Good bye highway gears. Hello 3.55

[70ChargerRT]

, I have a 4.10 Dana 60 in my 70 Charger R/T SE, it's a 4 speed car too. I will be going with some kind of overdrive transmission. I am leaning towards the A855 5 speed transmission. The car will have a 472 dual quad Fitech fuel injected Hemi in it.

I probably wouldn’t want to cut the floor up on that original 4-speed car either but I have no regret doing so on my car. My Close ratio T-56 Magnum is awesome. If I ever blow this engine up I’ll probably do a Ray Barton Efi Hemi of some sorts.

 

[70ChargerRT]

There’s no sense in being scared! I’ve got my rev limiter set at 6k RPM. The highest I ever hit it was at 5800. So im
Not for sure what my RPM was at.

 

[chargervert]

I was so happy to find out my plymouth I got from Dave had a 3.55 SG!!!

That is such a nice car you got.

 

[TorRed]

4.10 with GearVendors is magic

Good to hear, I have the parts to put both in my Bird.

 

[chargervert]

Yesterday afternoon my much awaited delivery arrived from Strange Engineering! A big heavy, beautiful 3.54 Dana 60 year axle for the 71 Charger R/T!

 

[70ChargerRT]

Yesterday afternoon my much awaited delivery arrived from Strange Engineering! A big heavy, beautiful 3.54 Dana 60 year axle for the 71 Charger R/T!

View attachment 1666826

What was turnaround time?

 

[JC Boatguy]

That is such a nice car you got.

View attachment 1665920

That is such a nice car you got.

View attachment 1665920

thank you, it is quite special, updated pic

 

[chargervert]

What was turnaround time?

Six weeks.

 

[chargervert]

Primed,painted and installed in the car.

 

[Black_Sheep]

I think 3.55’s are a good all-around gear ratio for a weekend cruiser. I have a 3.55 Sure Grip in my ‘58 Apache, acceleration is decent and I’m not afraid to jump on the highway and keep up with the flow of traffic.

 

[Coelacanth]

I like the 3.55/3.54 gear sets. A 3.73 used to be my favorite but now that I have 2 Plymouths with 3.55/3.54, it’s my new favorite

I'm interested to hear your observations on 3.73 vs 3.55. I am so torn between the two choices. My '70 Charger has a mildly built 383 Magnum and 3.23 gears. I want a stronger kick in the pants without going crazy high RPM's on the infrequent highway drives I'll be doing. I was running a 27" diameter wheel & tire with the 3.23, now I'll be running a 28" combo with whatever ring & pinion I go with. Part of me wants the 3.73 because upsizing my tire from 27" to 28" and only going from 3.23 to 3.55 might not make much noticeable difference with the tire diameter upsize. The place offering the aftermarket gears said I should go with 3.73's. Looking forward to your impressions.

 

[Kern Dog]

I think that the 383 needs a deeper gray just to get rolling.
The 383 has a stroke barely longer than a 318 or 340 so it needs mechanical leverage to make power.
The 383 in Jigsaw is a 9.2 to 1 mill with mildly ported heads and a MP 280/474 cam. With a 3.23, it felt slower than my 72 Duster with a stock 360. I switched to a 3.91 gear and it is much better.

 

[Coelacanth]

Thanks KD, what are your impressions on the highway, RPM-wise?

 

[Kern Dog]

I don’t drive it for extended periods on the freeway. I don’t recall the rpms I was turning. It is much more snappy though with the deep gears.
I did have a 4.10 gear in the other car and 3800 rpms at 65-70 is really annoying.