Add your abody driveshaft length for quick reference

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Sedanman

Sedanman

67-9 Valiant specialist
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A 108 wb with 904 & 7 1/4 to 8 1/4 swap the difference between 7.25 and 8.25 housings is 1.25 so what ever your original drive shaft measures minus 1.25.

Here is some other tech I've found from here:

108"wb with 440/727/8 3/4=46.5
904/8 3/4=49.25
add 2.25 for 7 1/4
subtract 4" for 727
8 1/4 D shaft is 1.25 shorter than a 7 1/4 D shaft
727/8 1/4 48.9 w/ 108 wb

111" wb w/ 904/8 3/4=51.99

Make sure your yoke isn't tight in the trans & leave about an inch out for play.

feel free to add your set ups so others have a quick reference
 
Im a little confused or just not reading it right but if I have a 904 / 7 1/4 how much shorter does my driceshaft need to be when I ad a 8 3/4 rear thanks
 
if 108 it is 904/8 3/4=49.25 shaft. I just copied what others have done & posted here
 
So 49.25 is what size my shaft needs to be for the 8 3/4 rear how is this measured.. sorry for hijacking the thread that's my last question
 
duster731 said:
Im a little confused or just not reading it right but if I have a 904 / 7 1/4 how much shorter does my driceshaft need to be when I ad a 8 3/4 rear thanks
Click to expand...

As best I can remember you need to shorten your drive shaft 2 1/4" when going from a 7 1/4" rear to an 8 3/4" rear.
 
So, where do you measure from for the drive shaft? Is it end to end, or u-joint center to u-joint center?

Thanks!!
 
My 67 valiant has a 904 & 7 1/4 & c-c of joint is 51 1/4 & I'm swapping in an 8 1/4.
 
ok so not to threadjack but can anyone tell me how long my driveshaft should be for a 318/904 to a 7 1/4 rear for a 73 duster? does anyone know if the splines of a 73 3 speed manual are the same as a 904 in other words would a driveshaft out of a 225/6 3 speed manual 7 1/4 duster physically work with a 318/904 7 1/4 rear end ? thanks, im sure there is a thread on this but i cant seem to find one...
 
My '71 Demon, 360/727/Dana60, 44" cl-cl of 1350 u joints.

Bill S.
 
I have a 66 Dart with 410/904/Dana60 111"wheelbase,measure 52 1/4 center to center.(with 1350 u-joints)When I had the 8 3/4 in the car I was using a stock 73 swinger 318/904/7 1/4 driveshaft(108 wheelbase)worked fine for many races.
 
I am having a good one made so I would like a good measurement. My rearend isnt in yet
 
If I remember right my 4-speed, 8.75 ended up being 49.25, I do have +1 xhd springs and it sits really high in the rear.
Local driveshaft shop it cost me $280 including tax to build one.
I gave them the tranny yoke, they made one with 3.5" tube and 7290 spicer yokes and spicer u-joints installed.

If you are changing from a 7.25 to any rear check the yoke size.
 
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