Opinions on 4 speed with OD
- Thread starter Steve welder
- Start date
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Josh owen
Bang em till it breaks
I've got 3.23s in my 67 and it runs 2500rpm and 60mph with a 340. My 71 duster im building has the cast iron OD box going in with 3.91 sure gripand I also have a 3.55 full spool center I can swap back and forth and also another 340 car Im mixed now on weather to run the od or standard non od....
Steve welder
Well-Known Member
Yes and thanks for reminding me....I was going to replace the throw out bearing anyway but my clutch and pressure plate is new
I will ask about the conversion kit and if he can install in my trans
Im going to call today and will absolutely get back to you
Thanks again
DionR
Well-Known Member
Curious what makes you favor the OD over the Tremecs? Difficulty of install not worth the extra gear? Something else?
In my case, it is a true 340 4 speed car, I have no interest in butchering the floor. I would absolutely do it to a non performance model car, the driveability and utility of the Tremec would be awesome.
Tremecs weren't the greatest shifting. Notchy and weren't able to power shift without grinding or not going into gear at all. I had the first one in a Duster in 2000 then 2002 in a B body. I did have to do some surgery to install them,not much just had to remove a few bosses in the case to clear the floor.Now things may be different 20+ years later.Both cars I had to have driveshafts made but can't remember if I had too or if I wanted too.
Nothing against Brewer's I never dealt with them. Jamie Passon I have known and dealt with for over 20 years.
Nothing against Brewer's I never dealt with them. Jamie Passon I have known and dealt with for over 20 years.
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DionR
Well-Known Member
My car is a real 360 4 speed car and I have for years waffled over putting a modern trans in it because I didn't want to cut the floor. In the end, it comes down to driving enjoyment and not cutting the floor is pointless if I'm not going to sell the car. So I am going T56/TR6060.
I appreciate your viewpoint, it is likely the right answer, I cant get my head there though.
DionR
Well-Known Member
The new TKX is supposed to be the bomb compared to the old TKO's like you had. And the old TKO swaps usually had a bad driveshaft angle that could cause problems too.
I can see your point though, if you are getting on it and the trans won't shift, makes it hard to overcome the value of the extra gear.
I still look at pictures of your Duster. Sweet car. Too bad the trans detracted from the overall build.
DionR
Well-Known Member
I completely understand.
Honestly, if I still had my Challenger it wouldn't probably be something I would do.
trapster
Well-Known Member
I have a 340 with a iron 833od gearbox 3.55 LS 8 3/4 and 14 inch tires. And I hate it. first gear is too low second gear is too far from first and 4th gear is noisy. I am planning to swap back in a non OD 833, and maybe add a gear vender unit. The 833od were designed to be for fuel efficiency behind slant six's and not for "fun".
Thanks for this response, these are exactly the concerns I, and likely others, had feared.
You’d like it a lot better with taller tires.
Just sayin…
Just sayin…
dodgedifferent2
Well-Known Member
I run the Passon hemi overdrive.
4.30
28" tire
340 stroker (418)
I received a gear set early this year because of my stupidity but that is a whole other story.
I did not have any issues with Jamie Passon he was very helpful. I did have to wait awhile because of covid shutdowns :-(
I have been working on a big block stroker combo and picked up a tr6060 from an 11 challenger and converted it to a t56 magnum. OD drops to .50 Doing some digging I would be same rpm area as the 11 challenger if I run 28" tire and 4.10 gears.
Would I do the passon hemi OD again? It has its place and I have no complaints with it. Bolt in and drive (18 spline input)
Why the t56?
I have a habit of looking at things and wanting the challenge. Big block and double overdrive and possibly some fuel economy sucked me in. Likely rarely use the 6th gear but I could blast down the highway at 100mph at 2500 rpm with 4.10 gears
Here is an rpm calculator that I have played with over the years.
Speed/Tire/RPM calculator
4.30
28" tire
340 stroker (418)
I received a gear set early this year because of my stupidity but that is a whole other story.
I did not have any issues with Jamie Passon he was very helpful. I did have to wait awhile because of covid shutdowns :-(
I have been working on a big block stroker combo and picked up a tr6060 from an 11 challenger and converted it to a t56 magnum. OD drops to .50 Doing some digging I would be same rpm area as the 11 challenger if I run 28" tire and 4.10 gears.
Would I do the passon hemi OD again? It has its place and I have no complaints with it. Bolt in and drive (18 spline input)
Why the t56?
I have a habit of looking at things and wanting the challenge. Big block and double overdrive and possibly some fuel economy sucked me in. Likely rarely use the 6th gear but I could blast down the highway at 100mph at 2500 rpm with 4.10 gears
Here is an rpm calculator that I have played with over the years.
Speed/Tire/RPM calculator
DionR
Well-Known Member
I used 6th in my Challenger every single day. And my calc's say with my 25.7" tire and 3.55 gears I will be running virtually the same RPM's across the board (your results may vary), and with a 5.7 Hemi it should pretty much run the same.
But, everywhere I go I have to spend 30 minutes or more at 60+ mph which greatly influences my desire for a good OD trans. If I was someplace where most of my driving was on city streets, I doubt I would care or even want OD.
gzig5
Well-Known Member
I had a 833OD in my '77 Aspen RT from the factory. I had no issues with that transmission. The 318 was fairly weak, but that thing would cruise for days and was still sporty off the line. I always thought that a stout small block or stroker in front of it with 400+lb-ft of torque would take care of the big 1-2 split. I doubt the OD design is any louder than a regular one and that is up to individual condition. I currently have one of each regular and OD to put in my Cuda. I'm starting with the standard, but with the amount of driving I plan on doing I foresee and OD of some sort in my future. I'll give the 833OD a try before I drop $3000-$5000 on a Gear Vendoer or TKX
DionR
Well-Known Member
Mine seems to, and I don't have 400+ lb/ft of torque.
Steve welder
Well-Known Member
I haven't called passion yet but they advertise the transmission at $3,600. No shipping as I will pick it up
What im hoping is he will offer me something for my 23 spline rebuilt 833
The Tremec while im not ruling that out is 5 grand plus another 300 for shipping, so im looking at around 1700 savings plus no modifications to car
I can do any modifications and the Tremec is a heck of a lot lighter than the 833 so that helps
I really have to talk to Passion later
Will let you know soon as I find out
Thanks for advice
AJ/FormS
68 Formua-S fastback clone 367/A833/GVod/3.55s
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Ok then;
About the biggest tire you can put on an A, without modifications, is about 27.5"
the smallest 14" that anyone is likely to install is 24.5..
That is a range of 27.5/24.5=about 12%, which is about ONE gear-change; say from 3.73s to 4.10s. Therefore, I did not say that OP had 3.91s, but merely said
"points to".
However;
IDK anyone who installs 24.5s on the back of a muscle/pony/classic/whatever, car, nor do I know of any 27.5" street-tires. Therefore, a tire in the range of 26 to 27 inches is a pretty safe bet to use in a thread like this.
Furthermore Op clearly stated, not in so many words, that the tach-reading might be a little iffy.
Therefore, some assumptions HAVE to be made. For instance; since OP did not mention the rear gear ratio, I assumed that he did not know it. Why waste a post to ask him? Why waste his time making him go out and figure it out? Math is just way easier.
OP said;
AND the title of the thread is;
Therefore, since I have thoughts,Plus opinions ..... Plus experience, I gave them; Furthermore;
I even introduced my post by specifying;
See; that is a thought and/or an opinion.
It was not I who asked YOU for your thoughts, as to what I should or should not post,
nor was it I who asked for your opinion as to my experience.
Post your own experience, and let OP figure it out.
But since you asked; and I assume that you're not too good at math, or are just lazy, or vindictive, grumpy, or just not getting any;
For 50mph = 2500 +/-200rpm, and tires ranging from 24.5 to 27.5; all the possible rear gears are from ~3.35 to ~4.50 ..................
Obviously some assumptions had to be made.
Up the middle is this;
50= the average,2500 x the average of 24.5 to 27.5, x pi(3.1416);
divided by 1056 x 50 =3.8675,
in Mopar-ese, this rounds to,
wait for it.......
3.91s
You're welcome
.
@AJ/FormS
28 inch tires fit. Larger of you roll the lip. “assumptions”, key word, often a mistake, this is why it’s not wasting a post since better information cuts down on your long winded posts that don’t help as well as you think they do.
And the mighty Bible thumper has failed again !!!!
Tell us (really lie) again how you get 38 mpg’s from your 7,000 shift point 360.
28 inch tires fit. Larger of you roll the lip. “assumptions”, key word, often a mistake, this is why it’s not wasting a post since better information cuts down on your long winded posts that don’t help as well as you think they do.
And the mighty Bible thumper has failed again !!!!
You should get your head out of your *** & out of the calculators and actually do some wrenching.
Tell us (really lie) again how you get 38 mpg’s from your 7,000 shift point 360.
autoxcuda
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What do you think of the gear spread with the Passon OD gear set? Compared to a stock gear set?
I know someone that had one behind a 472 Hemi and didn't like the spread. His opinion.
dodgedifferent2
Well-Known Member
Compared to a stock a833 there is not much difference between 1 and 2. Enough rpm cancels everything out.
In town driving (30 mph) I hover between second and third. Almost like another gear needs to be there, but I assume the camshaft had a part in that.
I do a big portion on the highway 55-60mph.
I don't have much seat time with the stock 4 speed gear set and never played with the stock OD gear set.
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