Manual Transmission Options

[70 Challenger Lover]

Gearing up for my next build...another 70 Challenger but this time a base model I plan to customize and keep. I have the numbers matching 4 speed and would never get rid of it but I was thinking I'd like an OD unit to really make the car even more fun. I have a Tremec in my Vette and love it.

I see Passon has a nice one but at $6k, I'd like to consider other affordable options. Plus waiting in the dark for years on end is unacceptable. I was thinking of the TKO 500 or 600. I'd go with a hydraulic clutch and maybe even diaphragm instead of borg and beck. I want to get away from the annoying over center spring. Not worried about floor and brace modifications since the car is still a shell. The t56 is overkill for my 383. Open to other option if the base trans isn't over 4K.

So my question is, Do you use an adapter kit? Their website says you do but I can't find the kit. Do you start with a model intended for ford or gm? I'd like to figure out the process before buying anything.

[Brads70]

economically I found a T56 from a 95 Camaro locally for a pretty cheap price and then converted it to LS1 specs with a kit ( makes the input shaft longer and more common/useable I'll have just under 2K CANADIAN into the T56  ( about $1500 USD )
http://www.superchevy.com/how-to/ghtp-1203-lt1-t56-adaption-new-version-conversion

This is going in my 71 Javelin, cheap(er) and should make the car more versatile.  Transmission doesn't care what car its in...    Food for thought....... Look around see what is available?   

Adapter bellhousings are available to make almost anything work......

[70 Challenger Lover]

I know the input shaft will need to be a certain length and the tip a certain diameter to fit into the pilot bushing. I figured I'd need a specific bell housing but that could alter how far the input shaft expends into the rear of the crank shaft. Is it better to start with a trans designed for a ford or GM? Is there a better option?

[1 Wild R/T]

Adapting the input shaft is doable, also be aware of shifter location, I know Tremec offers at least three locations... If you don't mind cutting the floor then you have options but obviously the further forward mounts can be problematic as you run the shifter into the dash.....   

Those F body GM's have the engine shoved under the cowl so the shifter is further forward.... Might not be ideal...

[70 Challenger Lover]

I was hoping that someone here had gone through all this and had the best tricks.

[Rich G.]

I did mine years ago and if I remember correctly they modified my bell housing and installed an adapter plate. I just looked at the Silver Sport Transmission website and they don't say anything about the bell housing. I wonder if they redesigned the trans???

[Brads70]

I know the input shaft will need to be a certain length and the tip a certain diameter to fit into the pilot bushing. I figured I'd need a specific bell housing but that could alter how far the input shaft expends into the rear of the crank shaft. Is it better to start with a trans designed for a ford or GM? Is there a better option?

I chose the GM input shaft length(LS1) because it opens up the most options  when you get into clutches etc... and easier/common to get. The pilot bushing can easily be made to what ever you need.
The shifter location on the T56 I have is perfect for my application, its at the back, pretty close to the stock shifter location. I like most people have to watch what I spend so this I felt was a pretty economical solution for what I wanted to accomplish. Heck the stock pistol grip shifter even bolts right up without any modifications!    Pictures are for the adapter plate to midplate  that I made to adapt a stock Jeep bellhousing to the T56. I could have just bought an adapter bellhousing but doing it myself saved at least a grand.

[Brads70]

Here are a few pictures of installing the LS1 kit , new input shaft and midplate. I have never done this job before but it was really simple to do!   Just posting to encourage you to consider this option..... its not difficult or expensive?   Those T56's from 95-99? Camaro's/Firebirds are pretty easy to find and relatively cheap as in stock form they only are good for those cars they came out of. With the adapter kit it makes them much more versatile. 

[GoodysGotaCuda]

I run a T56 magnum in my 'Cuda, outstanding trans, but get the sawzall out!

[Racer57]

I talked to these guys at the Hot Rod Power Tour a couple years ago. They seemed to be very knowledgeable.  I have an older 5-speed Tremec in mine. The hump had to be cut, but after the new plate was put in, you'll never know its any different. The web site wasn't cooperating with me, but give them a call.
  https://americanpowertrain.com/body_type/mopar-e-body/

[70 Challenger Lover]

No wonder everyone got so excited about the Passon bolt in units. The Tremec route seems like a lot of trouble and unless I find a decent one from a junkyard, the cost gets up there once you add in a different bell housing. I guess I thought there were easier options out there.

So those who are running a t56, the shifter handle in roughly in the right spot?

[Chryco Psycho]

2 other options Not mentioned yet is the A*33 OD version , it is a 4 ratio trans with OD , very wide ratio but usually $300 or so & it is a bolt in with some minor changes . I have done at least 20 of these swaps , only one person asked me to remove it .
Passon Also make a 4 ratio OD with better ratios for a lot less than the A855 5 spd with od , it is also a bolt in using an 18 spline clutch disc

[70 Challenger Lover]

I just saw the Silver Sport Transmission site. Looks like they offer the entire package ready to drop into an e body and they claim the shifter is in the same spot. Some tunnel work needed but that's okay. I'll have to get a quote from them. This is what I had in mind.

[Brads70]

I just saw the Silver Sport Transmission site. Looks like they offer the entire package ready to drop into an e body and they claim the shifter is in the same spot. Some tunnel work needed but that's okay. I'll have to get a quote from them. This is what I had in mind.

In past years gone by I've heard lots of issues with the 5 speed Tremec conversions....... do your research! 

[Chryco Psycho]

I have experienced problems shifting fast & heard of broken syncro rings when trying , , bigger versions such as the T 56 magnum & the T6060 seem to hold up to the power just fine but then you are doing massive cutting to the tunnel to get them to fit