bad piston rings
 

looks like all that smoke out the tail pipe is bad......
well time to rebuild
just ordered wiseco 8.5 -1 comp. pistons
323 gtr con rods
apr head studs
cometic head gasket
lets see how long this will hold up...
maybe this time ill get some sort of engine management...haha

Megasquirt man.

dont have the time to build it myself....
any ideas on some that makes a plug and play??

someone*

After a few of us get ours running on our own cars I think you'll have about 5 people that would be options for building you one and about 2 for making a plug and play setup that could either require some stock harness modification or not depending on connector type.
diyautotune.com will build and mod one for you for less than $400 unless i'm mistaken that will be setup with mods for a miata. Then you'd just have to wire it up.

probably last a really long time if you stop letting shops blow your engine and get away with it.