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Tremec 5 speed conversion in a 1970 Charger

Kern Dog

Life is full of turns. Build your car to handle.
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Here we go!

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I am finally going to do it. The 727 is coming out and a Tremec TKO600 is going in.
 
Should be fun.... What ratios? And what axle gear do you plan to use?
 
The A-855 Mopar 5 speed is a direct (absolute bolt-in) brute transmission. You should call John Huff for any questions at 307-262-0125. He is awesome to work with and if he has them tested and ready to go, there is no wait.
 
Take your time with the install! Keep us posted, and yes you car does look pretty nice... Pull that chunk and slide some deeper gears in too make use of the extra overdrive! Lol
 
might do it one day with my charger if I don't like the high stall 727 with a RMVB,


or go crazy and get a Lenco...
 
This swap and the thread have been bandied about for a little while.
I have owned this car since March 2000. It was built as an XP29 Charger. In 1970, that meant a mid trim level Charger 500. This was not like the 1969 Charger 500 though, in 1970, the "500" was just a trim level that had nothing to do with racing. The "500" models got bucket seats, floor console, a clock in the dash, an aluminum tail panel bezel that ran the width of the taillight panel and a few more odds and ends. This car was built with a 318 and a 904.
When I bought the car I had immediate plans for a 440. I'd never had a big block car so this was my chance. I liked manual transmissions in theory but wanted to keep this car an automatic. I still had a '76 Camaro with a 350 and a Saginaw 4 speed. That was a fun car.
After a few years of tooling around with a 3 speed automatic and 4.10 gears, I looked at overdrive options. The 518 was considered a few times. In 2012 I scored a good deal on a used but rebuilt Gear Vendors overdrive.
The Gear Vendors bolted in place of the stock tail shaft housing. It only has a .78 overdrive but it still knocked a 4.10 gear to a 3.20 final drive. The reduction in freeway RPMs was great. The GV carried with it some drawbacks though.
The unit I had was an early version with NO provisions for a floor shifter. A bracket had to be made but it left the vertical shifter shaft at an angle that affected the range and feel of the shifter. It sometimes would fail to engage PARK, a problem that would go away with some adjustments that resulted in the inability to engage 1st gear. The output was a yoke instead of a splined shaft so I had to use a slip and spline drive shaft like you'd see on the front of a 4 wd truck. The shaft was built custom locally. The drive line angles were off a bit too. I dealt with some vibrations that negated some of the benefits of quieter freeway cruising. Sometimes, the GV would stick in OD as I slowed to a stop so it was like I was always running a 3.20 gear. There goes my "out of the hole" punch that these deep gears are supposed to give! By 2014, I decided to pull the GV and go back to direct drive. I sold it to a guy in Tennessee and he has been real happy with it.
Since then, I have gone back and forth about what I want to do. I stumbled across another 518 in 2018. This was a fresh rebuild with 618 internals but it was also an electronic version that needed a stand alone computer OR a manual valve body to work. Oh yeah, AND a Big Block bell housing conversion. Plus, they still need extensive modifications to the torsion bar crossmember and trans mount.
No thanks.
In January 2019, I sent an email to Silver Sport Transmissions. I asked about the transmission kits that they offer. The man responded with a nicely detailed list of choices and pricing. I was working a job out of town and HATING it so I just put the idea of the 5 speed swap on the back burner on "simmer".
 
One of the stumbling blocks for making a leap like this has been the cost. Looking at this from a "it will get better mileage" perspective is not at all sensible. I'll probably never drive it enough to save that much gas money even if it were to get 100 mpg after this swap.
For awhile, I actually considered the 4 speed automatic swap. One reason that I dismissed that is that IF I were going to spend $6000 or more, I wanted a more dramatic change in the car. An automatic with one more gear didn't seem dramatic enough. The 727 works great, it just needed another gear. A manual trans though....Now THAT is a dramatic difference in the driving experience.
SST 9.jpg
 
One of the stumbling blocks for making a leap like this has been the cost. Looking at this from a "it will get better mileage" perspective is not at all sensible. I'll probably never drive it enough to save that much gas money even if it were to get 100 mpg after this swap.
For awhile, I actually considered the 4 speed automatic swap. One reason that I dismissed that is that IF I were going to spend $6000 or more, I wanted a more dramatic change in the car. An automatic with one more gear didn't seem dramatic enough. The 727 works great, it just needed another gear. A manual trans though....Now THAT is a dramatic difference in the driving experience.View attachment 1050941
coulda just got a gearvendors
 
My friend just ordered the same transmission for his 71 Charger R/T. It will be worth the work and the money,when you are rowing the pistol grip through the gears!
 
I’m lurking, I mean following.
I’m doing a 440/833 conversion from 318/904 in my ‘70 Coronet.
Spent all of the money, got all of the parts. So far have only put the shifter hole in the floor.
I need to follow you for inspiration/motivation.
BTW, Kern, was that your cars original colour? It looks great!
 
This car came out of St Louis in December 1969 in THIS color:
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I wish that I had better pictures of the "before". F8 in and out, white vinyl top, A/C but with 4 wheel 10" drum brakes!
 
Bear with me, guys....I have been wanting to set this story up to tell in a way that should be helpful and entertaining. If this NON tech talk bores you, I understand if you skip ahead.
Back on track....
I love this car. I've been on countless cruises in town as well as 4 road trips of approx 1000 miles round trip. 3 of them were with the Gear Vendors, the first was with a 3.23 open diff. The lower cruising RPMs really does make a difference.
I have had a few low geared vehicles that just leave me frazzled and tired after a long drive. The 2 old Dodge trucks that I have owned scramble my brain after a hour at freeway speeds. It makes me wonder how people just tolerated this when they were new.
Like I stated, I love this car but for the last couple of years, it has felt a bit stale. I needed a change. The 440/493 runs strong. I did consider swapping the Lunati cam I had in there a few years back. The car was an animal with that cam! I decided against that for a few reasons. The low speed operation with the bigger cam was a bit soft, the power brakes required a vacuum pump too.
I still like the looks of the car so I wasn't about to change the color or the wheels, yet....
I posted a few threads about overdrive options. A few members suggested a manual transmission. I dismissed the idea but after a little while, the idea took root. Being a cheap minded dude, I needed to find a way to pay for it without spending my own money.

September 2019, I bought THIS fine car:
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The car came with the original 383 but was missing a LOT of parts. I rebuilt the engine but needed a good 727, converter, drive shaft, cooler and lines, shift linkage and Kickdown linkage or cable.

Repair 61.jpg
Repair 65.jpg
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I got to the point where I needed to buy all that stuff to get "Jigsaw" running and driving.
The thing is, I already have all of those parts in excellent working order....currently in THIS car:

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To buy that $5000 project Charger, I sold off some parts and kicked in about $1500 of my own money.
For this transmission swap, I am selling THIS car:

Drat 15.jpg

The Dart is the proverbial "Fell into my lap" car. December 2015, a car club buddy called me..."Hey, do you know anyone that might want a '65 Dart? $600 and it comes with a bunch of parts!"
Yeah...I know a guy.
I sold the parts....which paid for the car entirely. I had it on ebay before Christmas and it didn't make the reserve. I'll try again soon.

In late November, I decided to move ahead with this Tremec swap. It would give me the 727 stuff I needed for "Jigsaw" and also provide a nice change of pace for "Ginger", the red one.
 
I placed the order in early December. The TKO series seems to be fading out as the new TKX (or whatever the new one is called) is gaining popularity. This may have been why the price I paid was far lower than the quote I got in early 2019....It was like buying day old donuts that still tasted fine!
For $5978 I got the whole she-bang. TKO600 series in the Close ratio. 1st: 2.87 2nd: 1.89 3rd: 1.28 4th: 1.0 5th .64. Hydraulic clutch. Pedals, bell housing, Pistol Grip lever, steel flywheel, SST TRK clutch, electronic speed sensor, floor plate and a bunch of other small parts.
The transmission arrived first, one of 6 boxes to arrive.

SST 10.jpg
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Jigsaw has a bench seat and column shift for now but I do have a bare console and bucket seats that will make their way into the car eventually.
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Yeah, it looks like crap...I am quite aware of that!

The spare console that came with "Jigsaw" really is bare....NO carpet or border trim, no courtesy lights and NO top plates. Ginger has all of those things in good condition. More parts sharing! Here is the console in Ginger:
G console 4.jpg
G console 5.jpg


I will be keeping a console in Ginger. I knew that the automatics and the 4 speed cars used a different top plate for the console. This SST kit is supposed to put the shifter in the stock location as the 4 speed cars. 4 speed stuff is harder to find but I have read from others that have taken A/T console plates and just modified the opening. Great idea!
A FBBO member came through with a fair price on some console parts:

SST 22.jpg
SST 23.jpg
G console 1.jpg
 
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