ramses666

iTrader: (1)

Well, I finally got my activation system finished & it works perfectly!! I had done a manifold swap & put a s5 intake on my s4 NA, but was frustrated with the whole port/VDI activation scheme. Here's what I did -

I purchased two Summit digital RPM switches, a VDO 15 psi Boost Gauge, an autometer A-pillar gauge, a gauge hose kit, a mini-pressure regulator and some gm style door-jamb switches all from Summit Racing.

I went through my old rats nest and found some solenoids and a one-way valve and salvaged a piece of the rack to mount two solenoids.

I went to radioshack and picked up a barrier mounting strip, some different kinds of wire and connectors and a pack of assorted LEDS and some 330 ohm resistors.

A buddy gave me an old black plastic fuel tank from a lawnmower. It had a slight kidney-shape to it and looked like a good fit to go around the charcoal cannister in the engine bay. I mounted the mini-pressure regulator to the tank and the one way valve was a perfect fit in the tank outlet. I then sealed the tank up and started pressure testing it for leaks. I hooked my Boost gauge up to the adjustable mini-pressure regulator. I'll be damned if the mini-pressure regulator was leaking out from the sealed bottom... I put some JB weld on it & stopped the pressure leaks pretty good... it would hold pressure for about an hour or two - so I figured that was good enough.

I started experimenting with the solenoids from my old rats nest and the pressure tank and found that the port actuators work really good between 5-10 psi. If I used too much more pressure the solenoids would stick open. I mounted the pressure tank to the charcoal cannister with some hose clamps and it fit very well. I mounted the bracket for the solenoids on the same hose clamps. Some new vacuum hose hooked up the port actuators and VDI. I mounted the electrical terminal strip to the shock tower and the two RPM switches on the existing bracket holding the idle mixture pot.

I was curious to see how much pressure my Racing Beat header would put out so I hooked it up to the tank inlet & oneway valve. I got maybe 2.5 psi at about 5k rpms - not enough for me - so I purchased a cheap mini-air compressor at the local auto-parts store. I found it took only a few seconds to charge the tank with air so I wired the compressor to a switch I had previously mounted on my e-brake handle for my windshield wipers when the control unit for them took a dump.

I wired up the RPM switches & set them for 3600 for the 5th & 6th ports and 4800 for the VDI and got all that to work pretty easily. It worked really good but I wanted to know exactly what was working when, so I used some door-jamb switches and made some brackets to mount them above the actuators so that when the actuator was fully open the switch would make contact to ground. It was pretty easy to get them mounted and adjusted for the 5th & 6th ports but the door-jamb switch wouldn't work on the VDI very easily. I ended up putting some heat shrink tubing around the VDI stop tab that keeps it from opening to far and then I wrapped some wire around that & soldered it to keep it together.

Why do all that? Well I used 6 mini & 2 regular leds to indicate all the conditions that were going on -
regular orange led - air compressor power on
mini-green - 5th & 6th port RPM switch power & BELOW RPM threshold
mini-green - VDI RPM switch power & BELOW RPM threshold
mini-yellow - 5th & 6th port RPM switch ABOVE RPM threshold
mini-yellow - VDI RPM switch ABOVE RPM threshold
mini-red - 5th port FULL OPEN via door-jamb switch
mini-red - 6th port FULL OPEN via door jamb switch
regular red led - VDI FULL OPEN via stop tab wire

I mounted all these led's and a resistor for each one as well into the a-pillar gauge pod along with the boost gauge and wired up the gauge light to the cluster dimmer control. So now I can see exactly whats happening... I think it looks really cool as you rev the engine the lights go off & on and the gauge needle really kicks down when the solenoids trigger.

When the pressure tank gets a little low I flick the switch on the e-brake handle and the compressor fills it back up. It only takes maybe 2-3 seconds for the compressor to give enough for at least 3 or 4 pulls. If I need to I can leave the compressor on longer and have more reserve pressure in the tank but the mini-pressure regulator keeps me right around 10 psi available for the actuators.

This mod had alot of wiring but nothing really complicated. The barrier strip I used made it really easy to keep track of it all. The RPM switches use a switched ground and a constant positive that comes on with the ignition so I used that through out so that if a switch or wire fails to the chassis it won't knock out anything. I ran all the wires through the speedometer cable hole in the firewall and rigged the compressor with a quick disconnect so I can take it out of the engine bay & use it to pump up the tires or whatnot.

I spent about $300 on this setup but it works perfectly, reliably and I can monitor every function. I thought using the old gas tank was significant... when my buddy showed it to me I was inspired and knew exactly what to do with it & it looks like it was meant to go exactly where it is. Oh yeah... the gauge setup looks even better at night - the boost gauge came with a red or a green bulb sock - the red one looks pretty close to the stock orange cluster lights. The car really pulls good now with the 5th & 6th ports & the VDI functioning correctly. Full throttle pulls are very smooth. At half throttle you can really feel the VDI kick in. Its cool watching my "boost" gauge kick back & forth and I like having compressor control on the e-brake handle.

Thought someone might find this helpful or interesting. I would like to thank this forum & its members for providing lots of helpful ideas & posts. The search button works great!!!

Ramses666

ramses666

iTrader: (1)

I did a trial in the driveway... it took about 7 pulls to run out of pressure. At about 2.5 psi the actuators wouldn't open anymore. It's so cool to be able to rev the motor & see whats happening with the ports and the pressure. It adds the missing dimension to driving an NA. You can see the needle bounce & see the lights showing full open & feel the power. Better rush than the roadrace true dual exhaust & k7n intake. The VDI makes a big difference in the small NA pond.


Ramses666

The Shaolin

iTrader: (5)

Very cool, but WHERE ARE THE PICTURES?!

scrip7

iTrader: (6)

It appears that you have put quite a bit of thought into making the ports/VDI work without the aid of the air pump. The RPM switch idea is an established way to tailor the opening trigger points.

There is an easier way to verify that the actuators/VDI are indeed opening as intended, without rigging up door jamb switches and LEDs:

Purchase an inexpensive vacuum/fuel pump gauge (vacuum scale on one side, pressure on the other) from an auto parts store. Tee the gauge into the hose from the air pressure source (hobby compressor, lumbar pump, etc) to the actuators and measure how much pressure it takes to open the actuators at the rate that suits you. If, for instance, it takes 2.5 psi on the gauge to open them, temporarily move the gauge to where you can glance at it while driving. I use a long piece of vacuum hose and tuck the gauge under one of the wipers so it's easy to see it without it being too much of a distraction. I use this method when checking a customer's port actuators/VDI and it works well to find bad air pumps/solenoids/exhaust backpressure, etc. Obviously, if the correct pressure is reached, it's safe to assume the actuators are operational.

ramses666

iTrader: (1)

I do have a gauge connected that very clearly shows the amount of pressure applied. The reason for the door-jamb switch is to indicate full port opening - I already have a led for the rpm signal to the solenoid - I wanted a physical connection to be indicating the open or closed status so that I knew the actuators were in fact all the way open or how fast they close on deceleration - and individually as well.

I took alot of time thinking about it & this is what I came up with. I really like the pressure holding tank & mini-regulator... These were the items I hadn't seen used in this application before, but seemed like a good idea to me. It sure is alot more fun to have it all as a show to watch... to know it's all working right and running very well....

Comments?

Ramses666

88RXVERT

iTrader: (5)

I did the intake swap in my Old S4 NA, it's not worth a **** and a total waste of time and money.

Roen

iTrader: (2)

Try setting both 6PI and VDI to 4200 and see what happens.

lastphaseofthis

iTrader: (8)

what he needs to do is go to the dyno and run with them all closed, aux ports open vdi closed, vdi open aux ports close, then all open, and crossing the dyno graphs were they intersect will give the best performance.

ramses666

iTrader: (1)

Why change the rpm trigger points? I set them a little lower than stock already - 3600 for the 5th/6th ports & 4800 for the VDI. It was a guestimate I used because of the time it took for the actuators vs. speed of rpm increase during a pull. At full throttle in first & second gear it is really smooth and pulls hard as far as I dare to go - maybe 7800 rpms or so.

The digital summit rpm switches are really easy to set exactly. I suppose if I had access to a dyno for a while I would play with it more, but right now it seems to be working nicely. At half throttle it's smooth up to the VDI then it kicks in with a good surge of power. I am happy with the S5 upper & mid intake on my S4 lower. It took some doing but I think it was worth it - they came with the used longblock & tranny I bought for $350. It was an S4 core with all S5 intakes & accessories. I kept my S4 throttle body & front cover & OMP & S6 alternator. I'll try & get some pictures today.

Ramses666

Roen

iTrader: (2)

The factory rpm points are too early for the 5th/6th and too late for the VDI. You can improve your midrange if you set it to the right points.

I have an Rtek, so I can change the activation points via the ECU. Take a look at my thread in 2nd gen dyno section. You'll see what I mean.

I've done that to as much as the Rtek can let me do that, check out my thread in the dyno section.

88RXVERT

iTrader: (5)

Don’t dyno it, it will only dishearten you to find out that you spent all that money and did all that work to your S4 for a measly 4 HP to the wheels.

I was really pissed off after I did mine.

You can get more HP out of adding a cone filter then that swap.

ramses666

iTrader: (1)

I have a cone filter & a Roadrace true dual exhaust. I took some pictures... they are at the one hour photo now... I'll post them up ASAP.

Ramses666

ramses666

iTrader: (1)

ok... I'm trying to upload pics now... I must be doing something wrong... we'll see...

Ramses666

RX7Tuner.

Do you also have your secondaries opening at 4200?

ramses666

iTrader: (1)

ok try this one....
& maybe this
how about this one

Ramses666

ramses666

iTrader: (1)

I got some more pics...
This one has all the major components... you can see the bright object with the door-jamb switch.

://www.rx7club.com/forum/attachment.php?attachmentid=291883&stc=1&d=1208572 857

Here's the air compressor & rpm switches & barrier terminal strip

ramses666

iTrader: (1)

here's some more....

you can see this one is just above 4k and the 5th & 6th ports are active.

Ramses666

ramses666

iTrader: (1)

here's one a little higher rpm's

Ramses666

ramses666

iTrader: (1)

ok... here's another from the cockpit view... sorry the flash takes out the LED's indicating the status....
Ramses666

ramses666

iTrader: (1)

You can see the difference in the boost gauge in the different stages of port activation. It moves around quite a bit through out the pull. Each actuator takes about 2.5 psi to activate so at 3800 rpm there is about a 5 psi drop that recovers until the 5000 rpm drop for the VDI so the necessity of running around 10 psi total pressure for the activation system. I'm really happy with the overall functioning, but a little disappointed in the pictures... oh well. It's much more dramatic in person & especially at night. Knowing what is working when adds alot to the experience of driving... even though at full throttle you never feel any thing not "normal" just a straight on pull.

Ramses666

coldfire

iTrader: (1)

that is a decent amount of work just to see if the stages of the intake were working correctly. good job.
personally i am trying to figure out a completely electronic actuator system, which would negate the need for an air pump and can give direct feedback on operation.
i've seen it done once before, but it's not exactly simple.

Roen

iTrader: (2)

Nope, secondaries still come on as stock. The reason for this is that if you look at the injector pulsewidth, the primaries duty cycle will be halved once the secondaries come on.

ramses666

iTrader: (1)

Yeah I agree it was a somewhat complicated way to activate & monitor all the port action going on, but I couldn't really come up with a good alternative. I've seen someone trying to rig up electric actuators but didn't see it done successfully with out some fancy electrical stuff. My setup is really going to my *** to get to my elbow, but it works good and met my criteria of being adjustable and reliable and verifiable.

There was quite a bit of wiring - the gauge pod was pretty tricky to get the leds & resistors and all the wires in it - I used hot glue to hold in the leds & the gauge in the pod. There's wires everywhere in the engine bay. It would have been a total clusterF@#% if I hadn't used a terminal strip to connect all the different electrical components. I suppose some kind of kit could be made that would combine some components and eliminate some of the clutter.

I wish there was a simple way to accomplish all this port stuff, but I couldn't find any other way to really do it correctly. I basically just re-did what Mazda did originally - I removed all the factory air control & made my own. With going to the S5 intake on my S4 the factory setup wouldn't work the VDI so I was stuck. I could've used the stock airpump as an air source but mine was long gone as well as my ACV so I had to make something to work. I suppose if I was running a standalone I could've eliminated the rpm switches. I really just relocated the "rats nest" and air pump & acv & solenoid rack. Kinda funny if you think about it - taking all that stuff off only to remake it and put it somewhere else.

Maybe the best solution would be some kind of plug-n-play standalone computer and making the air pump & solenoid rack work properly to begin with, but thats tough when you put on header & exhaust and start monkeying with the stock air system. The diagrams for that thing are kinda crazy with emissions and all that split-air & relief valves & emissions stuff going on. No wonder people want to rip all that stuff out.

Ramses666

RX7Tuner.

Right, so you have the secondaries spraying into a closed tube until your ports open, meanwhile your primaries will be cut. You should have a huge lean spike from the time your primaries cut until your 5th/6th's open at 4200.

What are you doing to prevent going lean for the .368 seconds?

ramses666

iTrader: (1)

I hear ya on the ports being open for when the secondary injectors come on & the primaries are reduced. I'm happy with where I am now - it's nice & smooth. Maybe after I rebuild my old core I'll get more into tweaking it. I can see a standalone in the future, lightweight flywheel.... maybe I'll go crazy & spray it!?! I'm glad my idea worked out as well as it has so far... I've had my share of hair-brained ideas end up in the circular file cabinet. Anyone have any luck with the all electric actuator thing? I saw an old thread when searching for different ideas but didn't think it ever got finished.

Ramses666