Manual trans swaps: Cheapest vs Easiest vs Best Performing vs Best Driving Experience

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I’m in the same boat as the OP, I have thought of doing the switch many times, but the cost has held me back. It would be going behind a big block, which makes it a little more expensive, since I can’t find a big block 833 out of an A body anywhere!
Depending on your build, and application, which I am not aware of,
the 1X23 spline input can take a licking.
With street tires and suspension, in stock tubs, I doubt it would be an issue.
 
Depending on your build, and application, which I am not aware of,
the 1X23 spline input can take a licking.
With street tires and suspension, in stock tubs, I doubt it would be an issue.


It's just a street car now, it puts about 375 to the tire, which is a 305, and has super stock springs.
 
I’m in the same boat as the OP, I have thought of doing the switch many times, but the cost has held me back. It would be going behind a big block, which makes it a little more expensive, since I can’t find a big block 833 out of an A body anywhere!

There is no difference in a A body 67-69 4 speed. They are the same small block or big block. Only difference would be if it were 440 or Hemi, 18 spline input shaft and gears.
 
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I’m in the same boat as the OP, I have thought of doing the switch many times, but the cost has held me back. It would be going behind a big block, which makes it a little more expensive, since I can’t find a big block 833 out of an A body anywhere!
Would not a 23 spline work plenty good for most BB engines?
 
I realize all the BB parts can cot more than SB like bells, flywheels etc. I have changed over more than a few but it has got hard for this 72 year old fart to do it anymore. To me, it is worth the work and $ if you can aford it and if you love rowing thru the gears! I love banging gears!!!!!!
 
There is no difference in a A body 67-69 4 speed. They are the same small block or big block. Only difference would be if it were 440 or Hemi, 18 spline input shaft and gears.


I guess I meant in terms of finding one with a BB bell housing already and the correct shifter location for an A body. I know they can all be converted, it's just more money to buy all the parts. It would be nice to find one already setup for that application.
 
The A body A 833 costs a little more than a B or E body but not really very much. Just harder to find. Yes Brewer's has all the needed stuff and they have been into this for many decades now. Good people.
 
There's a guy selling a complete small block a body set up for 2K.. honestly I believe it's a smokin deal.. even worth a pretty long drive.. one of the best parts is it's all clean and ready to install not greasy dirty junk that needs cleaned and repainted...
 
I saw that one and thought it was a great deal with everything is comes with. If I had time for the 20 hour round trip I would probably grab it. Don't have any free time now, work always gets in the way.
 
My 68 Charger started with a 904, then went to a 727, then went to an 833, then a TKO, and now I'm swapping in a T-56 Magnum...

Times are changing for sure - I used to pick up 833s for like $250-$300 *back ~2005-2010 and now I can barely find ANY for sale... when I do they are $750 plus... crazy -

The TKO was a nice trans as I wanted OD - but now I am going to the T-56 so I can run a shorter rear end gear and still cruise nicely.
 
Cheapest vs Easiest vs Best Performing vs Best Driving Experience - which swap fits these categories in your opinion?
One thing worth considering when swapping in a M/T is your minimum driving speed. I don't know if this is important to you, but it was to me, for parading purposes, and inching along in traffic.
With a M/T you don't have a fluid coupling, so the engine, in gear, is married to the tires. If your engine won't idle, and pull, below 750, then it will require a pretty big rear gear to get down to walking speed.
For example, say you had 3.23s to keep the Rs down at freeway speeds. Then, your minimum speed might be ;
(rpm x tire diam. x pi)/(1056 x R1 x R2)=mph
Where the Rs are your low and rear gears.
pi is 3.1416
So, with a standard A833, and 27s;
750x85/1056 x 2.66 x 3.23=7.03mph.
If your cam is running near the bigger end of what's recommended for street, then loaded at this mph, it is already starting to get jumpy. By 650rpm/6.1mph, you will be well into the bucking.
There are only a few things that I know of, that can alleviate this bucking;
1) a lower first gear
2) less idle-timing/ less cylinder pressure
3) a lower rear gear
4) slipping the clutch

As to #1
If you don't already have a trans, then your first option is to get one with a lower first gear, like the Commando box with it's 3.09 low gear. This gets your starter gear down to; 3.09x3.23=9.98/6.05 mph @750 rpm
As to #2
less cylinder pressure, can be achieved by; A) a lower compression ratio, B) a later closing intake,or C) retarded idle-timing.
A) is counter productive to every reason for making power, bad choice
B) comes with a longer overlap period, increasing the engine's operating rpm, and consequently reducing it's minimum operating rpm, bad choice
C) is the only one to consider. By retarding the idle-timing, peak cylinder pressure is reduced, AND more importantly, it comes later in the cycle when the piston is already well on it's way down the cylinder. So the bucking sorta gets lost in the ever growing space created by the falling piston. The penalty is a huge reduction in idle-power.
But now, if you reduce your idle speed by electronically manipulating the idle-timing,(see note #1) leaving the transfer slot exposure alone, then perhaps you can get your in-gear idle speed down to 550rpm, and now your minimum roadspeed is; 550x85/1056x3.09x3.23=4.44mph, still higher than walking speed.
As to #3
To get to walking speed,about 3.5 mph, your last option is the rear gear, and requires a new rear gear of 3.23x (4.44/3.5)= 4.10s for
550x85/1056x3.09x4.10=3.49mph
This indicates a starter gear of 3.09x4.10=12.67, and the engine doesn't care how you get it. It could be as above;
3.09low x4.10rear, or it could be
3.24low x3.91rear,or
3.40low x3.73rear,or
3.57low x3.55rear,or even
2.66low x4.76rear
So now, for a streeter, the low gear becomes really important, as Mopars only have these three available;3.09,2.66,2.47. I think the T-56 is available in 3.49 and or near 4.xx, but not sure at all.

OR
if the next smaller cam idles down to 500, then
500 x 85/1056x3.09x3.55s=3.67mph;
OR
if you buy a fast-rate of lift cam with short clearance ramps, then the bucking starts at a slightly slower rpm in the first place; (see note2)
As to #4
this is not really a long term solution. But in a pinch......... you know; following pom-pom waving Barbie, daymn the clutch.


note #1;
As to the electronic timing device, my combo gets down to 500/550 @5* idle-timing, with a 230*@.050 cam.
I'm not really a fan of idling that low, but I did several mods inside my engine to encourage it's survival. It seems to be working,since the changes were done in 2004 or 5. To get my idle-timing down to 5* from 14*; I use an in-cab,dial-back, timing retard device, that I originally bought for tuning the power-timing. It has a range of 15 degrees, that I can set anyway I want. I set mine to;
9* retard/ 6* advance. The 6* advance comes in handy when the engine is cold cuz 14+6=20, and the engine warms up nicely on that without a choke.
Note #2
So, IMO, this is another great reason to chose one of those fast rate-of-lift cams. It's been said that this type of cam has a shorter lifespan, but IDK. My Hughes HE 3038AL was new in 2004, and the ramps on it are advertised at 276 less 230=46*; not particularly fast. But I installed the 1129 Dual-springs on it and shimmed them up enough to where the engine spins 7200 pretty regularly. So it's no slouch. That cam has over 60,000 miles on it, and I wish the slugger would die already, cuz I wanna try a solid.......... they have faster ramps,lol.
Note #3
As you can see, covering all the bases with a 4-speed takes some pretty interesting ideas. Ideas that a 5-speed instantly does away with. With a 5 (or more) you can run pretty much any gear you want to.
As a side note;
my combo (see my sig) will idle down to 500/550 in gear,with an ancient 750DP. That is in 3.09x3.55 low gear. But it has zero extra power. The parking lot has to be pretty much flat, and level, and hard. The slightest incline, and she starts dropping Rs. I compensate by adding timing up the hill and then subtracting it when the Rs begin to climb. But I have to be alert to watch for the bucking, and if it starts, then I have to put some slip in the clutch. My cylinder pressure is a tic under 180,and the Scr is just a tic under 11/1;so Ima thinking that has something to do with it too.
You cannot do this with speed-screw adjustments, which screw up the transfer fuel delivery, and then the engine just stalls. You have to do it with timing...... just like your outboard boat motor does. On the smaller 2-cycle engines, the first 1/4 throttle ,or more, is just advancing the timing.
 
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I include the math so folks can follow along as to how I get from point A to point B. I realize it clutters up the posts, but I feel it's important; perhaps not to OP, but perhaps for someone in the future, hitting the search button.
 
I fail to comprehend your statement.
Well, say you had a Mopar 4-gear, and 3.55s; and used 1.92 second gear for 3.5 mph; your engine rpm would be.......296. I can't think of any stock Mopar V8 that would run there, never mind a cammed up one.
So; I fail to comprehend your statement.
 
You got me, I was thinking the other way around, a deeper gear, not a shorter gear. Been a rough couple weeks cooped up in the house.
 
Does anyone have direct experience putting a TKO 5 speed into an a-body with a factory bench seat?

From their installation manual, it looks close, too close to call from a pic, and I'm no giant so putting the seat back in another zip code isn't an option. Plus, I have rear seat passengers at times and I don't want their kneecaps to be my lumbar support.
 
It would be really hard for me to use an 833 in any modern build-up unless I was using it in an original 4 speed car and wanted to stay close to stock etc.

The 833 was a great gearbox. It still is. But it's also heavy and....not-the-smoothest-shifting. Far from it. It also doesn't have an overdrive, or if it does it has only 3 non-OD gears.

I have no experience with Passon and the like but certainly there are other threads on this BB worth reading.

If I had my choice of a street driven manual gearbox, I'd use a TR-6060 out of a Hellcat (not any other version due to gear ratios). It's heavy and not the best shifting, either, but it handles lots of power and has two OD's that are 'intelligently' geared.

For a race gearbox, I'd look into a Liberty or G-Force or one of the other boxes that shift fast and are super light.

Of course, the mighty green Valiant's transmission offers the best in terms of high RPM clutch dropping and manual gear changes but will also gladly change gears automatically should you fear a missed shift or get caught in traffic or wish to have Granny run to the stores for smokes and vodka.

aaLH.jpg
 
No such thing as cheap. you have options. the math shows it! depends what you want.
i have coplete 4 speed swap A body ODtrans new clutch etc..
whats easiest is a donor swap car.
just depends what you want!
 
Like the 90/10 rule, this also is true: If it is good, it is not cheap, and if it is cheap, it is not generally good!

There are many other old folks rules, that all make sense, too. Lots of them about women ,money, dogs and horses.
 
One thing worth considering when swapping in a M/T is your minimum driving speed. I don't know if this is important to you, but it was to me, for parading purposes, and inching along in traffic.
With a M/T you don't have a fluid coupling, so the engine, in gear, is married to the tires. If your engine won't idle, and pull, below 750, then it will require a pretty big rear gear to get down to walking speed.
For example, say you had 3.23s to keep the Rs down at freeway speeds. Then, your minimum speed might be ;
(rpm x tire diam. x pi)/(1056 x R1 x R2)=mph
Where the Rs are your low and rear gears.
pi is 3.1416
So, with a standard A833, and 27s;
750x85/1056 x 2.66 x 3.23=7.03mph.
If your cam is running near the bigger end of what's recommended for street, then loaded at this mph, it is already starting to get jumpy. By 650rpm/6.1mph, you will be well into the bucking.
There are only a few things that I know of, that can alleviate this bucking;
1) a lower first gear
2) less idle-timing/ less cylinder pressure
3) a lower rear gear
4) slipping the clutch

As to #1
If you don't already have a trans, then your first option is to get one with a lower first gear, like the Commando box with it's 3.09 low gear. This gets your starter gear down to; 3.09x3.23=9.98/6.05 mph @750 rpm
As to #2
less cylinder pressure, can be achieved by; A) a lower compression ratio, B) a later closing intake,or C) retarded idle-timing.
A) is counter productive to every reason for making power, bad choice
B) comes with a longer overlap period, increasing the engine's operating rpm, and consequently reducing it's minimum operating rpm, bad choice
C) is the only one to consider. By retarding the idle-timing, peak cylinder pressure is reduced, AND more importantly, it comes later in the cycle when the piston is already well on it's way down the cylinder. So the bucking sorta gets lost in the ever growing space created by the falling piston. The penalty is a huge reduction in idle-power.
But now, if you reduce your idle speed by electronically manipulating the idle-timing,(see note #1) leaving the transfer slot exposure alone, then perhaps you can get your in-gear idle speed down to 550rpm, and now your minimum roadspeed is; 550x85/1056x3.09x3.23=4.44mph, still higher than walking speed.
As to #3
To get to walking speed,about 3.5 mph, your last option is the rear gear, and requires a new rear gear of 3.23x (4.44/3.5)= 4.10s for
550x85/1056x3.09x4.10=3.49mph
This indicates a starter gear of 3.09x4.10=12.67, and the engine doesn't care how you get it. It could be as above;
3.09low x4.10rear, or it could be
3.24low x3.91rear,or
3.40low x3.73rear,or
3.57low x3.55rear,or even
2.66low x4.76rear
So now, for a streeter, the low gear becomes really important, as Mopars only have these three available;3.09,2.66,2.47. I think the T-56 is available in 3.49 and or near 4.xx, but not sure at all.

OR
if the next smaller cam idles down to 500, then
500 x 85/1056x3.09x3.55s=3.67mph;
OR
if you buy a fast-rate of lift cam with short clearance ramps, then the bucking starts at a slightly slower rpm in the first place; (see note2)
As to #4
this is not really a long term solution. But in a pinch......... you know; following pom-pom waving Barbie, daymn the clutch.


note #1;
As to the electronic timing device, my combo gets down to 500/550 @5* idle-timing, with a 230*@.050 cam.
I'm not really a fan of idling that low, but I did several mods inside my engine to encourage it's survival. It seems to be working,since the changes were done in 2004 or 5. To get my idle-timing down to 5* from 14*; I use an in-cab,dial-back, timing retard device, that I originally bought for tuning the power-timing. It has a range of 15 degrees, that I can set anyway I want. I set mine to;
9* retard/ 6* advance. The 6* advance comes in handy when the engine is cold cuz 14+6=20, and the engine warms up nicely on that without a choke.
Note #2
So, IMO, this is another great reason to chose one of those fast rate-of-lift cams. It's been said that this type of cam has a shorter lifespan, but IDK. My Hughes HE 3038AL was new in 2004, and the ramps on it are advertised at 276 less 230=46*; not particularly fast. But I installed the 1129 Dual-springs on it and shimmed them up enough to where the engine spins 7200 pretty regularly. So it's no slouch. That cam has over 60,000 miles on it, and I wish the slugger would die already, cuz I wanna try a solid.......... they have faster ramps,lol.
Note #3
As you can see, covering all the bases with a 4-speed takes some pretty interesting ideas. Ideas that a 5-speed instantly does away with. With a 5 (or more) you can run pretty much any gear you want to.
As a side note;
my combo (see my sig) will idle down to 500/550 in gear,with an ancient 750DP. That is in 3.09x3.55 low gear. But it has zero extra power. The parking lot has to be pretty much flat, and level, and hard. The slightest incline, and she starts dropping Rs. I compensate by adding timing up the hill and then subtracting it when the Rs begin to climb. But I have to be alert to watch for the bucking, and if it starts, then I have to put some slip in the clutch. My cylinder pressure is a tic under 180,and the Scr is just a tic under 11/1;so Ima thinking that has something to do with it too.
You cannot do this with speed-screw adjustments, which screw up the transfer fuel delivery, and then the engine just stalls. You have to do it with timing...... just like your outboard boat motor does. On the smaller 2-cycle engines, the first 1/4 throttle ,or more, is just advancing the timing.


AJ, I didn’t read all of this post, or the first one, but did you include rotational inertia of the flywheel in your calculations? A 30 pound flywheel covers a multitude of errors.

Also, if a stick car is bucking at low speeds, that is 100% carb tune up. No cam should ever do that. It’s a carb tuning issue.
 
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