Another 8 3/4 rear question

[Royce Brown]

I have a 1969 Coronet that came with an 8 1/4 rear. My plan is to do a modern hemi swap. I want to upgrade to an 8 3/4. I found one for sale out of a 66 Coronet. According to what I've read in various posts the width for the 66 is 59.5 inches whereas the proper width for my 69 is 60 1/8 inches. I've also read that the spring perches are 44 inches apart in both of these. I'm already planning on having to get a custom length driveshaft and I'm doing a 4 wheel disc brake conversion. From everything I've read it seems like it will work.

Am I missing anything here or am I good to go?

Also, the rear is a pegleg with my ideal gear ratio. Is $200 a fair price for a 66 pegleg 8 3/4?

 

[Jerry Hall]

My opinion yes, easily. You can pay more than that for a peg leg chunk. The chunk would be what I would pay attention to. All 8 3/4's are good but the 741 housing is the least desirable for high performance use.

 

[BeepBeepRR]

489 case would be the one to look for.

 

[tonysrt]

There are 4 different #'s on the rear's, 1820657 up to 64, 2070741 which is small stem, 2070742 which is large stem and the 2881489 which is the larger pinion gear. Sizes are 1 3/8, 1 3/4 and 1 7/8 tapered and this being the best of the rears. All depends on what you're going to do with car and what you can get and afford. I see hemi, so be gentle or go big.

 

[hunt2elk]

489 case would be the one to look for.

Nothing wrong with the 742's either. Just as strong and don't have to mess with the crush sleeve or eliminator.

 

[1967coronet440]

Nothing wrong with the 742's either. Just as strong and don't have to mess with the crush sleeve or eliminator.

Dr diff believes it is the strongest of the 3, check out tech articles on his site

 

[PurpleBeeper]

I have a 1969 Coronet that came with an 8 1/4 rear. My plan is to do a modern hemi swap. I want to upgrade to an 8 3/4. I found one for sale out of a 66 Coronet. According to what I've read in various posts the width for the 66 is 59.5 inches whereas the proper width for my 69 is 60 1/8 inches. I've also read that the spring perches are 44 inches apart in both of these. I'm already planning on having to get a custom length driveshaft and I'm doing a 4 wheel disc brake conversion. From everything I've read it seems like it will work.

Am I missing anything here or am I good to go?

Also, the rear is a pegleg with my ideal gear ratio. Is $200 a fair price for a 66 pegleg 8 3/4?

I think you are absolutely good to go and that is a GREAT price. It will bolt right up & you get 5/8" extra tire clearance. You can find the center section of your choice (posi I suppose) after the rest of the car is done. (and to your purists...sorry to say "posi")

 

[JimKueneman]

Nothing wrong with the 742's either. Just as strong and don't have to mess with the crush sleeve or eliminator.

Nothing wrong with a 741 either other than the limited gear selection.

http://www.doctordiff.com/blog/tech-info/rearend-pinion-comparison/

 

[MoparLeo]

Here is a chart with axle widths, housing widths, spring perch widths.
http://www.moparts.org/Tech/Archive/axle/16.html

 

[Royce Brown]

Ok, it is a 741 case. I still purchased it. I'm building a daily driver and plan to keep the engine very close to stock. Now back to the body work!! Thanks for the info!