8.25" wanted

[Bruceynz]

Hi Guys,

I am in NZ so rear ends are not available here, I would like to swap out my 7.25" to a 8.25", I need to track down a 8.25" that will fit my 1983 Cordoba, if anyone sees or knows where one is can you let me know or help out a fellow J body owner get it, I have a friend in SC and in Seattle who can help me ship to NZ.

Any advice on drive shafts that will fit, a good ratios and if I should worry to much about the ratio. My 7.25" is a 2.2:1 which is a tall gear, its not a racing car so don't need 4.11's or anything like that, I am thinking a 2.45 or 2.7 Anybody's experience and ideas on the subject much appreciated, it I get it wrong it costs me a lot to fix it from half way around the world, so need to get it right the first time.

Many Thanks
Bruce

 

[volaredon]

I know where there is an 8-1/4 with 2.76s (not mine)

 

[Darter6]

2.76 is a favorite of mine for street driving. with speed limits of 65-75 mph around here.

 

[jasperjacko]

I still have the 68,000 mile 8.25 out of Modoba. 2.21 gear. I have a 8.25 3.55 sure grip in her now that I may be swapping to 8.75. The 2.21 is in my garage, but Modoba is in storage until april.

 

[Bruceynz]

volaredon - where abouts and how much?

 

[Bruceynz]

Do you have the drive shaft that is the right length to bolt to the 8.25" and the 904 trans for a J body Cordoba?

 

[jasperjacko]

you talkin' to me?..............Are you talkin' to me?

 

[Bruceynz]

I am no expert with engineering things, if anything I over engineer, isn't that what you do when you don't have an engineering degree to work out loading. Someone suggested to me that if the ratio on my diff went from 2.2 to 3.23 that there would be less load on the diff, I don't know how to compute that in my head or how that relates to the loads on the spider gears, is this possible, is this why some people have no problems?

Thanks
Bruce

 

[greymouser7]

go for 3.21 gears from a 8 1/4 or

3.23 gears from a 8 3/4

 

[greymouser7]

I still have the 68,000 mile 8.25 out of Modoba. 2.21 gear. I have a 8.25 3.55 sure grip in her now that I may be swapping to 8.75. The 2.21 is in my garage, but Modoba is in storage until april.

the 2.25 & 2.45 units do not go in the 2.76, 3.21, 3.55, 3.73, etc. 8 1/4 axles they are different

 

[jasperjacko]

the 2.25 & 2.45 units do not go in the 2.76, 3.21, 3.55, 3.73, etc. 8 1/4 axles they are different

These aren't just the gearsets, but the complete axles.