I have a quick question concerning the date at which Mazda switched from small axle to large axle? My car ('83 GS) shows a production date (on the drivers door) of 9/83. Would this be considered a "later" model '83? If so, can I be positive that I have large axles?
Obviously it has drum brakes, but lately I've been considering just swapping the pumpkin and either getting a higher gear ratio or LSD (or both...KIA?).
Any recommendation....I'm not convinced that I need to swap-out the entire rear end...my opinion is the drums are sufficient for my needs, but I DO want the LSD. I'm still in the "thinking it over" stage, so I'm open to suggestion.
Thanks

 

I do not believe that is late enough to be big spline axles but you will not know for sure until you measure something.

Some older post I made and found through the search function.

 

My 7/83 has small axles.

 

'83 models use the 84/85 driveshaft, but use the small axles.

'84-'85 models use the large axles

Parts fiche does not list a mid-year VIN split for the change, so you will only have large axles if you have an '84 model.

'84 models started being built in 9/83. The serial number portion of your VIN should be 800001+ to be an '84 model.

 

exactly.

 

so according to this, if i were to have a small axle housing laying around i couldnt use it to make a big axle one if i had spare axles lying around?

 

There is no bearing solution to use big axles in a small axle housing. For what its worth the whole mid year 83 size change is BS, all 83s had the large driveshaft flange and small axles. Where the confusion stems from is some of the 84 cars were made in late 83, but were sold as 84s. Mr john doe rx7 owner says "my car has an 83 build date but big axles...OMG ONOES!" without thinking for a second and realizing his car is an 84.


Isaac

 

either that or they look at the big driveshaft flange...

 

Brining this back up sorry, so If I wanna get a rear end out of a 83 with LSD and put it in my small bearing car do I need to change the driveshaft flange or is that even possible? Im looking to put it in a RX2.

 

That's weird, new model year production generally started in August.

I could have sworn that my '84 has an 8/83 build date.

 

I have small axles, (83 LSD Disc rear end in my 85 car) and have had no problem with it at all whatsoever.
BUT, instead of swapping gears, I put a 87-88 NT trans in, (much higher ratios)
If you want lower gears, swap gears.
As far as LSD, I've never actually driven a car without a LSD, so, I can't say it works wonders but just from purely understanding what it does, I'd say it's a must.

 

In an rx7 you would just use the 83-85 driveshaft, but I do not know if the length is the same for an rx2. If you remove the flange you will need to replace the crush tube, and re-set lash.


Isaac