273 and push button

Hey how’s it going!

My 64 currently has a slant 6 with a push button 904 transmission. I have a lead on a 69 273 V8 with 904 transmission.

Questions
Will the 273 bolt right up to my current 1964 904 Transmission? Can I use the 1969 transmission with push button mechanism? Any advantage in using the 1969 904?

Any info I would appreciate it.

To answer your first question, no the 273 will not bolt up to the /6 904; you will have to use a small block auto (like the one you have). I have no clue on the second question though. My thought would be you should be able to make it work, but I can't confirm this.

The 69 273 should have the large diameter crankshaft register. You will need a small block 904 from 67 or later that has the large torque converter nose. 65'

You could search out eather a 64 or 65 small block 904; they are cable operated; with a converter, get a spacer ring made for the converter hub, if needed, bolt it all together.

JBurch said:

You could search out eather a 64 or 65 small block 904; they are cable operated; with a converter, get a spacer ring made for the converter hub, if needed, bolt it all together.

Click to expand...

Just be aware that if you want something higher than a stock stall converter you will have to have it made. Early hi stall converters are not readily available off the shelf. 65'

The 904 from the '64 slant will not fit the 273.
Imperial services used to offer a kit to make the later 904s work with the pushbutton shift mechanism, but their availability has been pretty sketchy the past few years.
You will need a different driveshaft for the '69 904, your '64 has a ball and trunion driveshaft and the '69 transmission uses a slip yoke.
Your slant 6 car uses a different throttle pedal and linkage than a V8.
There COULD be clearance issues with the '69 kickdown linkage when used in the '64.
You didn't say if your '64 is a Barracuda/Valiant or a Dart.
Easiest solution:
Get a steering column from a '66 A body, complete with shift linkage and swap it in. They come in both power and manual steering lengths, get the one you need. This will allow you to shift the '69 transmission.
Get a 904 driveshaft from a '66 Barracuda/Valiant or Dart (they are 2 different lengths)- whichever one you need. This will allow you to use the '69 transmission.
Get the throttle pedal/ linkage and kickdown linkage from a V8 early A body.
Locate some V8 engine mount brackets from an early A body (early A is '66 and earlier, by the way).
Get a V8 steering center link. They have a larger center drop for V8 oil pan clearance.
You will also need the early V8 radiator (the '69 one can work).
Seriously consider upgrading your brakes/torsion bars.
On second thought, the easiest solution is:
Freshen up your current slant 6/904 combination. They're not so bad!

^^^^^^what he said with some caveats. Now, if you want to keep the push button, and not have to change half the car over, find a '64 904 from a 273 and use the reducer ring like jburch mentioned. You can reuse your torque converter if you need to. It's the same as the '64-6 273 one. Changing to the '66 and up transmissions have some advantages though. You have a more reliable linkage shift instead of expensive and tempermental cables, in a '69 model, you can operate your backup lights from the transmission instead of a shifter switch, parts are easier to get, and you have a cheaper and easier driveshaft to repair. Depending on some of your other options (like P/S, A/C, etc) finding the 6cly to V8 conversion parts will be the toughest and most expensive items. The '69 radiator might not work without modification. They tend to sit too high and interfere with closing hoods on some models. You may also have to either change the '69 oil pan to a '64-6 type, or modify it slightly (a big hammer to one corner!) to keep it from rubbing the K-member. Not all swaps need this for some reason, but, some definitely do. You also get into exhaust costs too. None of your slant 6 stuff will work properly. Then you start going faster, and your 9" drum brakes aren't near good enough, and the 7 1/4 rear is on borrowed time too. The 13" wheels won't fit disc brakes, or even some of the 10 drums.......you can see how this can snowball.