Hey everyone!
Iam about to buy a '94 Miata and a 2000 NB engine. My plan is to run a Garrett GTX2860R GEN II. Now all kinds of questions come to light.
Trans and diff-swap: My first idea was to take a Rx-7 TII (is there a diffrence between the s4/s5?)Trans with diff and throw it in but I read that just the non-turbo diffs fit. Also: Do I need a custom driveshaft?
Engine: I was going to increase the displacement to 1.9l by going 1.5mm overbore but read that this might be too much for boosted engines. Should I rather stick with the stock or just 1mm overbore?
Raspberry Pi: The pi is going to be conected to the 7" display wich will fit in a costum tombstone. I want to display several gauges aswell as being able to use it for bluetooth music etc. If anyone has experiences with the raspberry pi pls let me know ^^
I have way more questions but want to figure out most of it myself xD If I can't, I'll just ask here again.
If you guys need any other infos about my plan and what parts I will use just ask me! I'll be happy to tell ya!
Thanks guys!

 

RX7 transmissions don't bolt to Miata engines. And the '94 diff is plenty strong already.

 

I know that the trans doesn't bolt on but it's a common swap and I don't mind making an adapter plate and deleting the ppf. Do you realy think the stock trans will hold this kind of power?

 

TurboII transmissions have less than favorable ratios for low reving BP's. Best to look into the K Miata Getrag/ZF swap which have ratios better matched to BP performance.

 

From what I have read, the most common size is to go 1mm over and run 84mm 8.6:1 pistons if running boost. That will be my plan when I rebuild my 97.

 

You never mentioned a power goal.

 

Between 300 and 400HP!

 

Do you have a budget of $10-$15k?

 

Yep about 12k$

 

K-Miata BMW transmission swap kit is the easy button for drivetrain. I love my 6 speed from a 530i. Shifter feels like a bolt-action rifle. Miata 5 speed fails at 250ish whp. Miata 6 speed fails at about 300 something (mine failed).

Forged rods, 8.6 forged pistons, Supertech heavy double valve springs, Boundary Engineering billet oil pump, coolant reroute, Fluidampr or ATI balancer, would be the basic things to have.

Outside of that the turbo and manifold of your choice, big radiator, intercooler of your choice, etc.

You don't need to bore the block unless the machine shop says it is necessary. Increasing the displacement slightly by boring isn't a benefit to power in a forced induction engine with such poorly designed heads. Just turn the boost up a fraction of a psi and make up the difference.