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Tremec TKX 5-Speed Conversion

I have the SST TKX in the ‘68 Coronet and would do it again in a heartbeat. Few things, indexing the bell housing is critical and will most likely require offset dowels. You will need to do a mock up first and measure before you know what you need so add a week for the mailman to your schedule, lift time.
SST is very adamant about checking and correcting the TIR. Their warranty is only good if you send proof of verification and alignment. To that end, I ordered two sets of offset dowels from Robb Mc; they'll accept returns on the unused pair. The Robb dowels are .496" diameter; most parts houses like Summit sell the Mopar/Ford dowel which is .500". Works for Fords but I've heard the horror stories trying to pound them into a Mopar block.

20230928_190036.jpg

I didn't have a dial indicator to measure the runout. This is one of those instances where I need a tool I may never use again. I wasn't going to spend hundreds of dollars on a Starrett indicator and Noga base, but not HF either. I settled on a Wen dial indicator and Clockwise base. Machinists may roll their eyes on the Wen, but it got 785 reviews on Amazon with a 4.5 star average. The base seems to hold:

20230928_190213.jpg
20230928_190536.jpg
 
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Did you get the standard bell housing? Or the Quick Time bell?
Local guy bought the Q/T bell & it wound up being over .060 out of alignment... I machined custom offset dowels to get if in the ballpark... Then the bolt holes needed to be opened up... He scrapped the Q/T & bought a regular bell, it was within .006 out of the box..
 
The Wylwood slave cylinder is far superior to the OPB chinesium crap. I do not know why SST would include that junk in such an expensive package. If they sent that one, change it to or you will be back underneath when it fails internally. There are actually 2 choices on the slave throw. .75” and .625”. They do not give you a choice but they should. The .625” gives a much shorter throw but delivers a heavy pedal. I have run both and kept the .625” in place. It depends on your driving style but for slamming gears I want it short and to feel the pedal. You will need to make a pedal stop that is not included in the kit. You can blow out the slave cylinder if you do not do this. It also lets you customize your engagement/release point to your liking.
Yes, the kit came with the OBP master cylinder. Disappointing since the TKO's came with Wilwood. Haven't decided what to do yet. There's no mention in the paperwork about the slave throw. I'm going to call SST and ask about it.
 
Did you get the standard bell housing? Or the Quick Time bell?
Local guy bought the Q/T bell & it wound up being over .060 out of alignment... I machined custom offset dowels to get if in the ballpark... Then the bolt holes needed to be opened up... He scrapped the Q/T & bought a regular bell, it was within .006 out of the box..
I didn't special order a QT bell and there's no mention on the order or markings on the bell so it must be the standard.
 
One advantage of the TKX is supposed to be the ability to shift better at RPMs over 6000.
My TKO is a bit stiff when trying to power shift at 6000 or thereabouts. It probably isn't important though if the engine HP peaks below that. I just get so excited when driving fast and hard, I am caught up in the moment and the engine speed gets away from me.
Any idea of where your 440 tops out?
 
Does your w
I have the SST TKX in the ‘68 Coronet and would do it again in a heartbeat. Few things, indexing the bell housing is critical and will most likely require offset dowels. You will need to do a mock up first and measure before you know what you need so add a week for the mailman to your schedule, lift time.
The Wylwood slave cylinder is far superior to the OCB(sp?) chinesium crap. I do not know why SST would include that junk in such an expensive package. If they sent that one, change it to or you will be back underneath when it fails internally. There are actually 2 choices on the slave throw. .75” and .625”. They do not give you a choice but they should. The .625” gives a much shorter throw but delivers a heavy pedal. I have run both and kept the .625” in place. It depends on your driving style but for slamming gears I want it short and to feel the pedal. You will need to make a pedal stop that is not included in the kit. You can blow out the slave cylinder if you do not do this. It also lets you customize your engagement/release point to your liking.
If on install,it will not close on that last 1/2”, do not force it. The splines are not lined up. I think the original alignment tool that they were sending out was just a hair small(now corrected). I had to get the clutch engaged to get it installed. Much easier said than done on your back with an uninstalled transmission hanging in the air.
I am sure that Kerndog can add a few inputs to keep you from making some of the stupid mistakes that we fought thru.
This one?

IMG_2660.jpeg
 
Started working Saturday morning; the goal was to install the foot pedals. I didn't want to monopolize Greg's shop space so I did the ground-level work at home. First thing is to remove the front seats, accelerator pedal and front half of the carpeting. Over the years I've had to crawl under the dash too many times to troubleshoot and fix things. Ironically, the last time was earlier this year to install a new speedo cable, one that isn't compatible with the Tremec.
I can remove each front bucket in about 5 minutes, without jacking up the car. A deep socket on the outside bolts, and my arms are long enough to reach over to the inside bolts with a ratcheting box wrench. In 35 minutes the front of the interior was stripped. It was only 10:05 am, I'll be done by lunch. Yeah right!
It was new carpeting installed during the resto so its going back in. Before reassembling the interior back in the day I covered the floor, firewall, and inside door panels in Fat Mat. BTW, this is why you never glue down carpeting. The door sills, kick panels, and seats hold it down just fine. Even if you think you'll never need to pull it up again, one day you'll want to pull it up again.
The brackets on the hump are for the buddy seat. I had the seats bolstered when they were recovered, and later I installed XV Engineering 3-pt seat belts. The combination leaves no room for the buddy seat. It's kind of a bummer because I'd like to reinstall it. After I'm retired I'll have to spend some time noodling on it.

20230923_111847.jpg
20230923_114917.jpg

In my case, some of the Fat Mat adhesive stuck to the jute backing.
20230923_114537.jpg

A tip, or maybe an idiosyncrasy: I'm a firm believer in bagging and tagging, to the extreme. Except in cases where I can keep the nut or bolt with the item. The door sills have different screws to hold it down; on type on the door sill itself and two longer ones that have to penetrate the carpet to screw into the floor pan. I hold them in place with painters tape and set the item aside where it won't be disturbed. Makes it that much easier to reinstall.

20230923_105411.jpg
 
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Looking at the instructions, swapping the pedals should be a straightforward operation. But first, lets talk about the instructions. On the whole, SST's instructions are pretty good. They're very detailed on the assembly, very vague on the disassembly. I get it, the disassembly is a one-size fits all guideline, while the assembly is Tremec specific. For the pedals, there's only 5 steps to disassembly, and 20 for reassembly.

20230928_192608.jpg

Step #3: remove pivot pin nut from RH side of housing. Two minute job. But the Coronet has another bracket attached to the brake cage that shrouds the nut. I spent waaay too much time trying to reach the nut with the bracket in place. Can't be done - have to remove the bracket. The bracket is attached to the cage with three bolts and a nut. I removed two bolts and the nut and the bracket wouldn't move. WTF?? I finally realized that one of the bolts also holds a U-shaped bracket that supports the main wiring harness. The harness was obscuring the bolt head. Pop off the harness, bend down the bracket a little to expose the bolt head, and off it came. Now the pin nut is exposed. I spent over an hour on this part alone; knowing what I know now it can removed in minutes.
The big bolt head in the center of the pic is the bolt that connects the brake pushrod to the brake pedal; it has to come out. Also notice the tape with "7" still stuck to the brake light switch; it's leftover from the restoration when I catalogued all the wiring harness terminals.
20230923_124211.jpg

Looking up at the bracket; here's one of the attachment points, and also the hidden wiring harness bracket bolt.
20230923_143731.jpg

The hidden nut: It pays to take lots of pictures before disassembly
20230923_150108.jpg

The offending bracket out of its element:

20230923_152553.jpg
 
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Looking at the instructions, swapping the pedals should be a straightforward operation. But first, lets talk about the instructions. On the whole, SST's instructions are pretty good. They're very detailed on the assembly, very vague on the disassembly. I get it, the disassembly is a one-size fits all guideline, while the assembly is Tremec specific. For the pedals, there's only 4 steps to disassembly, and 20 for reassembly.

View attachment 1531917
I had to learn as I went. I saw that the cowl vent had to come out to get the long pin out that both the clutch and brake pedals hinge from.

Regarding the speedometer. I'm guessing they included an electronic speed sensor/Pulse Generator that allows you to attach a stock speedometer cable?
The TKO speedo sensor is on the right/passenger side so if the TKX is as well, you'd need an extension cable to reach without binding.
 
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One advantage of the TKX is supposed to be the ability to shift better at RPMs over 6000.
My TKO is a bit stiff when trying to power shift at 6000 or thereabouts. It probably isn't important though if the engine HP peaks below that. I just get so excited when driving fast and hard, I am caught up in the moment and the engine speed gets away from me.
Any idea of where your 440 tops out?
I don't. I've taken it down Sac raceway a few times during Mopars at the Strip, but I didn't get any good runs in.
 
I had to learn as I went. I saw that the cowl vent had to come out to get the long pin out that both the clutch and brake pedals hinge from.

Regarding the speedometer. I'm guessing they included an electronic speed sensor/Pulse Generator that allows you to attach a stock speedometer cable?
Its a stock analog speedo, so the cable is OEM on the one end and Tremec specific on the other.
 
Am I understanding that they include a hybrid speedometer cable?
If not....
You may need to call them. I have a Dakota Digital electronic gauge cluster and got lucky that the speedometer sensor in the transmission was directly compatible. The majority of Tremec swaps are probably into cars with stock, cable driven speedometers so SST should have a fix for you.
 
Looking at the instructions, swapping the pedals should be a straightforward operation. But first, lets talk about the instructions. On the whole, SST's instructions are pretty good. They're very detailed on the assembly, very vague on the disassembly. I get it, the disassembly is a one-size fits all guideline, while the assembly is Tremec specific. For the pedals, there's only 5 steps to disassembly, and 20 for reassembly.

View attachment 1531917
Step #3: remove pivot pin nut from RH side of housing. Two minute job. But the Coronet has another bracket attached to the brake cage that shrouds the nut. I spent waaay too much time trying to reach the nut with the bracket in place. Can't be done - have to remove the bracket. The bracket is attached to the cage with three bolts and a nut. I removed two bolts and nut and the bracket wouldn't move. WTF?? I finally realized that one of the bolts also holds a U-shaped bracket that supports the main wiring harness. The harness was obscuring the bolt head. Pop off the harness, bend down the bracket a little to expose the bolt head, and off it came. Now the pin nut is exposed. I spent over an hour on this part alone; knowing what I know now it can removed in minutes.

View attachment 1531918

View attachment 1531919
The hidden nut:
View attachment 1531920
Here are a few pictures I found online.

01 69 A.jpg


01 69 B.jpg


01 69 C.jpg


These are from a 69 Charger.
My '70 looked different.
 
SST is very adamant about checking and correcting the TIR. Their warranty is only good if you send proof of verification and alignment. To that end, I ordered two sets of offset dowels from Robb Mc; they'll accept returns on the unused pair. The Robb dowels are .496" diameter; most parts houses like Summit sell the Mopar/Ford dowel which is .500". Works for Fords but I've heard the horror stories trying to pound them into a Mopar block.

View attachment 1531877
I didn't have a dial indicator to measure the runout. This is one of those instances where I need a tool I may never use again. I wasn't going to spend hundreds of dollars on a Starrett indicator and Noga base, but not HF either. I settled on a Wen dial indicator and Clockwise base. Machinists may roll their eyes on the Wen, but it got 785 reviews on Amazon with a 4.5 star average. The base seems to hold:

View attachment 1531884 View attachment 1531885
I needed the .007" offset and used the same ones you have. The hardest part is understanding which way to move them. If you draw it on paper it makes sense.
 
Yes on the OBP slave. I think it made it 900 miles. The pedal got soft so I bled it again and that lasted 2 days. The very black fluid should have been a tell. Aluminum shavings turn black in brake fluid. The OBP was leaking internally on it own seal. One could argue that I missed the shaft alignment(it can be shimmed East to West) and that the now not true angle was causing cylinder wear and thus failure. The Wilwood has been in place for 9000 miles with the same shim angle.

On the cylinder size (.750" vs .625"), SST does not give you a choice. I assume they they think the customer base wants the easier pedal with longer throw. For a comparison I have a '94 Dodge 2500 with the Cummins. The .625” would be a 20% easier pedal than the truck and the .750”would be a 20% stiffer pedal than the truck.
 
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