that when I had the Gear Vendors unit, I didn't have to clearance the trans tunnel like everyone said I would. I had at least 1/2" of clearance between the tunnel and the GV unit. I had a modified trans crossmember in the car and suspected that it may have the trans mount too low.
Today I confirmed it. I actually stumbled across this determination....Funny how that happens. I had the hood up on Jigsaw and was looking at the transmission crossmember that was just loosely mounted in the chassis.
See the pictures.
The first ones are the freshly painted stock crossmember with a NEW mount. Notice the height of it, how it sits above the holes that mount the crossmember to the car.

[Kern Dog]

Here is the crossmember that has been in the car for almost 9 years. Notice how low the mount is!

[Kern Dog]

Yeah....that is 1 3/8" lower than stock.
Even with the 1/4" shim I had in there, the trans still sat 1 1/8" low. I never had bad vibrations, never wore out a U-Joint either.
Before I took the 727 out, I measured the distance from the floor to the top of the header collectors. It was hard to get a direct sightline but it looked to be between
2 1/4 to 2 1/2".

[Kern Dog]

Carpet is out.
Looking at all this sound deadener, it is no wonder this car is 4000 lbs!

[Kern Dog]

I took measurements of where the automatic trans shifter bracket sits before removal. This will help when I convert Jigsaw to a floor shift setup.

I first planned on using the 4 1/2" angle grinder to cut the welds but the blade wasn't big enough to reach. I ended up using a Sawzall. That was a better idea anyway since it cut down on shooting sparks.

First though, I had to peel up some of this sound deadener. I marked a perimeter then cut through to the metal with a utility knife. I used a screwdriver to lift an edge, then pulled it up. It came up a whole lot easier than I expected.

[Kern Dog]

Silver Sport provides a paper template to determine where to cut the tunnel. The top side of the Tremec sits higher than any 727 so the floor has to be opened up to make room.
I used a pair of 16 penny nails to properly position the template, then taped it down and cut 1/4" inside of the lines. I figured that it is easier to cut more later rather than to add metal back.

[Kern Dog]

I used the transmission jack to lift the Tremec into place. The front bearing collar was spritzed with a little WD40 to help it slide into place. There is no clutch or pilot bearing in place, this is just a test fit to see if the tunnel hole is big enough.

[Kern Dog]

It fits!

The instructions and paper template were excellent. I did need to pry a bit to get some  tunnel clearance on the right side. The left side is real close but I'll just bend the edge rather than to cut out more. The rear edge is about 3/8" to 1/2" from the torsion bar crossmember. I'm going to cut it out to the crossmember though. This will help the shifter stub clear the opening when I install the trans for good. With the trans in place, the header collector now sits 1 7/8" from the floor. That means that the transmission raised up between 3/8" to 5/8". This will give a bit more ground clearance for the headers.

I have several things waiting to arrive. I bought new carpet from Rock Auto. I've learned that almost ALL classic car carpets are made by ACC. Yeah...There is no reason to pay more so I bought from them. This kit comes with what they call "Mass Backing", some type of padding that is supposed to reduce heat and noise. It may be overkill since I have all that sound deadener.
I ordered offset dowel pins, they might be here as soon as Friday. Once those are installed, I can mount the flywheel, pilot bearing, clutch and pressure plate.

[XH29N0G]

Kerndog,

What I suggest may not be pertinent because I have an older model with a different front top.  They probably have it sorted, but I would do a quick check to see if you can estimate what your driveline angles are likely to be.  

What I found was that I had to massage the front of the tunnel to get the angles right.  There could be another cause (I wonder like old springs in the back, different engine position, shimmed K-frame..... but it might be worth a check (even a mock up) while the car is in this state.  

[Kern Dog]

There is plenty of clearance there in this car. Maybe the mods that Silver Sport does alleviated the fitment issues that others have had before?

The RobbMC Performance .014 offset dowels came in today. The trans is still in the car though and I wanted to work on the sheet metal tunnel patch.

First up, I reshaped the opening a little. The left side was bent outward a bit instead of being cut more. The rear edge was cut back to the edge of the torsion bar crossmember. This will help with removal and installation since the shifter sits on that blocky stub and it makes it tough to fit into place.

[Kern Dog]

The SST kit came with the sheet metal section to patch over the hole. There were no instructions on how to shape it or anything, just a picture. To be fair, they sent me a 4 speed to 5 speed set of instructions instead of Automatic to 5 speed.
Not a problem for me though. I took a sheet of cardboard as a template.

The dent in the sheet metal was in it when I got it. No problem....The whole she-bang hides under the console.

[Kern Dog]

I attached it to the tunnel with screws. It will come back off so I can clean the paint off to get good welds.
I'll lift the car up and see how it looks from underneath soon.

[Kern Dog]

I was concerned that the patch might interfere with the console. It all clears just fine though.

[Kern Dog]

I did encounter a problem though.
Before I even started this project, I planned on taking the console top plates from this car and use them on Jigsaw. For Ginger here, I wanted to dechrome the pieces and paint them a Satin Black. I searched for and bought a set of console parts from a guy on FBBO. A guy at the 1970Charger Registry said that he modified an Automatic transmission top plate to use with a 4 speed so I figured I was all set.

I took the one I bought and sandblasted it. Today I cut the divider from the middle.  Here is the console in the stock position:

[Kern Dog]

The transmission is in neutral. There is no way that this will work.
I was wondering if I could move the console forward to center the shifter in the opening but that means building a new bracket to support the rear of the console.
I could find a way to move the shifter rearward by welding an extension on the adapter bracket.
I asked around and learned why the shifter sits so far forward and why the Automatic trans version is so far off...
Here is MY plate:

[Kern Dog]

This is a stock 4 speed top plate.

[Kern Dog]

Yeah...The automatic version hole is from 11 3/8"  to 15 7/8"  and the 4 speed one is 8 3/8 to 14 1/2".  I don't know how the other guy made his work without adding to the end nearest the console door. Now I'm on the lookout for a used 4 speed plate.

[Kern Dog]

I lifted the car up so I could measure for the drive shaft. For years, everyone I have dealt with says to measure for the shaft with the car resting on it's own weight. I measured the distance with the tires hanging, then put the car on screw jacks with the car barely off of the lift pads...

The drive shaft was 58 9/16" at full droop. Care to guess the difference with the car on the jacks?

[Kern Dog]

It was the SAME!
Crazy, huh? It didn't change but maybe 1/32 of an inch. SST was clear about measuring the "right way". Everyone is.
Maybe mine didn't change because I have less suspension travel? I have MP 440/Hemi springs and a rear sway bar. The bar does limit downward axle travel a bit but this was an interesting discovery.

[darbgnik]

It was the SAME!
Crazy, huh? It didn't change but maybe 1/32 of an inch. SST was clear about measuring the "right way". Everyone is.
Maybe mine didn't change because I have less suspension travel? I have MP 440/Hemi springs and a rear sway bar. The bar does limit downward axle travel a bit but this was an interesting discovery.

I was surprised by that, myself. 

[TexasStroker]

Nice progress!  Hopefully you can find a 4 speed top plate to swap.  It would be a lot of work, but you could cut out the center section and insert your material of choice.

[OzCharger69]

Wonderful progress mate.

So you kept the Auto console and just planning to change the top plate. Hopefully they are interchangeable.

I know the manual console has a bigger bump on the driver's side to accomodate the side linkage of the 4 speed.

https://www.ebay.com/itm/PG-Classic-131-70-Mopar-1969-1970-B-body-Woodgrain-4-Speed-Console-Top-Plate/372649849288?fits=Year%3A1969%7CModel%3ACharger&epid=2143165749&hash=item56c3a971c8:g:hTwAAOxy1RZSaU4m

[INTMD8]

It was the SAME!

Still good advice to check it with chassis loaded for most, as most don't understand the reason for variance.

At full droop with long shocks the front half of the leaf pivots the rearend towards the front of the car. (after dropping below or above parallel arc travel moves centerline forward)  If you have limited travel in the extended range and start out with the spring -flatter- and stiffer so it ends up flat, you have little fore/aft movement.

But, take a guy with old soggy springs, shackles at full droop, vs sitting on the ground, could be a substantial difference.