Out with the Automatic and in with the Tremec 5 speed

hemi446 · Feb 4, 2018

I have had this Tremec 5 speed for a couple of years. I bought from a friend of mine father -in- law it was in his 73 Hemi Challenger and he decided to switch to an automatic it has about 1500 miles on it. I did have to get a new extension housing and shifter for it from American Powertrain along with there transmission tunnel sheet metal, speedo cable and cross member.
So after some friends of mine started bugging me to go to the 50th anniversary of the 68 Super Stock Barracudas and Darts and get off my *** and put the Tremec in. I decided if I didn’t get started on it now it would never get done. So today I started taking apart a good running car getting ready to cut up my perfectly good floors. The plan was to take the interior out and install the pedals, so I can take it to my shop and pull the transmission and start cutting the floor out.
I looked around to see if I could find anyone the used the American Powertrain cross member and sheet metal with pictures, but no luck so I plan on taking pictures along the way so someone else could have an idea of whats involved.

dano · Feb 4, 2018

Bust of luck. I was working on fitting a console to my TKO swap. The front of the console needs shaved down to get it back to the stock location and in my case the shifter was moved forward about 1" to 1-1/4" -vs- the stock location and moved towards the passenger side, so the console is moved forward too. Your new tunnel will be taller and wider. My stock 4 speed drive shaft was the correct length for the TKO so measure yours first. I have the Hurst Conversions kit, might consider their stuff too, they were great to work with.

hemi446 · Feb 4, 2018

I need to make sure the brackets will work with the console I’m going to try and make the tunnel fit as tight to the transmission as I can. I want to keep the console and modify the factory shift handle so it will fit. I’ll just keep taking pictures so if you have any other advice I’m happy to listen.

darndart · Feb 4, 2018

Subscribed. I was planning on doing the same to my 72 Duster. I already have a new Tremec, Quick Time bellhousing & American Powertrain hydraulic clutch kit. Keep the pics coming!

BrianT · Feb 5, 2018

Same here. I'll be following along with ya!

coalman · Feb 5, 2018

I hope everything goes well, I got a quote from Silver Sport for the complete set up awhile back, just too much$$$$$$.

dano · Feb 5, 2018

coalman said:
I hope everything goes well, I got a quote from Silver Sport for the complete set up awhile back, just too much$$$$$$.

Yes. They quoted me as well. Hurst was the best and American Power train doesn't include a Bell.

coalman · Feb 5, 2018

dano said:
Yes. They quoted me as well. Hurst was the best and American Power train doesn't include a Bell.

I don't think Hurst has a setup for early "A" Bodies....

dano · Feb 5, 2018

coalman said:
I don't think Hurst has a setup for early "A" Bodies....

Is that an issue or difference over 67-up? Either way your cutting the floor board if its not a Silver State kit. I don't trust the machining done by Silver State to have not compromised the strength and seal any leaks.

FYI for all, Hurst kit install.

HURST DRIVELINE CONVERSIONS Mopar 1967-76 A-Body » HURST DRIVELINE CONVERSIONS

coalman · Feb 6, 2018

dano said:
Is that an issue or difference over 67-up? Either way your cutting the floor board if its not a Silver State kit. I don't trust the machining done by Silver State to have not compromised the strength and seal any leaks.

FYI for all, Hurst kit install.

HURST DRIVELINE CONVERSIONS Mopar 1967-76 A-Body » HURST DRIVELINE CONVERSIONS

When, I was looking, Hurst did not advertise anything older than 1967, Silver Sport did. It doesn't matter, it is just too expensive in my situation... Thanks

hemi446 · Feb 7, 2018

So I got the new bracket and pedals back in the car late last night. I hoping the weather isn't to bad one day this week so I can drive over to my shop and pull the automatic out along with the trans cooler and the shifter assembly this weekend and start mocking up the bell housing and transmission so I can cut the floor and the torsion bar cross member. Since my Ram clutch set up and flywheel didn't come with a clutch alignment tool and Ram wants you to buy one for 49.99 for this real nice shinny steel tool that I will use once. I looked for the cheap *** plastic one from Dorman but the Tremec uses a 1 1/8" x 26 spline Ford input shaft. All they have is the Chevy alignment tool and it's way different than the Ford input shaft even thought they are suppost to be the same. I'll have to do something different when it come time to install the clutch assembly. For now I just need to mock up the clutch and transmision on an old block I had sitting around to get the measurements for the hydraulic release bearing setup and to make sure it still works since it's been sitting for awhile.

hemi446 · Feb 7, 2018

Today work was slow so I decided before I go to class tonight I would test fit transmission clutch and bellhousing together so I can hook up the master and slave cylinder to make sure everything is working like it should
I did have to remove one of the shims between the release bearing and transmission to get the clearance they call for which is an 1/8” to 3/8” mine is right at a 1/4” of an inch which is find. You need the clearance so as the clutch wears the release bearing doesn’t hold the clutch disengaged and burn up the release bearing itself

Chained_360 · Feb 7, 2018

Looking good! Can't wait to see more progress

darndart · Feb 7, 2018

Looking forward to seeing pics of the tunnel fitment and what modifications are needed.

hemi446 · Feb 7, 2018

If the master and slave cylinder work ok I’m planning on pulling the transmission on Saturday or Sunday and then the measuring and cutting the floor and torsion bar cross member. I’m using an America Powertrain cross member so it hooks around the torsion bar end sockets and clamps to the frame to stiffen it because of the cut. I talked to one of there salesman and was told they have a customer running low nines in a Duster and nothing has happened to the frame. I hope it works as advertised

RBConvert · Feb 7, 2018

I bought the Dart with an old Keisler Engineering Tremec already installed. I love it. With the 360 crate motor and 4.11's out back, the car launches hard, and on the freeway turns 2100 rpm @ 65 mph. I noticed your bell has Keisler stamped on it.

Just a thought - since the interior is stripped down and you're cutting up the floor anyway, now's a good time to weld up some subframe connectors if you haven't already.

hemi446 · Feb 8, 2018

RBConvert said:
I bought the Dart with an old Keisler Engineering Tremec already installed. I love it. With the 360 crate motor and 4.11's out back, the car launches hard, and on the freeway turns 2100 rpm @ 65 mph. I noticed your bell has Keisler stamped on it.

Just a thought - since the interior is stripped down and you're cutting up the floor anyway, now's a good time to weld up some subframe connectors if you haven't already.

When I put this car together I had a set of old Mopar Performance bolt in frame connectors left from another Barracuda that I installed but welded them in instead of bolting the car is very stiff the door seems have never changed even with it being a convertible
I guess when I do get to cutting the floor out you will be able to see them in the pictures

darndart · Feb 8, 2018

is this the same hydraulic clutch kit you used?

hemi446 · Feb 8, 2018

No the kit I have is like the one that Silver Sport Transmissions sells and it’s like the old Keisler transmission kit
The TREMEC transmission I have is a 1 1/8” x 26 spline input which is a Ford input shaft

coalman · Feb 8, 2018

If any of you are interested, Silver Sport has their installation instructions for "A" Bodies on their Web Site....

darndart · Feb 8, 2018

the hydraulic clutch kit I got from American Powertrain says it fits Ford Tremec or 18 spline Mopar 833.

hemi446 · Feb 9, 2018

So here is the master cylinder and slave cylinder test fixture I slapped together to make sure everything is working. Now I’m just trying to get the air out of the system. if everything works Saturday I’ll try and get the trans out the headers are the biggest problem it takes me about 4 hours a side to remove them because of the 16 bolts on each header plus they run around everything

hemi446 · Feb 10, 2018

Today was a good day I got the automatic out without having to remove at least one header.
I swapped to pinion flange for a Mark Williams with the u bolts and a 1350 u-joint. Some how I just don’t trust the little straps and 1/4” bolts to get the job done.
Tomorrow I’ll start cutting the floor I’m going to install the bell housing and measure back the to were the shifter will come up through the floor and cut the top of the tunnel about 4” wide for a start.
I’m also planning on test fitting the new cross member and cutting the top of the torsion bar frame rail out I think that’s about were the shifter is going to be located.
So more pictures after the cutting.
I still haven’t got all the air out of the slave cylinder with the line going into the top of the cylinder and the dip in the line I may have to try and put a vacuum on it to draw the air out. When I push the master cylinder the 1.4” it is supposed to travel the one disc is free but the output shaft still turns. I’m ordering a slip yoke on Monday so I can slide it in the trans and see if I can hold it while the clutch is being pushed down and the crank being turned.

hemi446 · Feb 16, 2018

Ok so over the weekend I started cutting the floor out for the Tremec transmission to fit.
I installed the bellhousing and measured to the back of the shifter housing which is about 21". I started with a cut from were the tunnel narrows back to the 21" mark which was were the original housing for the floor shifter was welded to the floor. This cut does go through the torsion bar cross member. I also made the cut about 9 1/2" wide because the transmission is 9" wide and the sides are straight up and down for the most part. There are some tabs on the side of the case which stick out a little farther but I didn't want to have to make the cut too wide and the filler tunnel from American Powertrain won't cover the cut.
I also had to cut the torsion bar crossmember back to the inner bolt holes on both sides. You can see the tube in the one picture. I'm going to weld the tube to whats left of the cross member. Just to hold it in place, but without that much cutting the tabs on the side of the case wouldn't move past the crossmember area. If you had a different engine and the head didn't hit the fire wall you could tilt the engine more and the transmission would slide in easier.
With the transmission in I can almost move it up into position but with the the mount on it, it still hits the floor in the front it looks like I need to cut 4-41/2" forward to get it up a little higher.
I'm also thinking of cutting the replacement tunnel and making the rear section a seperate piece because with the shifter assembly installed I don't think the transmission will drop down enough for the shifter stub to come out of the hole.
So this is were I'm at right now.

hemi446 · Mar 3, 2018

So after the power was back on at the house I could get over to the shop and keep working.
It took 3-4 times of putting the transmission in and out to get the opening in the floor to the correct size, and the transmission went in without hitting. I do have to tilt and adjust the transmission to clear the torsion bar cross member. But that to real big deal when the car is up in the air.
I welded in the transmission tunnel it has about 3/8 of an inch all the way around the top of the transmission. I wanted to keep it as close as I could without it rubbing, in the back I did have to dimple the tunnel. Where the back two shifter bolts are because when you turn the shifter assembly around to move it forward to more of the stock A-body location they where touching just a little.
The shifter will have to be installed from the top when the transmission is bolted up but before it's raised up so the cross member can be put in.
I had thought about making the back half of the tunnel removable but it's real easy to put the shifter in from the top and tighten the first four bolts from the top and the back two from the bottom.
With the tunnel welded in I used some 3M Flexible Foam ( part # 08463 ) to fill the gap between the old floor and the tunnel.
I used the 3M product because it doesn't hold moisture like the spray foam you would use on your house. I have seen people use that stuff to fill gaps in floor boards and a year later the floor are rusting out.
There is no way to weld the old floor and tunnel from the bottom the gap is about 5/8" in some places because of the shape of the floor, and I didn't want to keep cutting the floor back to the tunnel then the torsion bar cross member would have less to support it.
After the foam sets up I"ll trim it back to the edges, and after I weld the front bracket for the console in. Undercoat the tunnel and floor you will not see and difference in the floor.
The foam set-up in about 10 mins so I went ahead and trimmed it up. it's a lot harder than you think it sitcks to everything and has to be removed with a razor blade and a box cutter but once your done the gaps are filled real good and the undercoat will seal everything once and for all.