A 833 Transplant: Trunnion Flange to Slip Yoke Conversion

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ConValiant64

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Just getting back into Mopars, so I'm not exactly sure whether I have the flanged output shaft to accommodate a trunnion ball u-joint (specific to 1964 and 1965, I believe) but anticipating this is the case, I need to know what exactly needs to be done to make the conversion to the more popular slip yoke design. FYI-I will be replacing the existing A833 transmission in my 1964 Plymouth Valiant with an A833 from an early 70's Dodge Dart. Will all A-body driveshafts with a slip yoke work? Would the donor driveshaft need to be from a 4-speed car? Little help here...
 
Think you need the bigger yoke and no not all a body shafts will fit. I would measure it and see what it comes out to before I get one. Do a search on driveshafts here there was a great chart around somewhere on them
 
Just getting back into Mopars, so I'm not exactly sure whether I have the flanged output shaft to accommodate a trunnion ball u-joint (specific to 1964 and 1965, I believe) but anticipating this is the case,

If it’s an original 64 833, it should have the B & T flange.

I need to know what exactly needs to be done to make the conversion to the more popular slip yoke design.

Why not use the conversion driveshaft as described in the early Cuda website. It has A female splined part that bolts to the B & T flange with a male matching spine that is added to either your existing driveshaft or a new one.

FYI-I will be replacing the existing A833 transmission in my 1964 Plymouth Valiant with an A833 from an early 70's Dodge Dart.

Why? Something wrong internally or is it the B & T flange that you’re worried about? The 64/65 833 is a very strong transmission with an extra bearing in the tailshaft that later 833s don’t have. They were strong enough to survive behind Max Wedges and Hemi's in 64/65.

Will all A-body driveshafts with a slip yoke work? Would the donor driveshaft need to be from a 4-speed car? Little help here...

No, the length of A Body driveshafts depends on the wheelbase, what rear end is used, and transmission of course. Your 64 has a 106 in wheelbase which is the shortest among A Bodies. I’d say the chances you will have to shorten whatever driveshaft you use will need to be shortened is approaching 100%.
 
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Save the B&T. Conversion is $$$ for nothing gained 'cept maybe the 2.44 first for a closer split than the old "launch even a six" 3.09. Don't know about the rear bearing....Your 833 is max wedge rated.
 
I am looking at doing the conversion to gain the 3.09 in my 69 Dart . I want the low first to bring my rpms up into the cam while tooling around in first.
Question is will the Slipjoint conversion driveshaft be strong enought to launch a solid roller 408 at the strip from time to time ?
If it was going to be run at the strip regularly I would stick with the stock first gear and 68 trany.
 
The conversion looks pretty beefy to me.

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No, I bought it from ragtopfury, who had it made locally in the Baltimore MD area. It was in his son Jake’s 65 Barracuda. They put it up for sale when Jake went in a different direction with the car. It was perfect for me as I am using the identical drivetrain (833 with the B & T flange and 8.75 rear end) as was in Jake’s car. Any decent driveshaft should should be able to make one up.
 
I am looking at doing the conversion to gain the 3.09 in my 69 Dart . I want the low first to bring my rpms up into the cam while tooling around in first.
Question is will the Slipjoint conversion driveshaft be strong enought to launch a solid roller 408 at the strip from time to time ?
If it was going to be run at the strip regularly I would stick with the stock first gear and 68 trany.
I ran the 3.09 for a few years. I really think that it would have been faster with a lower first gear. That 3.09 runs up fast.
 
I ran the 3.09 for a few years. I really think that it would have been faster with a lower first gear. That 3.09 runs up fast.

They would be....
the reasoning behind running 3.09s is to bring my rpms up at very low speeds because of the solid cam profile I am running. I dont want the car bucking while I creep thru a parking lot.
 
They would be....
the reasoning behind running 3.09s is to bring my rpms up at very low speeds because of the solid cam profile I am running. I dont want the car bucking while I creep thru a parking lot.
Hey man, IMO, that's the expensive way to cure bucking.
The real issue is the ignition timing; not that there is anything wrong with whatever you have, but that the pulses are so strong. The key is to soften the pressure hits.And there may be just three ways; reduce the Scr, install a fluid coupling, or retard the timing.
I use a dash-mounted, dial-back, timing box.The box has a range of 15 degrees. I set the timing with the knob near the center. That gives me a range of plus 5/minus 10 degrees. When I go on parade, I just dial the timing back as far as I need to . This is also why my initial timing is just 12 to 14 degrees. With the engine idling at 14 less 10=4*, the timing is so retarded, my 10.9Scr 367 is tame as a pussycat.
To compensate for the meager 14* initial timing, I run a two-stage timing curve that scoots the timing back on track, to 28*@2800. Then I slam the brakes on it with the second spring taking 600 more rpm to reach 32/34 by 3400rpm.
I don't recall the cost of the box, but the distributor springs came out of a smogger 318, which I had laying around.I think I ground a bunch of weight off the flyweights to delay the all-in to 3400.
BTW, this same curve allows me to run 87E10 full-time.
In any case, I already had the E-box, installed for tuning purposes, so I just left it there when I was done.
So for me it was a total of ZERO dollars invested.

Now about that 3.09
It will multiply your idle torque to an additional 16%, complete with plus 16% stronger pressure pulses........ask me how I know..... lol. The only cures for that are; more gear so the jump is used up in less distance, Or, less gear to choke it,or reduce the idle speed, or put a toe on the clutch,Or................. retard the timing. I chose the timing deal.
But,on soft ground, my 367 does not have enough torque at 5* @550 rpm to pull itself, so I have to put some toe on the pedal anyway. Your stroker I bet, will not have that issue,lol.
But why 550rpm? Cuz with 3.55s in the back, this makes 4 mph just possible, which you might know, is a fast walk for a fit person.
Parting shot;
Plus it's really cool to control your idle speed at a red light. My regular idle is 750, and the idle lope of my 230 cam, is hardly noticeable. But when I retard the timing,From the front seat, here it comes!
 
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