I was at the pull a part today scoping axles. All that really turned my crank were SA/FB rx7 axles. Does anyone know specifics about putting a miata chunk in which axles? Basically, I want a pretty light axle with Limited slip capacity-preferrably cheap. I want a 4X113.4 bolt pattern, but I could accept adapters on this project. I know a GSL-SE axle would be ideal, but those are getting hard to come by. Kinda heavy, too. Goal is eventually horsepower in the high 100's. more like the low 100's to start in a 1700 lb car. any knowledge/suggestions are appreciated.

1 is any FB rear axle that has disk brakes on it already has a clutch type LSD. #2 is all the axles will basically weigh the same, non-SE vs SE. The only real difference with the SE is that the axle flanges are larger in dia, and round, to accomodate the 113.4 bolt pattern. By drilling to replace the stock threaded hole wiIh a wheel stud, you can change the 110 bolt pattern to a 113.4, you just have to make a drill jig to do it with since you will be offsetting the hole by 1.7mm, which is very close to 1/16". I'm pretty sure all 83-85 have the larger rear axles, and spline, which will let you use the 1.8 Miata torsen diff. reply to wheelsmithy:

Miata 7" diff is an exact bolt-in for 1st-gen RX-7. It's the same internals, just that the Miata unit has the attachment points for the power plant frame.

If you start with a '84-85 rearend housing, the axle splines are the same, as well.

The drivetrain page at www.solomiata.com has all the info you could ever want.

superdork to the rescue. thx, knurled