I have a 65 Barracuda with a slant 6 - three on the tree want some transmission/engine advice

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biffbaxter

biffbaxter

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As the title says, I have this car and its working well, and is a very straight driver, but I am considering two paths, and want to ask the mopar experts what path is best. (I am not concerned about numbers matching, etc. just a fun cruiser)

I would be interested in swapping the tranny from a 3 on the tree to either a floor shift or automatic, which path would be easiest to source and get done for that motor. I can do it, but have limited space, so I might source the parts and then either rent the space or have someone do it.

I would not mind keeping the slant six since I know the motor and am not making a hotrod, just a cruiser that is a driver now. The wife will can drive a floor shift stick well, but the non-syncro 3 on the tree is a non-starter for her, so I would not mind making it easier for her, and in traffic frankly.

So would it make more sense to source a 273 auto and rebuild/swap, or just the transimission for a slant six. Just not sure at this point which path has best parts availability and able to work without having to do a ton of mods, and spend 5K.

Thoughts, resources, feedback is welcome.
 
Just know that you will need to cut a large part of the floor and transmission tunnel out and replace it with the four speed floor. You cannot get around it, because the four speed transmission is much wider than the small three speed. I have a 64 Valiant with a hot slant 6 and the same transmission setup. Three on the tree. My wife loves driving it. Teach your wife to drive it and have fun.
 
If she can drive a manual transmission, she can learn 3 on the tree. I bet she will end up liking it, I know I fell in love with it myself.

Your easiest and most cost efficient option would be to swap in the 904 automatic. No modifications to the sheet metal necessary like a 4 or 5 speed.
I personally would not swap a 273 in place of the 225. If you are going through the cost and effort of the motor swap, put a 360 in it.

I would upgrade to a (new)2bbl carburetor on the 225, add a 2.25” exhaust, and dial in the ignition system. Rebuild/buy a 904, aftermarket floor shifter,and spend some money on a torque converter with a 2800 rpm stall.

Even with a stock cam and 1 bbl carb, a modern high stall torque converter would make a noticeable improvement.





But really you should big block swap it.
 
I'm a big fan of slants with three-on-the-tree. You are correct, the A903 top loader trans sucks the big donkey dick, and completely due to the non-synchro first gear. I have one in my 66 Valiant and I hate it. And this is coming form a guy who's spent the last 50 years rowing gears on both a personal and professional basis. I can shift with the best of them, but the A903 first gear is complete crap.

The easy way around this is to get an A230 3-speed and swap it out. It is MUCH stronger, and has all synchro gears.

If we were a year or so down the road, I'd share how I'm going to turn my three-on-the-tree into a four-on-the-tree. It will be theft-proof from any millenial on the planet. :p
 
LOL...love the replies... I would prefer to keep the slanty, but I am not worried about numbers matching (its a factory slant). I had a /6 in another vehicle I drove over 300K so I have a bit of an affection for the engine, and spent some money in a previous life with clifford in another 6 banger (rambler american). Just want not sure how much work a 904 would be to swap (drive shaft, etc). I have done lots of auto work, just newer to most mopars...I appreciate the guidance.
 
halfafish said:
I'm a big fan of slants with three-on-the-tree. You are correct, the A903 top loader trans sucks the big donkey dick, and completely due to the non-synchro first gear. I have one in my 66 Valiant and I hate it. And this is coming form a guy who's spent the last 50 years rowing gears on both a personal and professional basis. I can shift with the best of them, but the A903 first gear is complete crap.

The easy way around this is to get an A230 3-speed and swap it out. It is MUCH stronger, and has all synchro gears.

If we were a year or so down the road, I'd share how I'm going to turn my three-on-the-tree into a four-on-the-tree. It will be theft-proof from any millenial on the planet. :p
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mmm I like the idea of an A230. Did not know that was an option. What considerations would I need to make for a 65, or feel free to point me to posts that give me hints and I will go do some homework. :) - And yes I tell people I don't need a car alarm as nobody under 40 knows how to steal my car...ha
 
biffbaxter said:
And yes I tell people I don't need a car alarm as nobody under 40 knows how to steal my car...ha
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Yes, nobody under 35-40 can drive it.

Sadly, I'm nobody's idea of a guru. The A230 was factory for a whole bunch of Mopars, from slants to big blocks. I got mine from a 73-ish Duster with a 340. They are not unobtanium but you may have to keep your nose to the grindstone to find one.

I'll have to refer you to others that know this business better than myself for making this swap. But I do believe it's a pretty straight forward deal.
 
LOL You DON'T want me to restart the "I can drive a non syncro 3 speed rant"
 
biffbaxter said:
mmm I like the idea of an A230. Did not know that was an option. What considerations would I need to make for a 65, or feel free to point me to posts that give me hints and I will go do some homework. :) - And yes I tell people I don't need a car alarm as nobody under 40 knows how to steal my car...ha
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It's not. Not without the floor modifications I mentioned earlier. If you do that, the A230 will fit. I've tried it. It will not fit otherwise. It's the same basic size as the A833.
 
67Dart273 said:
LOL You DON'T want me to restart the "I can drive a non syncro 3 speed rant"
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How well I know. It's just a non issue with the clutch adjusted correctly. Even Kitty has no problem whatsoever finding 1st gear while still rolling. It's just not difficult at all. I've never understood all the whining either, but there's a lot of it. Not talking about the op here.
 
Because of the wife- I would go with a later model (mechanical floor shifter) /6 automatic. Anyone can drive that and simple.
 
Murray said:
Because of the wife- I would go with a later model (mechanical floor shifter) /6 automatic. Anyone can drive that and simple.
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Might be the best option. He can probably get a good amount for the 65. They aren't doing anything but appreciating right now.
 
Just keep in mind no matter which trans is used, the drive shaft will need to be modified (B&T to slip spline) and there will most likely be some shifter/linkage issues. None of this is a big deal.
 
And also keep in mind that a late model ('68 and up) automatic will have a torque convertor that will not fit the early crank without remachining the flange or getting a custom-built TC (and no, the proper early torque convertor will not fit the later transmission, either- different splines), will require a new driveshaft, speedometer cable, later carburetor with proper kickdown linkage (and also note that the later carburetor, depending on year, may also require a switch to cable throttle linkage), and don't forget that you'll need to swap out the radiator or at least add some type of transmission cooler...
Even the early transmission (pushbutton, cable shift) will require locating all the correct pushbutton and shift cable/park cable bits and pieces- since they are not generally compatible with the majority of aftermarket floor shifters.
At that point, swapping in the A230 (trans tunnel and carpet, speedo, driveshaft) may actually be LESS work...?
 
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The easiest and cheapest would be to swap an A230 3 speed and floor shift linkage into your car. Assuming an A230 will just bolt up to your bellhousing. A230's are cheap and strong. They had good shifters and linkage. The rest would be to find the right length drive shaft and get a manual trans floor tunnel for your Barracuda. Only cut the minimum to fit the floor tunnel and do not cut the cross brace. As mentioned above you may have to change the speedometer gear and get a 66-67 A-Body speedometer cable. A V8 swap adds a lot of extra parts that are special to Early-A V8 cars that might be hard to find.

Brewer's Performance - Mopar A833 4-Speed Transmission and Component Specialists

www.brewersperformance.com www.brewersperformance.com
 
IMO, the easiest and cheapest way to go from your pitiful 903 junk box to a 904 automatic is to find someone parting out a '65 slant 6 automatic and getting the transmission, cables, and steering column. that would be a straight bolt-in....no driveshaft change needed. For a bolt-in slip yoke trans and upgraded yoke/driveshaft, get a '66-7 transmission, and a '66 column with shift linkage. For a floor shift manual trans setup, the '64-5 833's are not too pricey, but, that will require a full shifter with linkage, a slant 6 4 speed bell housing, and a floor cut. You would also need to make sure the crank is drilled for a stock pilot bushing, or, get a conversion bearing for it. There again, the existing driveshaft can be reused. Using a 230 3 speed or later 833 4 speed would need the same conversion, along with the correct slip yoke and driveshaft along with a different bell housing.
 
Here's a 904 transmission and all the kickdown linkage, but shipping may make it a no go, as it's on the other side of the country from you.
www.forabodiesonly.com

[FOR SALE] - 1967 225 Slant six and 904 transmission $200

Slant six and 904 transmission from my 1967 Dodge Dart the odometer reads 60,213. I will throw in the good six cylinder radiator, 9 inch drums and spindles. Located in Bruceton Mills, WV 26525. Ran fine a few months ago before I started pulling it out. Took it out to install a 340.
www.forabodiesonly.com www.forabodiesonly.com
 
halfafish said:
I'm a big fan of slants with three-on-the-tree. You are correct, the A903 top loader trans sucks the big donkey dick, and completely due to the non-synchro first gear. I have one in my 66 Valiant and I hate it. And this is coming form a guy who's spent the last 50 years rowing gears on both a personal and professional basis. I can shift with the best of them, but the A903 first gear is complete crap.

The easy way around this is to get an A230 3-speed and swap it out. It is MUCH stronger, and has all synchro gears.

If we were a year or so down the road, I'd share how I'm going to turn my three-on-the-tree into a four-on-the-tree. It will be theft-proof from any millenial on the planet. :p
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I had a 903 in my 65 Dart. Never an issue. I might have downshifted from 3-2 at times but didn't slip it into 1st until I stopped. I do that with the 833 in my 66 as well. It's a style of driving. Oh, that 903 in my 65 was behind a HP 273. I wish I could have kept that one.
 
JDMopar said:
Here's a 904 transmission and all the kickdown linkage, but shipping may make it a no go, as it's on the other side of the country from you.
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Bingo, even if you can’t make that deal work, someone else will have a pre-‘68 slant six 904 closer to you, and it will usually be very affordable.

If that person is doing a V8 swap, they most likely wont need the driveshaft either. I think you could easily do the whole 904 conversion for under $600 if you are patient, and buy used parts.
 
toolmanmike said:
I had a 903 in my 65 Dart. Never an issue. I might have downshifted from 3-2 at times but didn't slip it into 1st until I stopped. I do that with the 833 in my 66 as well. It's a style of driving. Oh, that 903 in my 65 was behind a HP 273. I wish I could have kept that one.
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Are you sure it was a 903? All the 3 speeds I've seen behind a 273 were the 745 model. Still not ideal, but, stronger than a 903. Every 903 I ever pulled (25-30) needed an input bearing, and all but 2 needed 1st gear too.....and these were all behind a S6.
 

cudamark said:
Are you sure it was a 903? All the 3 speeds I've seen behind a 273 were the 745 model. Still not ideal, but, stronger than a 903. Every 903 I ever pulled (25-30) needed an input bearing, and all but 2 needed 1st gear too.....and these were all behind a S6.
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Heck if I know. I was 16 back in the early 70's and transmission models didn't matter as long as it worked. It was a non synchro 3 speed in a 65.
 
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@biffbaxter what, no photos?!!
 
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