A883 4SPD TO A883 OD.

[valkman]

I'm thinking of using an OD I have in place of the 4spd in my Challenger. Anyone done this? Will all the linkage transfer from the 4spd?

 

[Chryco Psycho]

If you are talking about the A833 alum OD I have done many conversions .
There are a # of pitfalls .
The trans is basically a bolt in unit .
The front brg retainer is a unique size @5.12 OD but it is easily cut down to 4.80 so you need a belhousing with a 4.80 hole to fit , the front brg retainer cannot be cut down to 4.35" diameter which is the small belhousing diameter .
Yes the linkage can be used but it is a bit of a challenge as the levers are different on the OD so you may have to swap out levers & for sure adjust lengths to work correctly , the 3-4 front shift rod has to be tweaked as the front shift lever is inverted so shift pattern is correct inside the car , this will cause interference with the crossmember so you will need to bend the rod slightly to clear properly .
The OD accepts the 727/ 833 slip yolk & is the same length so the driveshaft will swap .
The shift unit works well for both but you need to drill holes at the rear of the tailhousing to mount the shifter at the rear .
If you have questions please ask , Glad to help !

 

[Chryco Psycho]

If you are talking about the A833 alum OD I have done many conversions .
There are a # of pitfalls .
The trans is basically a bolt in unit .
The front brg retainer is a unique size @5.12 OD but it is easily cut down to 4.80 so you need a belhousing with a 4.80 hole to fit , the front brg retainer cannot be cut down to 4.35" diameter which is the small belhousing diameter .
Yes the linkage can be used but it is a bit of a challenge as the levers are different on the OD so you may have to swap out levers & for sure adjust lengths to work correctly , the 3-4 front shift rod has to be tweaked as the front shift lever is inverted so shift pattern is correct inside the car , this will cause interference with the crossmember so you will need to bend the rod slightly to clear properly .
The OD accepts the 727/ 833 slip yolk & is the same length so the driveshaft will swap .
The shift unit works well for both but you need to drill holes at the rear of the tailhousing to mount the shifter at the rear .
If you have questions please ask , Glad to help !

 

[valkman]

Awesome thanks, l have a bellhousing for it already

 

[Chryco Psycho]

repeated post

 

[MoparCarGuy]

Expensive but a very good alternative. Gear Vendors Overdrive

 

[valkman]

Expensive but a very good alternative. Gear Vendors Overdrive

Yeah but I already have the OD A883 sitting in garage floor

 

[MoparCarGuy]

Yeah but I already have the OD A883 sitting in garage floor

The OD A883 should work great if your Challenger is a cruiser with a little bit of dragstrip fun.
The OD's 1st gear ratio (3.09) will pull very hard but the 1-2 shift (1.67) will drop you out of the powerband. Not a problem if your primary goal is mileage.

Let us know how your installation turns out.

 

[valkman]

I'm still thinking about it. I have a 3:91 gear (which would make 1st about useless with the OD) and the car really likes it, but she really hums at 70 mph. I had a Barracuda with a 318 3spd, it had a 3.09 1st, and a 3:23 rear which actually run faster in the 8th than when I swapped it with 4spd (had to shift into 3rd with the 4spd)

 

[sportster2000]

I have one in my 73 Challenger. Yes the 3-4 shift plate on the side of the transmission will have to be mounted upside down. I have not done that in my car. The 3-4 shift is backwards in my car. I have learned to live with it for now. It is nice to have because it lowers my rpm at cruising speed. Mine is a steel housing and not an aluminum. It came out of a truck.

 

[Chryco Psycho]

It is not just about milage but the ability to cruise at hwy speeds comfortably .

 

[volunteer]

Lots of variables to consider but I would first ask how 'built' your engine is and what is the idle (900 rpm) vacuum. Me? I would leave the current 833 alone (fresh fluid every couple years) and consider down to 3.23 OR 2.76 in the rear. Too bad 8.75" rears did not offer 2.94 or 3.00 choice.

 

[MoparCarGuy]

Yep. Cruise RPM is more important to me than gas mileage.

 

[SCHU]

FYI , the 2.94 ratio was available in the 8.75 rear in the older 742 case, I have one for sale if anyone needs it. I ran it teamed up with extra wide ratio 833 4 spd gear set , extra low 3.09 1st & lower 2nd gear ( 4th is still direct 1:1 ) , which I also have for sale. Great combo pulls away great feels like a 3.55 & low cruise rpms, best of both worlds . Only reason I removed this set up was to install Passon Perf 855 5-spd, for which I had waited over 7 yrs to finally arrive, with a hefty cost. Please email me with any questions ( [email protected] ) , not on sites much. located Sarnia ON. Canada . thx Doug .

 

[valkman]

Lots of variables to consider but I would first ask how 'built' your engine is and what is the idle (900 rpm) vacuum. Me? I would leave the current 833 alone (fresh fluid every couple years) and consider down to 3.23 OR 2.76 in the rear. Too bad 8.75" rears did not offer 2.94 or 3.00 choice.

I know what you mean, the engine in the car is way I bought the car, an overcammed mostly stock 340, and it had a 2.76 gear and you had to burn the clutch just to get the car moving! This car is just a driver for me and I debated on whether change the cam or change the gearing, and I'm very happy I went the route I did. The 3:91 suits the cam perfectly but does hum at 70+ mph. Gas mileage doesn't concern me that much, but I do like to drive fast on the freeway and the engine drone gets tiring after a while on long drives, not to mention it's working pretty hard.

 

[volunteer]

Lots of variables to consider - - - down to 3.23 OR 2.76 in the rear. Too bad 8.75" rears did not offer 2.94 or 3.00 choice.

Yes, there are earlier 'cases', such as the -741 or -742, however E-bodies came originally with only the -741 (with the straight 1.375" pinion) or the -489" with the tapered 1.875" version. I did suspect that there are indeed 8.75" units (with the small pinion) as OEM with 2.94" gears. Likely - but I have yet to see one.
Would still suggest OEM spec cam - with 'overlap' kept under 50 - degrees. No matter what the compression ratio, keep the vacuum over 12 inches. My '73 has true 10.5 C.R. and I run with 87 octane - so saving lots of $ there. Most of my previous (3.23) E-bodies tached between 25 and 27 hundred at 60 mph - as corrected - depending on tire diameter, but at 70 was more like 3100. Not fun.

 

[Chryco Psycho]

There were also carriers from the 50s using different #s as well for the 8 3/4" .
Cam choice is the most important part of any engine build all parts of the driveline need to be considered to get the best result .

 

[NoCar340]

I re-cased an A833OD gearset into a small-bearing non-OD iron case using the non-floating countershaft... it works with all the factory parts except the 3-4 shift lever and rod. For that, I dug around in a pile of shift levers until I found one with an angle that looked good and modified a 2-3 linkage rod from a 3-speed to work (I bent it). The trans goes right in place of my close-ratio unit, no mucking about with the bell or clutch fork whatsoever, with only a different 3-4 rod. I wanted to be able to swap transmissions easily between road-trip and cruise-night modes. Plus, by eliminating the floating countershaft, the major failure point of the OD trans is gone, especially in the aluminum cases.

If you're going to use an overdrive bell from a truck or F/M-body, call Brewer's Performance and give them the casting number. Your OE fork or pivot probably won't work, nor with the F/M/truck parts. They will get you the right part or parts to make the swap seamless. That's what we did on my friend's '73 Charger 340, using an OD bell and a large-bearing (big block) transmission. There's no downside to the 5.125" bearing retainer other than it only fitting OD bellhousings, so we ran it in place of the original 4.80" part.

Another option is to use an early ('64-early '67) A-body gearset. It's also got a 3.09 first gear, but the same other ratios as the early 2.66 4-speeds. Combined with a 3.23 gear, you'll still get approximately the same launch that an A727 or later (2.47) close-ratio would have with ~4.10s (your cam will still love 1st), but your highway revs would drop dramatically... just not as dramatically as with the OD. This gearset is far from rare or expensive; I found two semi-locally from guys who almost couldn't give away their A-body ball & trunion transmissions. It's easy to ID, too: the 3.09-first close-ratio trans will have a slight semi-circular undercut in the input shaft just forward of the clutch splines.

 

[azmoparboy]

I have the OD 4 speed setup as well in my Challenger with a 11” clutch, and 3:55, limited slip rear. As long as I own this car I will never have it on a race track. The engine tacks 2650 RPM’s around 65 to 70 miles an hour. This is a 383, pretty much stock big block with a 400 horse Fitech efi system on it. It gets about 15/16 MPG, gives me just what I need out it. One other thing l’ve chosen to do is put stock 15” x 7” wheels on the Challenger, that should keep me from tearing anything up on the car.

Just ask yourself what you want to do with your car, then build it. You have many options to choose from. This is the part of the car project I really like, planning and putting it all together.

Good luck,
Steve