floatyghosthat

iTrader: (5)

Hey guys,

I'm really sorry for starting another one of "those" threads, but I'm way in over my head here and could really use some sage advice.

I'm 5 hours from the nearest dyno, turner, rotary mechanic or even rotary owner. Suffice to say, I'm pretty much on my own out here. I've read, and read, and read as many threads as I can, but eventually it gets to the point where you could really use some specific advice, you know?

Anyway, here's the deal...

I've had my FD for 2 years now and have just got comfortable enough to start really messing with it. My plan WAS to do some minor mods this year, rebuild/port the motor next year and go single the year after that. I finally got my stock twins pulled, and they were toast. Coked real bad, and a HUGE crack right through the wastegate/housing.

I fought with myself as to whether I should just get a used set of stock turbos (very hit and miss), go with a set of BNRs (expensive, and a waste if I still planned on going single eventually) or just biting the bullet and going to a single. I decided the last one made the most sense.

When deciding on a turbo, I contemplated a few options but eventually decided to do it once and do it right. I went with a GTX3582R kit from RX7store. I figured the BB/billet combo was worth the extra cost for what I wanted.

I've spent the money, the kit is on its way, and now I'm kind of freaking out. Here's where my car stands;

1993 JDM FD Type-R
50,000 original miles
-STOCK motor (never been touched as far as I can tell)
-Power FC
-Koyo Rad
-Defi boost, oil temp and coolant temp gauges

Here's a list of parts sitting on my bench, waiting to be installed;
-Pettit Coolcharge 3 Intercooler
-Datalogit
-electronic fuel pressure gauge (I don't plan on using the gauge, just the signal for datalogging)
-Fast acting AIT
-AST delete kit
-Resonated midpipe
-Knightsports Cat-back

Parts on the way/soon to be ordered;
-GTX3582R
-Rx7 store exhaust manifold and downpipe
-Tial 44mm wastegate
-Hose Techniques vacuum lines
-RX7 store fuel kit with Aeromotive FPR and 1600CC secondary injectors
-PLX wideband, dual EGTs and DM-100 multigauge
-Snow Performance Stage 2 meth injection kit (I will be running water only for now)
-Spec stage 3 clutch

Other stuff;
-ACV delete
-dual throttle delete
-OMP delete
-Air pump delete


As it stands now, the engine is pretty much down to the block and lower fuel rail. All the manifolds and piping are off, I just gutted the rats nest, and I'm waiting for my fuelling to arrive before I can start putting it all back together.

As for my intentions, the car will be a DD with occasional track and drag strip use. All I really want for now is around 400WHP, with room to grow. Ideally I'd like to get into the 11s, but that will be more practice than anything.

A few of the KEY questions that I really need help with;

1) The big one; can my engine handle this turbo? I'm really afraid of blowing my engine, and I've heard everything from "The stock engine is bullet-proof and will handle anything if tuned properly" to "Anything over 14psi and it'll blow unless it's dowelled/seals/build/ported". I know the water injection will help quite a bit, I'd just like a solid answer as to what I should really be aiming for power/boost wise to be on the safe side of things.

2) Is there anything I'm missing? Being a quick build without a lot of knowledge, I'm very scared that I've overlooked something. Ignition maybe?

3) I have a strong suspicion that my fuelling won't be enough for the turbo. Any estimates on how much boost the 550/1600 combo will get me with the GTX?

4) I know this is more of a "Power FC forum" question, and yes, it's a stupid one, but I figured I'd try here first... How can I tell if my Power FC has the boost control solenoid? When I imported it from Japan, it was running slightly higher than stock boost, which leads me to believe I might have the solenoid, but I'm not sure and don't really know where to look.

5) Any idea (ballpark) how much vacuum line I'll need with a single turbo set-up?

That's all the questions I have for now. I'm sure I'll have more as the build progresses. I'm hoping to have it done by the end of April. Any advice you guys have would be GREATLY appreciated.

Thanks!

-Devan

arghx

iTrader: (3)

You kind of answered your own question. There are different opinions out there and no real consensus. Hopefully your current engine is healthy. Now one thing you will probably hear is that the old OEM 3 piece apex seals are prone to separating under detonation. That's one thing to be concerned about. It's much cheaper to rebuild an engine before it blows up. If the budget can handle it, I'd pull the motor and get it freshened. A 2 piece seal is going to be more forgiving. You are going to feel like an idiot if it lets go after 6 months for whatever reason. I bet the housings and bearings are still in great shape. Also, a fresh set of coolant seals will probably withstand an accidental overheat better.

HKS Twin Power is the go-to ignition solution for most setups because it's clean and simple to install, it boosts spark well, and it amplifies both leading and trailing. You should get a 3 bar MAP sensor. If you don't get the Apex'i sensor I'd recommend getting the GM sensor from Banzai Racing because they have a plug-and-play adapter (why cut wires when you don't have to).

Depends on fuel pressure and how generous your dyno is. I would not recommend larger primary injectors since there are now very large secondary injectors widely available. I would run at least 3 bar fuel pressure (43.5psi).

You'd see it mounted somewhere, and the stock wastegate solenoid on the UIM would be unplugged. Normally it comes as part of a kit like this:



there is a 3 port solenoid (right) and a 3 bar MAP sensor (left). You probably don't have it installed if the car was on sequential twins. If you want to control boost with the Power FC and not buy the kit, the simplest solution would be for you to get the GM 3 bar MAP sensor from Banzai Racing and get the MAC 3 port solenoid which is functionally the same as the Apex'i unit.

Hard to say. I like to run the main wastegate line in stainless steel. Most of the vacuum lines will be 3.5mm (or 5/32" if measured with standard units).

Turblown

iTrader: (12)

You will run out of pump before injectors( assuming you're just on one single intake pump) If you didn't get the 1.06 a/r the billet upgrade is a complete waste of time.

floatyghosthat

iTrader: (5)

I did go with the 1.06. I figured the same thing.

I forgot to mention that I do have a Walbro 255 for now. I think my plan is to run with that for now, and take whatever power I can from it. Once my budget allows, I plan to go with a twin Denso set-up.

As for the boost controller, I think I'm just going to keep the Power FC as my stand-alone and go with an AVC-R or something else as a separate boost controller. I've heard that the Power FC isn't an ideal boost controller, but we'll see.

As for the rebuild, I'm way in over my head right now as far as my budget is concerned. I'm pretty sure that my girlfriend would kill me if I spent another 3 grand to get the engine rebuilt right now, but I'll see what I can do. I would obviously feel much more comfortable with a built engine, but it might not work out for this year...

Thanks for all the advice guys, I really appreciate it.

-Devan

arghx

iTrader: (3)

Power FC boost control is like an AVC-R with much less adjustability. You've got two settings that you play with. AVC-R uses the same solenoid as the Apex'i boost kit. It's a great boost controller but only if you know how to take advantage of it. Technically in its simplest mode you can adjust it like the Power FC. But it's really not an entry level "I just want to run x psi" controller. People get frustrated with it easily. It is modeled after OEM boost control systems. To use its full potential you need to have a very solid understanding of boost control theory.

If you want a simpler set up get a Greddy Type S. It also uses the same solenoid as Apex'i (solenoid is rebadged) but it has simple ***** for adjustment, almost like fiddling with a manual boost controller. You can dial it in very quickly. Compared to the AVC-R you don't get boost-by-gear or the ability to adjust the boost curve through the rpm range.

floatyghosthat

iTrader: (5)

I'll definitely look into the Power FC and AVC-R as well as others. Although I am still slightly naive when it comes to the electronic aspect of the set-up, I have every intention of learning everything I can from the inside out.

I went to University for Aerospace Engineering and have an unhealthy obsession with spreadsheets. I am just as excited about tuning the car as I am about driving it. I'm pretty stoked about the concept of boost by gear and other various aspects of more advanced boost control. I have no problem taking the time to learn the intricacies of the system to take better advantage of my turbo set-up.

arghx

iTrader: (3)

Awesome. That's the attitude you need to have. Start by reading this article here: http://www.perrinperformance.com/pages/show/113 with the aftermarket electronic controllers + external gate you are using a 3 port solenoid to push on the top of the diaphragm, similar to this arrangement:



The ports are sometimes arranged a little differently on different brands of solenoids but they work exactly the same way. The stock wastegate and precontrol solenoids are 2 port designs. You can see that that article is aimed toward Subaru owners and tuners. That's because Subarus have one of the most sophisticated boost controls systems available that can be tuned easily, and it is built right into their factory computer. In most ways an AVC-R is like a dumbed-down version of what a WRX owner got from the factory.

floatyghosthat

iTrader: (5)

Thank yuo very much arghx, that was an excellent read. It all makes a lot more sense now. I've dealt with MBCs before, but I've never really understood the 3 port thing with the EBCs.

I'll definitely be going with an EBC, it's just a matter of which one. Do you have any recommendations?

arghx

iTrader: (3)

Shorter answer:

-- For the "I just want it to work" types I recommend the Profec-S because it's hard to screw it up. There are two *****. If for whatever reason boost is a little too high one day, you just turn a ****.

-- AVC-R gives you much more control (gear & rpm based duty + gain adjustment) but with a much steeper learning curve. here are the instructions http://www.apexi-usa.com/content/pdf6115.pdf

-- Power FC is integrated into your data logging so you can have spreadsheets of your duty cycles. It is the cheapest and cleanest solution (just plug a 3 port solenoid into factory harness or you can rig up the factory 2 port as I have done). It is integrated into the Commander and the PFC overboost protection system. It has limited control over the boost curve. You can't directly adjust the gain.

-- I don't recommend stepper motor type EBC's. There aren't many of them anymore. The old Greddy Profec B, the predecessor to the Greddy Profec S, used a stepper motor. Some of the HKS boost controllers use a stepper motor. I don't recommend them mostly because they aren't widely available and if the motor goes bad you can't get another one easily.


I'm bored at work right now so here is a more technical explanation:

Given your engineering background you must have at least been introduced to controls. A couple cheap controllers are completely open loop (AEM Tru Boost, some ebay controllers). Most other external electronic boost controller use a baseline duty cycle value and some implementation of proportional gain only (not PID, not PI, just P). Like any kind of proportional control, it has a tendency toward overshoot and oscillation if you're not careful. The instructions for a lot of aftermarket controllers are pretty bad and percentage wise few people understand basic control theory so they can't sort through it. So people have big problems with overshooting and oscillation. Those are the most common complaints you will hear about particular boost controllers. "It sucks" "It overboosts" "I think my solenoid is broken" are often problems caused by user error that can be attributed to poor instructions and a lack of knowledge.

For you specifically I'd say go with the AVC-R because you are willing to devote the time to it. You will get boost-by-gear capability, rpm-specific duty cycle adjustments and gear-specific gain adjustments. So each gear has a 2D boost target vs rpm map, a 2D baseline duty cycle vs rpm map, and a proportional gain scalar. It has no air temperature compensation but neither do any other external controllers. There are some other minor features such as a useless "self learning mode" that you should turn off. You don't have to use all the rpm and gear-based stuff but if you don't use them IMO there is no point in owning this controller. Note that this is going to have the messiest and most complicated installation of any controller. You have to tap wires at the ECU, install a solenoid and external pressure sensor, and run harnesses through the car. I prefer having a patch harness for the ECU when doing this kind of install, which Banzai Racing and Boomslang sell. It's much easier to tap into and you don't risk screwing up your harness.

To put things in perspective, if you had an 08+ STi you would just use the highly sophisticated factory boost controller built into the ECU. You have 3D duty cycle and boost target tables that take into account throttle position as well as rpm. An AVC-R uses a proportional gain scalar (they call it feedback speed). On a Subaru you get proportional and integral gain. They are arranged as 2 dimensional tables which adjust the proportional and integral control based on the calculated boost error. There are air and water temperature compensation tables to both the baseline duty value and gain. This is actually really cool because the PI control is much more sensitive at colder temperatures. Another cool thing is the integration with the knock control--if enough knock is detected, the ECU will run wastegate pressure. A few Subarus have some gear-specific control but most of the newer ones at least have a "low gear" correction factor. I have never seen an aftermarket controller (even built into expensive standalones) that have this overall level of sophistication. Evos use a simpler boost control architecture, which interestingly enough uses proportional control only.


Power FC boost control is a significantly dumbed down version of the AVC-R. There is no gear based control and there is no setting to directly control gain (the PFC sort of figures it out for you based on the boost and duty setting you use). It has no air temperature compensation like say an AEM EMS has built into its boost control capability. However, since you are using the Power FC for engine management you can directly log what the boost control solenoid is doing and integrate it with your spreadsheets and charts. With an external controller you can't do that.

You can switch your boost settings with the Commander and you won't have to install a separate box and wires in the car. You can buy a cheap 3 port solenoid from MAC for about $30 or if you are a cheap bastard like me you can actually use a stock 2 port solenoid with your external wastegate if you plumb it right. The Power FC boost control is directly integrated into the overboost fuel cut, which is your last line of protection in the event of wastegate failure. You can still use fuel cut with an external controller though.

On my personal car I use the Power FC. It has its advantages and disadvantages. I use it because of the cleanliness (I have a thing about minimizing aftermarket boxes and wires) and the integrated datalogging. I wish it had more adjustability but it certainly gets the job done and I've been using it for about 2 years now.

floatyghosthat

iTrader: (5)

Thanks again arghx!

From everything you've said, I think I'm probably going to go with the Power FC for boost control. I'm a very big fan of datalogability (pretty certain that's not a word), and sacraficing a little bit of control to have better information is worth it to me.

Now it's a matter of putting together a system that works, and the even more daunting task of reprogramming my nearly stock PFC to handle my new single set-up. It looks like I have A LOT of reading ahead of me...

arghx

iTrader: (3)

this thread discusses Power FC boost control https://www.rx7club.com/single-turbo-rx-7s-23/long-term-testing-power-fc-single-turbo-boost-control-900599/

floatyghosthat

iTrader: (5)

Thank you again sir!

Now, without getting too ahead of myself...

If everything goes according to plan (which I highly doubt), this is where I hope to have everything electronics-wise...

PLX multigauge showing wideband, dual EGTS and fuel pressure, or water injection flow (somehow).

Power FC (properly tuned) running as my stand-alone and boost controller.

Dataloggit, logging all the PFC stuff as well as wideband, dual EGTs, fuel pressure and water/meth flow.

Defi gauges on my dash showing water temp, oil temp and boost.

Is there anything that I'm missing? Like I said, dataloggability is a big priority for me...

DriftDreamzSS

iTrader: (4)

I would recommend getting a new manifold and ID2000 injectors. My rx7store 3582r kit came with a horrible ebay manifold, and its nice to not have to wire resistors into your harness or buy an additional injector driver when there is a cleaner and higher flowing solution. Ive been very happy with my pfc controlling boost. Also, with the datalogit you can toggle Hi/Low boost on the fly without navigating menus in the commander. I have mine wired to my previously unused fog light switch, it works great.

arghx

iTrader: (3)

Nice. I had read that it's possible but I haven't seen it done. If I were willing to permanently mount my Datalogit I would do that.

floatyghosthat

iTrader: (5)

That sounds great. Is it difficult to do?

DriftDreamzSS

iTrader: (4)

It's super easy, Run 1 wire from the switch to sw4 on the datalogit, ground the other wire of the switch and enable the features in fc edit.

floatyghosthat

iTrader: (5)

Awesome. I will definitely be doing that. Thanks.

My own secret "go faster" button. Muahaha.

Jason

iTrader: (5)

We have switched manifolds to a nicer setup.

floatyghosthat

iTrader: (5)

Hey Jason,

Am I going to need to wire in resistors for the injectors?

Jason

iTrader: (5)

There are two clips that come with the fuel system. You wire one resistor for each clip. Very easy to do.
I have pictures of the fuel system install I can send you.

Jason

floatyghosthat

iTrader: (5)

That would be great, thanks Jason!