New Passon A-855 5 sp overdrive

[tommyg29]

As the A855 will not be available for quite a long time I'm asking myself if going to a different rear end gear might be good solution to bypass the waiting time. I guess I'd had to go for 2.84 in that case to achieve similar rpm drop. The drop would apply to each gear however.
Is it difficult/expensive to find an appropriate gear and exchange it? I've never disassembled the rear axle so far.

I think 3.23 is the swap you would consider.

[67vertman]

I think 3.23 is the swap you would consider.

   Unless you plan on doing ALOT of highway driving the 3:23 will give you the best of both worlds. 

[73EStroker]

With my A855, 27" tires and 3.73 gears I get 80mph at 2400-2500. My Passon Hemi OD saw a little higher revs due to 0.8 OD vs 0.7 on the 5 speed. The 3.73s sure get me going off the line nice.

[ShelbyDogg]

I have 2:73 gears with a 4 speed overdrive. Holds at 1750 RPM at 70 mph with a 295-50-15 diameter in back.

The overdrive has a 3.09 1st gear which is good for taking off.  Make sure you have a good 2 plane manifold or EFI if you use my setup. You'll get great gas mpg.

Can't really race anyone on the highway when you put in the 4 speed overdrive so keep that in mind before installing one. You can't downshift to 2nd when going 60 on the highway.
I helped a friend install the 833OD in front of his 4:10 dana, so he now drives the highways.

[IroquoisPliskin]

  Unless you plan on doing ALOT of highway driving the 3:23 will give you the best of both worlds.

We have quite a lot nice highways here in Germany and no speed limit:) Unfortunately the current setup is not really highway compatible. I use 235/60R15 and I have 3600rpm when going 70mph and 4000rpm when going 80mph. With other words high speed is not really possible even on high rpm. And of course higher gas mileage would be nice also.
Any recommendation on rear gear "source"?

...Make sure you have a good 2 plane manifold...

Is Edelbrock Performer RPM ok?

...The overdrive has a 3.09 1st gear which is good for taking off...

How it looks like if I keep the A833 and swap the rear gears from 1:3.55 to 1:2.84 or something like that? Do you expect any difficulties on "take off"?

[73EStroker]

IP, sounds like you want to cruise at low rpm. To do that you want a motor that pulls down  at low rpm. Then if it was me I would have the Passon HEMI OD conversion and run 3.23 gears. The Passon has a 2.65 1st gear so not a dragster off the line. Otherwise I would wait for the Passon 5 speed and leave the rear gears as is!

[IroquoisPliskin]

IP, sounds like you want to cruise at low rpm...

That's true, I'd like to lower the rpm. It's just no fun when you have to spend 2-3 hours on the highway going 80mph at 4000 rpm (always afraid my ears might start bleeding). The plan is to get Passon's A855 and leave 3.55 inside but it is at least one year to wait (I guess it will be longer than that). That's the reason why I'm asking about the rear gear as a temporary solution. I'm just wondering if the car will be usable with the standard A833 and low rear gear or maybe I won't be able to take off at all (or just very very very slowly). I don't care if I can't win a drag race, but the car should move when I push the gas pedal:)

[HP2]

If you consider that slant six cars were available with 2.74 and 2.96 rear end ratios, I'm pretty sure your V8 won't have any trouble betting things rolling.

You also can look at taller tires as an additional way to get the rpm range down.

[IroquoisPliskin]

That's a good hint. Thanks!
The idea with the tires won't work out around here:/
Wheel sizes and types are regulated ridiculously strictly (no one can understand why). Especially the alloys.
I already had a hard time trying to convince the guys to allow me to keep the 235/60R15s. They preferred a swap to 185-195/70R14 or something like that. 

[ShelbyDogg]

Borrow a set of 2:73 gears to try. With the overdrive, I think you will be happy with the 1st. and 2nd gear takeoff speed and the highway rpm too. You'll probably start driving at 80 mph all of the time. When you get your 5 speed, put your 3:55-1 back in. The edelbrock performer is a good dual plane intake.

[IroquoisPliskin]

Sounds good, thanks!
I will need 2.76 ring, pinion and new speedometer gear but how I can make sure if I have a 489 or 274 case?Anything I have to consider because of sure grip?

[ShelbyDogg]

Is there any way to borrow a whole center section to just drop in to try? Open gears will give you the same feel. We Mopar guys always have spares. If your other gears are already setup, leave them alone.

[IroquoisPliskin]

I'm afraid it's not gonna work out to borrow the gears (mopar density too low  ), maybe I could find some to buy. But I think you are right, I guess I will refrain from touching my current gears, especially when I want to go back to that setup when A855 is dropped in. It's too big effort to adjust correctly. I'll watch out for a replacement gears and in worst case everything is gonna stay as it is. 
Thanks for the advice!

[ShelbyDogg]

Put in the 833OD first with the 3:55, you will be happy. I had the OD and my 3:55 behind my fuel injected 440 and averaged over 20 miles per gallon on the HoRod Power Tour.

[IroquoisPliskin]

I think I'll purchase the A855 anyway and in best case I could have it this time next year. If I order an A833OD it will need 3-4 months before I can drop it in. And I'm afraid there will not be a great chance to resell, when I get the A855 (as already mentioned not enough mopars around here).
20 miles per gallon is a dream . My best result is around 12 mpg (but only if I watch out not to accelerate quickly).