Transmission advice

[booyaballer]

I have a 70 Challenger with a 360 six pack crate engine.  originally, it was a column shift car (based on my steering column) which was converted to a floor shifting automatic with a 727 tranny.  I plan to convert it to a manual transmission but don't know what transmission I should consider.  I'm open to any tranny whether a 4, 5 or 6 speed.  my only concern is avoiding making big modifications to fit the tranny.  I want to avoid cutting the floor if possible.  Thoughts?

[Chryco Psycho]

The best / strongest , easiest to fit is still the A833
there are a number of versions
23 spline which will be fine for you or the Hemi 18 spline
You can get the 833 in different ratios closer or wider ratio or even the Truck 833 which uses 3rd as Overdrive
Passon also has a hemi OD unit with closer ratios than the truck unit , any of these are a bolt in with no real modifications .
Trmec offers a nuber of solutions also they have a 5 speed which barely fits with some tweaking but it doesn't shift as well , there is also the Viper T56 Magnum 6 speed  but now you are cutting big time .
Honestly the 833 is the heapest & easiest to fit & works the best as well as being the strongest option except maybe the T56
I have done a number of swaps using almost all of the available trans options

[Cuda Cody]

You'll have to cut the floor to go from an Auto to a Manual for the 4 speed tunnel for pretty much any of the manual trans.  Some fit easier then others, but pretty sure they all need to have the floor cut.  It's not hard, but can be scary if you're not used to cutting sheet metal.  Here's some thoughts on the trans....

https://forum.e-bodies.org/engine-transmission-and-rear-end/4/choosing-a-new-manual-transmission/610/

You'll also need to add a ballstud bracket to the front drivers frame rail.  The rest is pretty simple bolt on stuff like pedals and stuff.  Not a cheap swap if I remember correctly.

[Chryco Psycho]

True the shifter tunnel can be bought restamped as per the original & fits very well , no question where it should be but it has to be cut in to allow for the shifter but will look factory

[Cuda Cody]

@booyaballer  is your car a project or is it all done and driving?  And do you know your rear end ratio?  3.23, 3.55, 3.91, 4.10?

[cataclysm80]

What are the options for the same engine setup with an auto trans?  Gear Vendors overdrive, anything else?

[Chryco Psycho]

GV od is available for auto or 4 spd
The 518 swap is a good one also
both will give you OD

[303 Mopar]

What are the options for the same engine setup with an auto trans?  Gear Vendors overdrive, anything else?

GVOD is a good choice but you still need to modify the tunnel some.  You could also swap to a full manual valve body in the 727 for the feel of shifting.  However, I would strongly suggest you swap to an 833 4 spd regular or OD.  I did this in my '68 Charger and it TOTALLY changed the car, so much more fun to drive now. I bought the entire package from Brewers.  I currently have a full manual 727 in my Cuda and just bought the 833 OD from Passon and will be swapping that over in the next month or so.  Also, you can get on "the list" for the Passon 855 5 spd but it is 3-5 year wait.

[Brads70]

What are the options for the same engine setup with an auto trans?  Gear Vendors overdrive, anything else?

I'm using a Keisler A41 kit (GM 4L60) with no issues 5 years now.....
Keisler is out of business now Silver sport .
https://shiftsst.com/articles/cat/mopar/post/challenger-barracuda-1970-1974-perfectfit-kit/

[booyaballer]

Thank you all for the feedback, this will definitely put me on the right track.

To answer Cuda Cody, i was told the gears are 3.23 though i have not confirmed it.  my car drives except that currently i dropped the reared to have it rebuilt, which is what lead me to start inquiring about the transmission because i figured i would need to possibly change the gears in anticipation of a manual transmission. 

Here's a pic except it currently has an RT hood and the venal top is destroyed. 

[Cuda Cody]

Good looking Challenger!!!

[fc7cuda]

It's a pretty involved project, but if you can install a crate motor then you'll be able to install a manual transmission too.  Good luck! 

[303 Mopar]

my car drives except that currently i dropped the reared to have it rebuilt, which is what lead me to start inquiring about the transmission because i figured i would need to possibly change the gears in anticipation of a manual transmission. 

One more thing to consider, anything you go with except the 833 will require a new (or modified) driveshaft and adjustments to get the angle correct which has cause some issues in the past. 

[HP_Cuda]

And shorten the driveshaft....

What are the options for the same engine setup with an auto trans?  Gear Vendors overdrive, anything else?

GVOD is a good choice but you still need to modify the tunnel some.  You could also swap to a full manual valve body in the 727 for the feel of shifting.  However, I would strongly suggest you swap to an 833 4 spd regular or OD.  I did this in my '68 Charger and it TOTALLY changed the car, so much more fun to drive now. I bought the entire package from Brewers.  I currently have a full manual 727 in my Cuda and just bought the 833 OD from Passon and will be swapping that over in the next month or so.  Also, you can get on "the list" for the Passon 855 5 spd but it is 3-5 year wait.

[cataclysm80]

And shorten the driveshaft....

I had a 904 auto trans & driveshaft, so I have to adjust the driveshaft length just to install a 727 auto.  I figured I'd do the Gear Vendors at the same time.


For the original poster, Is the 727 driveshaft a different length than the 833?