Turbo Replacement
 

Alright so my car is the 89 Turbo II. I found out the turbo is completely screwed. Coolant got in it, the exhaust was billowing white smoke and the turbo was also pretty badly damaged. Needless to say I need a new one. The guy I bought it from said it only needed a new rebuild kit, but when my buddies and I try to hand crank the engine with a fairly large ratchet, we could only get a half turn at a time, no further. So what i'm trying to figure out is should I put a bigger turbo on it? If so what will fit? As I said in my introduction thread, I'm new to this. Lol

Another kind of off topic question I'm trying to answer is this. My buddies think that the compression is good since its so hard to crank it. When I got the car it would only run for about ten secs at a time. Would the turbo being as bad as it was cause the engine to run that rough? Or could I have something else seriously wrong?

anything other than a S5(89-91) turbo will need a manifold,downpipe and then FUEL to support it,..also an ECU to support that Fuel.
Unless you go with a Hybrid and some kind of trick parts( like fuel cut defender) and maybe an RTEK ECU that is programmable.
Just replacing the Turbo with something bigger is not as easy rip out and toss another one on.

If the engine not crank with the starter, then it has a major mechanical failure of some sort. This will require a complete rebuild, plus replacement of whatever parts have failed. This will cost between $1,200 and $7,000, depending on the parts required and how much labor you can perform yourself.

If the engine does crank with the starter, then check the compression to determine if the engine needs a rebuild. Be sure to begin the check with a good battery.
Rotary Resurrection - Compression Check

You can take your turbo unit to a rebuilder to see if it can be rebuilt. A basic rebuild is about $350-500, depending on your local rates. You can also send it out to BNR for a rebuild or upgrade.
BNR Turbos

A hybrid upgrade will also require
- Fuel pump upgrade
- Fuel injector upgrade
- Upgraded clutch, and maybe also an upgraded pressure plate
- One of the following:
a) RTek ECU upgrade
b) Aftermarket fuel controller, fuel cut defenser, boost gauge, and professional tuning.
c) Standalone engine management system and professional tuning.

A full turbo upgrade will require the above plus
- Turbocharger
- Turbocharger oil and water lines and fittings
- Wastegate
- Manifold
- Downpipe
- New air filter / box
- Optional Intercooler and/or ADI
- Optional upgraded exhaust system
- Somebody with the knowledge and equipment to install it properly. If you are new to this, then it isn't you.

Awesome thank you. Looked into BNR. I think I might go stage two hybrid with 710cc injectors and of course send the ecu to RTek and upgrade the fuel pump. Going to do the compression check Saturday. I'll let you know how she does. I appreciate your help!

OK guys here's what I've got so far.

Rtek7 stage 2 ecu(with zire71)
Bnr stage 2(might check with Brian. If he hasn't started it yet may go stg 3)
Greddy style FMIC
ACT clutch and pressure plate (6 puck unsprung hub)
Aeromotive 1000-6 FPR
Possibly getting Rising RPM fuel rails
And going with 850cc injectors (prim and sec.)

Feels like I'm forgetting something but idk. I believe that's all the important stuff. Lol Any input? Anything I need to do differently or better?
AEM wideband
AEM boost controller

No clue how the wideband and boost controlled got down there. I put em in with my list. Lol oh well

You still need an upgraded fuel pump and radiator.

The most common are the Walbro 255LPH fuel pump and Koyo regular or N-Flow radiator:
RX-7 Store - Walbro Fuel Pump
RX-7 Store - Cooling

The higher-end parts would include a Ron Davis or custom radiator (Griffin, Afco, etc.), and an SX or Aeromotive fuel pump.
RX-7 - Radiators - AWR Racing Store

Just a word of caution with BNR turbos. They ship the wastegate actuators with a 6 PSI spring. Not an issue if you intend to run stockish boost, but if you intend to bring it much past 10 PSI, then you'll have boost control issues. The backpressure from the tiny turbine will tend to push the wastegate open and boost will drop quickly at high RPM.

Ahh, that's what I forgot. It came with an aftermarket radiator, and I got the walboro 255lph fuel pump in it already.

Thanks for letting me know. I meant to ask Brian about the waste gate actuators. I know he can put better ones on. I'm thinking I'll probably run 14-15 psi, but not sure yet.

So here's the new..upper intake is back on, but, the new peice for the intorcooler piping required me to move a bracket which had a little black sensor of some kind clipped to it? Bent the bracket out of the way fine, but one of the nipples for the sensor broke off so for now the two lines that went into the bottom on the sensor are looped into each other and the third is capped off. What sensor or whatever was this thing? Is it important or can I just cap the lines the way I have them?

so you still haven't tested the engine which only rotates 1/2 turn but are throwing a bunch of upgrades onto it.


now that's the way to do it!


i have a used stage 3 BNR with low miles on it with the upgraded actuator sitting here if interested i suppose(nm, i just checked and it is a series 4 turbo). but i'd still get to checking on the engine before anything else.

I have already ran the compression test, and although I didn't hit 110psi I did hit 90psi on all three faces of both rotors continuously and was only turning at mabey 150 rpm. We have no suspicions that the motor needs rebuilt, but the if it does, tax season hits soon :) lol. My problem now is getting my palm to hot sync :\ I have the zire71. It won't even connect to its keyboard, much less my laptop. And I have already downloaded all of the software. Idk what the hell is wrong with it and I'm not the most computer savvy person in the world.

Were you ever able to get your motor to turn by hand?

Yeah we were. Turns out all three of us brain farted and forgot to see if the car was in gear...how? No idea. Lmao but I assure you we all felt pretty damn stupid afterwards.