DOHCterMiata

I have a 160,000 mile 88 gxl it has 30 pounds of oil pressure at idle 60 pounds at WOT and runs pretty good.
How safe is a turbo?? If it was a piston engine I wouldnt hesitate but the rotary is few and far between now, and I really dont want to kill it fast. What would the lifespan be on a small mitsu turbo intercooled with the stock computer?

RETed

You want to turbo your NA?



-Ted

DOHCterMiata

Absolutely, I have a 94 miata I fitted a tdo4 mitsu turbo with no intercooler and stock computer. I fabricate everything myself this is not the issue.

Will a 160,000 mile rotary handle boost safely with an intercooler and the stock ECU?

Spool Up

What are you using to enrich fuel after atmospheric pressure is reached? I'm pretty sure that a naturally aspirated car's ecu does not come with boost fuel tables already on it, but I could be wrong. I had a turbo kit on my old Integra and I used a Vortech FMU(Fuel Management Unit) to add more fuel after atmospheric pressure was reached. I also had to use a check valve to keep the ecu from reading any boost. Are you running any type of FMU on your Miata?

DOHCterMiata

Im not runing anything right now, If I can get the fuel and timing worked out. Can I safely run boost at the age of the engine?

DOHCterMiata

Sorry.
I am runing an Auxilary Fuel Pressure Regulator It sees boost via a vacuum line and it restricts the fuel returning to the tank which builds fuel pressure at the injector rail. Making the injectors squirt more fuel.
Timing is retarded to 10* BTDC

Bambam7

You will shorten the life of your engine- but not if you aren't hard on it all the time.

The problem is, the high compression rotors don't like too much boost, before they start detonating and cracking apex seals.
If you run appropriate enrichment (S-AFC, or an FMU), retard the timing a bit, and run a nice front mounted intercooler, you can run 10 PSI of boost max. This is about what the stock turbo would put out when coupled with an intake and exhaust
If you want to swap in turbo rotors... go ahead, but then you might as well swap in a the turbo engine, tranny, and rear and too!!
ANywasy, 10 psi- This is the max SAFE level.... Of course you can run more, but you may start cutting into engine life. Lots of insturmentation is vital if you want to do that too (Fuel pressure, wideband 02 sensor, (or EGT) boost gauge, and oil pressure)
Without intercooling, 5-6 psi is about max. You will still need fuel managment though.
You can also run more boost with water injection, or a knock sensor.
It's all a tradoff of speed and engine life!

Also- if you have the means to fabricate the turbo mounting and piping, then you also can probably rebuild the engine if you need. It's DAMN easy to rebuild a rotary, it just needs a few special tools, like to get the flywheel off. It's WAY easier than doing a piston engine IMO.

Also- the stock TII (Turbo rx7) turbo and manifold will bolt right on with the help of a 2 1/2" wide spacer on the manifold.
You will also need a turbo version fuel pump, and at 550cc injectors... at least 2 for the secondaries, but preferably all 4.

amemiya

why does everone think that rotary's are so sensitive?? like about the propnae injection?? and running octain boost. for gods sake they had rotarys run on hydrogen.

ok it is not spelled right