71/4 rear end

[snakesden73]

hi ill be asking alot of questions im rebuilding a 73 charger its my first time tring this i would like to know if i could swap the 7 1/4 rear end with a 8 1/4 without doing any modifications

[Nacho-RT74]

as far we have discussed, just the driveshaft lenght could it be diff ( if you take the axle from 73/74 B body )

that's a fact changing to 8 3/4, dunno is that's a fact on 7 1/4 to 8 1/4

[bordin34/Dan]

Your car should already have an 8 1/4 on it unless it was switched at some point.

[DynoDave]

I'd have never guessed that there was a 7.25 rear for Chargers, not even for slant 6 ones.

[Nacho-RT74]

I don't think either, but with MaMopar never knows, specially since 73

[brock]

Is there a list or link to the normal rearend size/type/ratio for 71 to 74 Chargers based on engine
& tranny combos? My 72 SE is not an 8.75" 400 2bbl auto should be what rear? Any
idea what the default ratio would be with this combo & A/C?

[DynoDave]

Brock,

A peak at your diff. cover should help you ID it using this chart. If it's not an 8.75, it's bound to be an 8.25 or 9.25. 7.25 and a big block is not an option.



I'm interested to see what you come back with....I didn't think they started putting 8.25s behing big blocks until the mid/late 70s, when HP was really down. My '77 Cordoba has an 8.25 behind a 400/4, but by then the 400/4 was only making 190 hp.

[bordin34/Dan]

my 73 400-2 has an 8 1/4 and i bet 99% of all the 73/74 auto 400-2 had them. My 74 318 had an 8 1/4 also.

[DynoDave]

Thanks Dan. I guess I grew up thinking that if you had a /6, you had a 7.25, a 318/360 and 8.25, a 340 or big block an 8.75 or 9.25 (or Dana). But that's just the way it worked. As I said, I knew later Bs got the 8.25 behind the big blocks, but I had no idea they had done that to early 70s Bs.

[brock]

Thanks for the chart Dave. Yep, mine's a 8.25

I'll want to change that to an 8.75 for sure