A-833 overdrive options-

[superbirdtom]

i have a 354 factory dana in my bird- i am trying to find a way to get it to be a highway cruiser- i could swap to a 8-3/4 w 323,s but want to know how the passon 18 spline new 4th gear overdrive trannys are? and what the final rpm difference at 80mph in top gear might be. is the gear vendors overdrive a better choice slapped onto a stock 833? thanks!

 

[dodgedifferent2]

I have the passon hemi overdrive a833. I run 4.30 gears and 28" tires so I can't really compare with less gear.
I just finished the install of a t56 and big block but don't have any miles on it as the weather has been crappy.

I played on this site Gives you a better idea.

Speed/Tire/RPM calculator

 

[HawkRod]

i have a 354 factory dana in my bird- i am trying to find a way to get it to be a highway cruiser- i could swap to a 8-3/4 w 323,s but want to know how the passon 18 spline new 4th gear overdrive trannys are? and what the final rpm difference at 80mph in top gear might be. is the gear vendors overdrive a better choice slapped onto a stock 833? thanks!

Welcome to the forum! I suggest you go to the welcome wagon to introduce yourself.

To answer your question:
The Gear Vendors Overdrive is .78:1
The Passon Hemi overdrive is .80:1
So they have essentially the same overdrive ratio. With your 3.54, it will be like having a 2.76 rear (GV) or a 2.83 rear (Passon).

The GV requires transmission tunnel modifications and a shortened driveshaft. This can sometimes lead to some harmonics if you are not careful. On my 73 Road Runner, the tunnel mods were more extensive than they said. The upside is you have at least 5 forward gears. If you split each gear, you end up with an 8 speed. I put my GV behind a 727 automatic, and I found that splitting gears was more of a pain in the arse then it was worth. Perhaps if you drag race it would be, but not in my case. I just left the GV in auto mode, where it switches into OD at 47 MPH.
In the GV case, the weakest link is your existing stock A-833.
The benefit of the Passon OD is that it fits in place of your stock A-833 with zero modifications. It also has a high torque capability so the trans is very stout. The downside is it has only 4 total gears, so it essentially becomes like a 3 speed + overdrive. In my opinion, this is not much of an issue - I'm not sure I "need" 5 or 6 forward speeds in a manual transmission.

I think overall either choice is roughly the same cost.

So which you choose comes down to a bit of personal preference.

Hope this helps

 

[superbirdtom]

well car is already almost put back together so i cant modify anything. Ive been on here for years but not for a couple so i had to reregister. Im looking at the OD one from passon its an 18 spline w the od in fourth - $3650 they also have the 5 speed but its like $7000 brewer told me the OD gears are not very strong for the 4th gear but passon says they have their own made much stronger than ones used in vans trucks etc. the gears them selves. Thanks for the info!!!! Much appreciated

 

[superbirdtom]

I have the passon hemi overdrive a833. I run 4.30 gears and 28" tires so I can't really compare with less gear.
I just finished the install of a t56 and big block but don't have any miles on it as the weather has been crappy.

I played on this site Gives you a better idea.

Speed/Tire/RPM calculator

thanks for the speed calculator that helps me out a lot.

 

[HawkRod]

well car is already almost put back together so i cant modify anything.

I think there is your answer then: Get the Passon Overdrive.

they also have the 5 speed but its like $7000

That is the A-855 transmission. I have one in my Road Runner. It's the best of all worlds, but it is near impossible to get, and as you say, quite expensive. Unless you can wait a long time (I waited 5 years), I suggest the Hemi overdrive.

brewer told me the OD gears are not very strong for the 4th gear but passon says they have their own made much stronger than ones used in vans trucks etc. the gears them selves.

Chrysler made an OD transmission out of the A-833 in the 70's and or 80's (don't remember exactly when). These are weak transmissions and can only handle about 300 lb/ft of torque. I had one in my Road Runner while I was waiting for the A-855. The transmission works well, but you have to be gentle with it if your car has lots of power. Also, the gear spacing, especially between 1st and second, isn't very good.

The Passon built Hemi overdrive is a totally different animal. It is built to Hemi specs and can handle lots of torque. Also, the gear spacing is excellent, so it is much nicer when going from first to second.

 

[Runcharger]

I really like the Passon OD, super clean install and the ratios work.

 

[superbirdtom]

I really like the Passon OD, super clean install and the ratios work.

thank you!!

 

[68-500]

Have you looked at the wide ratio A-833 and a 2.94 rear gear? The ratios all end up very close to the passon 4 spd od with a 3.54/3.91 rear.

 

[YY1]

The main issue I have with my OE 833OD truck trans is LOTS of cross gate 2-3 and 3-2 shifting.

 

[MCODECUDA]

I thought that someone on here or on the A-bodies site had a new Passion OD transmission for sale the other day.

 

[dodgedifferent2]

I thought that someone on here or on the A-bodies site had a new Passion OD transmission for sale the other day.

It was the 855 and it's sold alread

 

[superbirdtom]

Have you looked at the wide ratio A-833 and a 2.94 rear gear? The ratios all end up very close to the passon 4 spd od with a 3.54/3.91 rear.

wide ratio? pls elaborate. also i don't want to change my stock 354. dana. thanks!

 

[superbirdtom]

I think there is your answer then: Get the Passon Overdrive.



That is the A-855 transmission. I have one in my Road Runner. It's the best of all worlds, but it is near impossible to get, and as you say, quite expensive. Unless you can wait a long time (I waited 5 years), I suggest the Hemi overdrive.



Chrysler made an OD transmission out of the A-833 in the 70's and or 80's (don't remember exactly when). These are weak transmissions and can only handle about 300 lb/ft of torque. I had one in my Road Runner while I was waiting for the A-855. The transmission works well, but you have to be gentle with it if your car has lots of power. Also, the gear spacing, especially between 1st and second, isn't very good.

The Passon built Hemi overdrive is a totally different animal. It is built to Hemi specs and can handle lots of torque. Also, the gear spacing is excellent, so it is much nicer when going from first to second.

thanks for that info much appreciated

Welcome to the forum! I suggest you go to the welcome wagon to introduce yourself.

To answer your question:
The Gear Vendors Overdrive is .78:1
The Passon Hemi overdrive is .80:1
So they have essentially the same overdrive ratio. With your 3.54, it will be like having a 2.76 rear (GV) or a 2.83 rear (Passon).

The GV requires transmission tunnel modifications and a shortened driveshaft. This can sometimes lead to some harmonics if you are not careful. On my 73 Road Runner, the tunnel mods were more extensive than they said. The upside is you have at least 5 forward gears. If you split each gear, you end up with an 8 speed. I put my GV behind a 727 automatic, and I found that splitting gears was more of a pain in the arse then it was worth. Perhaps if you drag race it would be, but not in my case. I just left the GV in auto mode, where it switches into OD at 47 MPH.
In the GV case, the weakest link is your existing stock A-833.
The benefit of the Passon OD is that it fits in place of your stock A-833 with zero modifications. It also has a high torque capability so the trans is very stout. The downside is it has only 4 total gears, so it essentially becomes like a 3 speed + overdrive. In my opinion, this is not much of an issue - I'm not sure I "need" 5 or 6 forward speeds in a manual transmission.

I think overall either choice is roughly the same cost.

So which you choose comes down to a bit of personal preference.

Hope this helps

thanks for the info I really want the OD as i want to go to all the great wingcar meets next summer and just want a highway cruiser . no racing or burnouts Too old for any of that. so thanks again for the thorough analysis

 

[68-500]

They won’t lower your cruise rpms final is still 1:1. Youd have to change rear ratio. It was put behind /6 and 318’s had a 3.09:1 first and slightly lower second gear. I wouldn’t know where to find one. Ive been on the lookout for any 4 speed parts for my car.

 

[andrewwoz]

I really like the Passon OD, super clean install and the ratios work.

Curious what gear ratio/tire size you are running? I picked up a 4 spd Passon hemi od trans that I'm planning to swap into my super bee that currently has a 3.55 gear and 28" tires but wondering if I should go to 3.73 or 3.91.

 

[AJReigart]

Curious what gear ratio/tire size you are running? I picked up a 4 spd Passon hemi od trans that I'm planning to swap into my super bee that currently has a 3.55 gear and 28" tires but wondering if I should go to 3.73 or 3.91.

Did you get your Hemi OD trans installed? What rear gears did you select?

I just got one from Passon ..... probably going to 3.91 in my 66 ..... running 28" rear tires also .....