318 to 440

[moparmarks]

Ya, you'll need to use the big block transmission since BB and SB are different.

 

[xRickyBobbyx]

Ya, you'll need to use the big block transmission since BB and SB are different.

Make sense. Thanks. I was thinking that.

 

[xRickyBobbyx]

Not sure how much this helps. I'll try to get more info on the engine. If I'm correct pre 72 440s had more horsepower than the latter ones because of the fuel crisis.

 

[xRickyBobbyx]

Finally got my hands on the car. It's a 440, but it's been "hopped" up so I'm told. He's a couple more pics of the engine.

 

[Cranky]

Check to see what rear end is under your 69. Probably an 8.75 but could be an 8.25. The 66 should have an 8.75 which is a little narrower than the 67-70 rear. If yours already has an 8.75 than your good to go.
As Sam stated before, look for the pad on the block.

Yup, the 66 rear will be a bit narrower but not enough to have to worry about moving the springs or the perches.

Ok... so the car originally came with a 361. The 440 was swapped in. It has an 8.75 rear end with 3.23 gears. So that's all perfect. I can swap that over. It's likely my 318 has different gears.

For some reason the teens usually came with 2.94 gears in the rear.....and have you started on the swap yet?

 

[Dave6T4]

1966 (and 1967) rear ends are a couple of inches narrower, but bolt right in. It might allow you run a wider tire back there. Everything else sounds like an easy built-in swap. Your original rearend could also be packing 2.76 gears. Good for you!

 

[Cranky]

1966 (and 1967) rear ends are a couple of inches narrower, but bolt right in. It might allow you run a wider tire back there. Everything else sounds like an easy built-in swap. Your original rearend could also be packing 2.76 gears. Good for you!

The 66-67 rears are a tad narrower but it's less than an inch....think I still have a 66-67 housing that's marked in the rafters and will go look.

 

[moparmarks]

B BODY
'62-'63= 58 1/2" (And '64 Max Wedge)
'64 = 60 7/8" (Exc.Max Wedge)
'65-'67= 59 1/2"
'68-'70= 60 1/8"
'71-'74= 63"
'71-'73 wagon= 64 3/8"

 

[Cranky]

The bare housing I have is 54 1/2" and it came out of a 67 Coronet.....just got to either remember the distance to the axle flange or find a chart. Don't have anymore complete rear ends hanging around to measure. Production tolerances were not all that close on these things and really didn't have to be.

 

[moparmarks]

Here is the complete chart.

Mopar 8 3/4" Rear End Dimensions

........................................
........................................

8 3/4" axle shaft lengths measured from the tip of the splined end
to the outside of the flange:

A BODY
'66-'72= 27 11/16"

B BODY
'65-'67= 28 7/8"
'68-'70= 29 3/16"
'71-'74= 30 5/8"
'71-'73 wagon= 31 21/64"

C BODY
'65-'69= 30"
'70-'71= 30 5/8" (Chrysler & Fury)
'70-'73= 31 21/64" (and '69 wagon)


IMPERIAL (Large Bolt Pattern)
'65-'66= 30 1/8"
'67-'69= 30 5/16"
'70-'71= 29"
'72-'73= 31 7/16"

E BODY
'70-'74= 29 31/32"

A100
'65-'70= 30"

D100
'65-'71= 31 1/8"
'72-'74= 31 21/64

...........................................
...........................................

Housing widths, flange to flange

A BODY
'66-'72= 52 5/8"

B BODY
'62-'63= 53 1/4" (And '64 Max Wedge)
'64 = 55 5/8" (Exc. Max Wedge)
'65-'67= 54 1/4"
'68-'70= 54 15/16"
'71-'74= 57 7/8"
'71-'73 wagon= 59 7/16"

C BODY
'65-'69= 56 3/4"
'70-'71= 57 7/8" (Chrysler & Fury)
'70-'74= 59 7/16" (and '69 wagon)

IMPERIAL
'65-'66= 57"
'67-'69= 57 3/8"
'70-'71= 54 3/4"
'72-'73= 59 5/8"

E BODY
'70-'74= 56 31/64"

A100
'65-'70= 56 3/4"

D100
'65-'71= 58 5/16"
'72-'74= 59 7/16"

.........................................
.........................................

Rear end widths, drum-to-drum:

A BODY
'66-'72= 57 1/8"

B BODY
'62-'63= 58 1/2" (And '64 Max Wedge)
'64 = 60 7/8" (Exc.Max Wedge)
'65-'67= 59 1/2"
'68-'70= 60 1/8"
'71-'74= 63"
'71-'73 wagon= 64 3/8"

C BODY

'65-'69= 61.75"
'70-'71= 63.0" (Chrysler & Fury)
'70-'73= 64 3/8" (and '69 wagon)

IMPERIAL
'65-'66= 61 15/16"
'67-'69= 62 5/16"
'70-'71= 59 3/4"
'72-'73= 64 9/16"

E BODY
'70-'74= 61 5/8"

A100
'65-'70= 61 3/4"

D100
'65-'71= 63 15/16"
'72-'74= 64 3/8"

........................................
........................................
Spring perch widths (center-to-center)

A BODY
'66-73= 43"

B BODY
'62-'70= 44"
'71-'74= 47.3"

C BODY
'65-'73= 46"

E BODY
'70-'74= 46"

 

[xRickyBobbyx]

.....and have you started on the swap yet?

I haven't started the swap yet. I'm bouncing between getting it borescoped, or just going ahead and tearing it down and put it back together. Replace the usual stuff like gaskets and rings. Since it's already built up, I see no need in actually changing anything unless it needs it. That money can go towards other areas that need to be addressed.

 

[xRickyBobbyx]

Thanks for all the info. I definitely want to run as wide a tire as I can without tubs.

 

[Cranky]

I haven't started the swap yet. I'm bouncing between getting it borescoped, or just going ahead and tearing it down and put it back together. Replace the usual stuff like gaskets and rings. Since it's already built up, I see no need in actually changing anything unless it needs it. That money can go towards other areas that need to be addressed.

stroboscope it? Doubt you'll see much other than an axle housing with old oil in it. Pull the axles and 3rd member and look at it with a bright flashlight shining it into the axle tube then look at the 3rd member.

Thanks for all the info. I definitely want to run as wide a tire as I can without tubs.

Using the right offset wheels will allow you to do that with the rear end that's in the car.....

 

[xRickyBobbyx]

stroboscope it? Doubt you'll see much other than an axle housing with old oil in it. Pull the axles and 3rd member and look at it with a bright flashlight shining it into the axle tube then look at the 3rd member.

Using the right offset wheels will allow you to do that with the rear end that's in the car.....

Lol....I should have been clearer. Borescope the engine.

I want to change the rear end because I don't think the one that's in there can handle the extra power. Plus the gearing it's likely different. I'm going it'll give me the best of both worlds. Nice off the line power with decent highway cruising. I honestly haven't tried to take a look to see what is in the 66 yet. Literally almost broke my neck getting it into the garage.