So I'm finally nearing the final steps in my first attempt at an ecu install. I figured I would tidy things up a bit under the UIM while I was in there, so I went ahead and removed all of the emissions related solenoids and hoses. My problem now is determining how to configure the remaining solenoids to control the turbos. I have seen/read two methods to do this and neither seem to be complete (nor do they match.. at least to me).

By my count, there are 6 remaining solenoids:
Turbo Control (x2)
Turbo Pre-Control
Charge Control
Charge Relief
Wastegate Control (I also received a free Haltech Boost Control Solenoid when I bought the ecu, so I was planning on using this here).

I guess my question really is, do I need all of these solenoids? If so, what is the staging or sequence that they need to be fired in? I have relays and PWM outputs available. I am confident that I can wire everything correctly.. my major problem/concern is that I don't fully understand all the behind-the-scenes activities that control the sequential system.

Any help or enlightenment would be greatly appreciated.

Greg

 

find the workshop manual and find out when each switches.

Just for the ease of things, I'd use 2 MBC to run the Pre-control and Wastegate...it will free up outputs and make tuning easier.

The only ones I think you'll need are...

a turbo control to move the flapper in the exhaust manifold
a charge control to move the butterfly in the y-pipe
a charge relief to close the CRV.

sounds like a fun project!

http://www.turborx7.com/rx7vacuum.htm
^should be helpful

 

Since I'm feeling nice and I like this project.

Turbo Control - idle B+, around 4500rpm <1.0V
Charge Control - Idle <1.0V, around 4500rpm B+
Charge Relief - idle B+, 3000-4500rpm <1.0V for 4-8sec.

Charge relief sounds difficult with an aftermarket ECU...probably another way around it.

I say around 4500, because you might get better transistion if you run...say 14psi transistion at 4200. Depends on twins and boost.

 

Dubulup, you've peaked my curiosity, how proficient are you with the Haltech's inner IdleX wire workings? and how to control them?

And also, what outputs are we talking about exactly? arent most of those solenoids PWM switches, or just On/Off deals?

 

I was just stating what the WSM has (except I edited there 5500 with 4500...as we all know that is where the transistion is). So, <1.0V could be 0.0V.

I'd recommend using the dual intake valve setting for all of these.

RPM ON around 4500; OFF 4300

you would need to wire relays to either give or take away the 12V.

for the charge relief...maybe a timed relay of some sort.

charge relief has to feed off the vacuum chamber while the secondary is prespooling so the valve is open, once the secondary comes online it needs to be shut or that will act as one hell of a boost leak.

 

Wait, now you're talking about using the PWMs? i thought you had some sort of advanced knowledge of the IdleX wires that would allow you to use the Idle motor controls for these things?

And you didnt answer my question.

 

Claudio, I beleive he is referring to the rpm range when he mentions Idle (B+ refers to +12v battery).... If I'm wrong here, everything below makes no sense.

This sounds like a single relay/PWM signal could be applied here using the normally open and normally closed contacts.

Charge relief does sound tricky. I will think about this some more over the weekend.

I haven't looked through the FSM yet (will do that this weekend), but this is my current understanding of what you described above. Hopefully I'm not too far off track.

RPM Range Solenoid Status
0 - ~3000 Turbo Control ON (directs exhaust through turbos)
Charge Relief ON (vents secondary turbo to atmosphere)
Charge Control OFF (closes off intake side of the secondary turbo at the y-pipe)
~3000 - ~4500 Turbo Control ON (primary turbo is still boosting)
Charge Relief OFF (closes CRV, secondary turbo builds boost)
Charge Control OFF (secondary side of y-pipe still closed)
~4500 - shift Turbo Control OFF (closes off exhaust to turbos????)
Charge Relief ??? (This stays closed, right?)
Charge Control OFF (secondary side of y-pipe opens)

As you could probably tell, I am getting a little confused around the transition period.

The wastegate control is pretty self explanatory, but what is the function of the turbo pre-control solenoid? If I had to guess, you use the mbc to set it to begin spooling the secondary turbo at a certain pressure.

Thanks for the information thus far. I hope you are still feeling nice

 

sorry, I'm not proficient with the Haltech's inner IdleX wire workings at all...simple PWM outputs is what I was thinking. Not sure what I said to make you think otherwise.

 

Ok, dont feel bad, i think Haltech only knows exactly what dose wires do.

Anyway, i guess that yes, with enough PWMs you can control all those actuators for the TT's, but, then again, i think that if you want great power you wouldnt stick with the stock twins. And any twin turbo upgrade that would be worth it, would consist of a custom fab manifold and at least a nice pair of GT28's, but thats just me.

 

correct
correct again
basically correct
Tubro Control
When the turbo control solenoids (there are two; one supplies pressure the other vaccum, but use one ECU output...sorry I left that out) are idling (12V) the actuator has the flapper closed. Routing two exhaust ports thru one turbo. When they switch over at 4500, two exhaust ports flowing to two turbo's. The vacuum solenoid might be able to be avoided, but I think the actuator would lag a little...I'd give it a try with both at first.

Charge Relief
charge relief solenoid has 12V at idle; This needs to close the CRV, with atmoshere or positive pressure.

Charge Control
0V at idle. The actuator will have the y-pipe butterfly closed. This is to insure the primary turbo doesn't pressurized the back half of the y-pipe and backspin the secondary turbo.

at 3000rpm the primary should reach full boost (10psi in the stock case). At this point the precontrol (wastegate of sort) vents excess exhaust gas to the secondary turbine and starts it spooling. Now this this turbo is creating positive pressure it needs to be vented...charge relief drops to 0V, and now the vacuum chamber pulls the CRV (BOV of sort) open and the positive pressure returns to the air box or atmoshere, where ever you pleasure.

Now the maroon line is starting to become positive pressure...
Turbo Control drops to 0V, Now exhaust flows to both turbo's directly from the engine.

Charge Control should go to 12V. This allows the actuator to open the butterfly valve. Allowing the secondary turbo to send pressure thru the y-pipe.

Charge relief should drop return to 12V closing the CRV once the butterfly in the y-pipe allows boost to pass. If not you will be loosing quite a bit of pressure to the air box.

You can use a MBC to set when the primary starts to prespool...and adjustments in the actuator rod can increase/decrease flow as well.

 

Based on your info, I think this might work (attachment).

Relay 2 would turn on around 3000rpm; Relay 1 would turn on around 4500rpm.

My current goal is to get the car running again at, or close to, stock levels (only mods are mp, dp, catback, and intake). Next steps are intercooler and fuel (probably up the boost here too). Eventually, I'll go single turbo, but not before I get tired of the sequential twins.

Anyways, comments are welcome (especially if this diagram won't work).

Dubulup, thanks again for the help.

 

first thing I notice is the precontrol...it's not an ON/OFF solenoid, its basically just like a WG. Needs to be pulsed (feedback), to maintain certain boost level in the primary. If you insist on the Haltech WG control, maybe look into a MBC to tune the precontrol.

The way you have it drawn, the precontrol will fully open and probably overspool the secondary while you lose boost pressure on the secondary.

read this link.
https://www.rx7club.com/showthread.p...erfect+10-8-10

Other than that, your logic looks good. Judging by your NC and NO symbols, I believe your job involves some sort of controls???

Good idea with the charge relief diode.

 

That link pretty much cleared up any remaining questions I had about how everything worked. I ordered a manual boost controller today for the pre-control actuator. I really wanted to use the supplied Haltech wastegate solenoid to take advantage of the closed loop boost control, but even if I use it, the primary turbo boost setting will still be controlled by manual controller. Using the mbc should really simplify things though. I also picked up some diodes off of ebay, so hopefully I can get this put together next weekend.

I am hoping to have some results to post before the end of the month.

I had a co-op at an electric utility when I was in college. I worked in the protection and relaying department, so I saw quite a bit of control circuit logic. Seems to have come in handy here.

 

you still should be able too.

even using the MBC on the primary. The only thing it will control is how much the secondary spools, the WG still went vent the primary to keep manifold pressure in check.

say you have a 10-6-10 pattern...twist the MBC until it reaches 9, which you should be able to do.

GOOD LUCK!!

 

Update

 

I have everything together for the turbos... I am still waiting to get some parts back from the machine shop before I can put the rest of my engine bay back together. I am definitely getting antsy though. I picked up some really nice diodes off of ebay. They look really beefy and should be perfect. Lets hope it works!

 

Progress?

 

Had to put the car project aside for a while, but I'm back on it now. As soon as I get this ignition problem sorted out, I'll be able to install what I made and see how it works. I did test the control logic and it looks like it will work... just a matter of installing and tuning.

 

I was wondering when I'd hear from you again...keep us posted...with pics too

 

I have some more pictures of the finished product, but they are still on the camera. This is the mock up I made before I fastened everything for good and it's a little out of focus, but you get the idea.

http://rx7.ninetwelve.net/pics/sequentialcontrol.JPG

I'll probably add some LEDs that will be on the outside of the control box for troubleshooting purposes.

More later.

Greg

 

that is pretty cool! I'm very excited to see some results!!

 

any update here?

 

Ok guys, here it is, an easyway to control the stock twins on an FD using 2 outputs, 2 relays and 4 solenoids. I have spend a whole day with one trying to get it to work, there have been some post about this with information on how to wire the relays up but there seems to be something off with the info.

First, you need to connect 2 of the solenoids to 1 of the relays, one of the solenoids will get power from pin 87 of the relay, the other from 87a, the reason for this is that when you apply the ground circuit (from the haltech PWM) to switch the relay, pin 87a will have power and when the circuit is closed with the PWM power switches to pin 87. So, one of the solenoids will be feed from the pressure canister and the other from the vaccuum canister.

Second, you connect the 3nd solenoid to the Charge Control solenoid (flapper for the secondary turbo) along with the soleniod been feed from pin 87 of the first relay. Using our first PWM set to Dual Intake Valve, have it activate at 4000rpm and deactivate at 3800.

Third step, our 4th solenoid will be wired up to our 2nd relay, on pin 87 normally, and will be triggered by our 2nd PWM output at 3800rpms and deactivated at 3600rpms. This part of the equation will make the prespool trap door in the exhaust manifold help to bring up the secondary turbo upto speed before the switch over.

Now, to properly connect the vaccum hoses in this equation, you will need the "Simplified Vaccum Diagram" found HERE.

Finally, to take control of boost pressures, you will need either a 3rd PWM output from the Haltech, and using an adequate solenoid control the Wastegate actuator, or a good stand alone boost controller (like the greddy profec b old style).

 

Here is a diagram of how we did it. RPM points are only sugestions. You can tune yours to what ever you like.

PS. Donations accepted through Paypal! Thanks!

 

Claudio
I want my double whopper and vanilla shake!
The way I see it you owe me that much for my entire two mins of confirming what you all knew allready.