Need a new rear end setup
 

I'm in need of advice. I joined about a month ago and said I bought a V8 Miata with a carburated 302, T5, and a solid 8.8 axle. Well, the shock mount gave way on the axle and the welds are not looking so hot. I knew it coming into this I would need a new rear end, but I was hoping to do it a year from now.

What all this means is I really hurting on money, I have no rear sub frame or control arms to work with and I need a whole new setup to bolt in. Any idea what I should expect from a salvage yard for a full sub-frame with brakes an hub (no diff)?

What kits from what sites and what differentials should I be looking into? I'm guessing a Ford 7.5 out of a T-Bird is the cheapest option, but I think the LSD 7.5 in those are hard to find and are clutch based, no? And I beleive the Boss Frog is the cheapest route to go, but is it any good and how hard is it to install? I'm just a "driveway" mechanic. I can do oil changes, ball joints, brakes, etc, but I have more experienced people that will help me. Does this kit require any welding?

Thanks in advance for the help!

I am not sure if you got anywhere on this but I would be interested to know what your solid rear axle setup looks like. I am currently running a RX7 II clutch style lsd and it works great it bolts into the stock miata cross member and if you use 01 miata axles they pop right in no modification needed. These have seen 400whp and are still holding up but I am not sure for how long. If you have not removed your solid axle yet could you possibly send me or post some pictures of it I am been looking into doing a solid axle swap to my car. I have had no issues with my rear end setup but I plan to push the car to over 500whp so I may run into issues then.

sent you a PM

The Boss Frog kit is a bolt in as long as you use a 94 up subframe. It has the tabs for the lower plate built in. Check the forums and see what you can find. Folks part out cars on a regular basis.
The IRS Ford diff will need special axles to mate to the wheel hubs. They run into some cash but are worth it. If you go to stage 3 you will spend a lot but get near bullet proof axles and broached hubs.

I have pretty good detail in my blog of puting in Martians kit with an 8.8.

http://jimsmiata.blogspot.com/2013/0...-look-fat.html

Jim and Jenna build diary, Miata LS1 Conversion: The other half of the back half

Jim and Jenna build diary, Miata LS1 Conversion: OK so the start up goal was not such a good idea.

http://jimsmiata.blogspot.com/2013/0...back-half.html

Believe me, I feel your pain. I'm guessing you don't currently have the ability (welder or is it skills?) to just grind, perhaps reinforce re-weld the failed weld.

If you could repair the failed weld or even pay someone to do the repair it'd take the pressure off while you plan and execute your improved rearend setup.

I am not skilled in welding, nor do I have a welder.

I ended up taking it somewhere to have it fixed. It was under $100. Some stuff came up at home and I have very little money right now. So, I'm stuck with that solid rear for now. But at least Maggie is up and running agian. :D