HAILERS

https://www.rx7club.com/attachment.p...hmentid=106358

This has been bugging me. What? That picture of how to make the auxillary ports work off the discharge pressure from the ACV.

Why won't it work as has been described???? Supposedly the pressure will appear at the discharge port at 3800 rpm and supply pressue to the auxillary ports to open them This will be true at 3800 rpm to some extent.

But here's something to consider. The ACV will discharge pressure at that hose other than at 3800 rpm.

Prove it to YOURSELF. PUt a LED on the three socket check connector. Put the power for the LED in the black/white wire socket and the other LED wire in the socket that has a Blue wire with a Yellow stripe (Relief Solenoid input wire).

Now have that LED in the cockpit with you. Just use some wire long enough to reach from the check conenctor and route it thru the window since this is temp inst. Start the fully HOT engine. The LED should be lit showing that the Relief Solenoid is energized and therefore keeping the ACV dump hose from receiving air.

Go for a drive. DO NOT JUST SIT IN THE DRIVEWAY.

Drive in forth gear at say three grand. The LED is lit. Now stomp on the pedal. The light will go out immediatley indicating the RElief Solenoid is now de-energized and the ACV is now dumping air out the large discharge hose which in turn means the auxillary ports are full open. OPEN at 3000 rpm.

Try all sorts of other rpm setting under three grand. Same result. The auxillary port will be opening long before 3800 rpm.

Now if there's anybody out there that can dispute this, let me know. IT ain't a gonna work right period if rigged like that. There.

Stanello

iTrader: (1)

I'm lost.

HAILERS

I know. You need to read how your car works sometime. Online FSM available.

Funkspectrum

iTrader: (5)

good stuff hailers....

Now if only I had an NA to mess with!

I'm still all about leaving the auxillary ports intact and stock...dunno....just me....

Stanello

iTrader: (1)

You added text 9 mins after I posted.

alexdimen

iTrader: (13)

i completely agree. i tried this and a similar method using a T fitting between the air pump and acv to activate my aux ports. this was when i had a test pipe. neither one worked correctly, so i ended up getting a magnaflow cat.

in this instance, the ports open too early. with the T fitting approach, they opened correctly, but closed later in the rpm range as air was bled off by the ACV and pressure drops.

i feel the only real way to actuate the 5/6 ports is with exhaust backpressure, with an auxillary pressure source triggered by an rpm sensor, or possibly a removed/disabled acv with the stock air pump.

lupin

iTrader: (3)

i think I am gonna just use megasquirt to activate my 5th and 6th ports.

RotaryEvolution

iTrader: (30)

the gains from removing the cats on an n/a re negligable, i recently picked up an n/a and gutted out the 2 precats since they were plugged but left the main cat intact and the car pulled very nicely and the ports work as they should. i guess if you want the extra 10hp from the full open super loud raspy exhaust then that is fine but you will need to deal with the dilemma of the port actuators.

personally i like the feel and sound of the car as i can sprint around town and not have attention drawn to myself from an overly loud exhaust.

misterstyx69

iTrader: (142)

I bought something to activate my ports from a member here(Coldfire)..he has some info in his Sig,on what the Damn thing does!..(I have not yet installed it)...if anyone is interested at all.

Unseen24-7

So let me get this straight, if you chop the cats off, the aux ports don't open??? WHY??? Is there a way around this?

importsown

I will actually agree with hailers. Although on S4's i dont think it depends on load, just rpm. Cuz i have had a buddy sit in the car and tell me the rpm when my ports started to open up (i was under hood watching and controlling throttle) and they started to open at about 2800 rpm, and were fully open by 3000. I dont believe they would actually close though, because that would mean the air pump isnt functioning at that high of rpm, which it obv is.

Syncro

iTrader: (1)

Odd... I think they are not supposed to open unless car is under load.

Are you sure?

HAILERS

This Trouble Making Thread is just about series four cars. ONLY series four cars and the auxillary ports being activated by the use of air pressure being picked off at the exaust hose of the ACV.

The ACV puts air pressure on the exaust hose of the ACV when you reach 3800 rpm. See your FSM and it says so during a *test* in the FSM.

But the ACV also dumps out the exaust hose on the ACV at other times. Times that are well below the 3800 rpm range, which means they will come open way too soon almost at random IF you have yours actuated as shown in the picture.

There's nothing wrong with using the airpump pressrue to activate them, but a rpm switch combined with a common RX solenoid will CONTROL them as to when they will open. Control being whatever YOU set the rpm switch at.

This thread is NOT related to a series five car or any series four without the ACV/AIRPUMP.

adrock3217

Ya know..while it DOES open about 800 rpm earlier then it is SUPPOSED to..it is still an improvement over just having them wired open. This will provide torque up until about 3000rpm...instead of none at all.


:-D


I'm a fan of T2 intake manifolds on an NA, aux ports are for quiters :P

alexdimen

iTrader: (13)

maybe it was just me, but mine didn't stay open using the air pump method

Icemark

again, (as covered countless times), the method works Because the air pump is not producing sufficent air pressure to open a S4 aux port until around 3800 PM.

So on lift throttle, (in which you get air dump) and in 5th gear, the posts don't open under 3700 RPM.

Again, as I have told you Hailers, countless times. TEST IT FOR YOUSELF.



Cut the Blue line in that picture, Put a pressure/vac gauge on the line. and watch when you have sufficent air pressure to open the port.

Stupied thread, so yes it is a trouble making thread.

arghx

iTrader: (3)

uhh and how many people actually even bother with running their auxilary off the ACV? How many people run with no cat yet with an ACV? I think this thread applies to like 4 people

Icemark

yep, that is true, but Hailers has had a hard on to disprove this works... .

importsown

My apologies, i forgot to mention i have an S4 and i have my pressure source the same in that picture. I actually used that picture to go by, although i ended up putting the nipple closer to the airpump. So yes in my last post that test was with air source as the air pump.

NZConvertible

Personally I think exhaust backpressure is the worst method to use on a modified engine. It works fine on a stock can because the whole system was tuned by Mazda to work right, i.e. the amount of backpressure required to open the valves occurs at the ideal time they should open. As soon as you make any improvement to the exhaust that lowers backpressure you'll push the opening point of the auxiliary ports higher in the rev range and further from the ideal point. You'll have a drop in performance in between the ideal and actual opening points.

The only way to be able to dial in the perfect opening point is with an rpm-switched solenoid valve that switches in air pump pressure at an adjustable point. That way you don't have to clog up your exhaust to get a half-assed activation, and you can tune the system (preferably with a couple of dyno runs) to get the best out of the engine. The whole point of the system is to improve flexibility and broaden the usable rev range, so it seems pointless having if you're not going to control it right.

They depend entirely on backpressure, which is purely a function of exhaust flow. Airflow through an NA engine depends only on rpm and throttle position. It doesn't matter if you're revving in neutral or on the highway, if you open the throttle right up the airflow is the same for the same rpm. The only difference is the lack of "load" at idle will cause the engine to over-rev unless you close the throttle in time. If you 6PI system is a little slow-acting (sticking valves for example) then the valves may not fully open before you have to lift off.

Icemark

See, on a stock motor, they are not entirely dependent on exhaust pressure. The Air pump uses the same exact line to feed to the cat, so when the ACV switches the air pump feed to the cat, at the same time it is also switching it to the aux port actuators.

Now granted at lower RPM, there is not sufficient air from the air pump to work the actuators, but at higher RPM and even the dump line open there is.

People mistakenly think that the exhaust pressure is the only thing that opens the stock ports, while in reality it is a combination of both the air pump feed and the exhaust pressure.

This can be very simply proven as well, by simply disconnecting the air pump and going for a drive. You'll note that the aux port actuators, will actualy be delay'd by about 300-800 RPM without a functioning air pump (dependent upon aux port valve condition).

NZConvertible

I'm not entirely convinced about this. According to the FSM (and that's all I'm basing my assumptions on), the only time split air is used is under "Medium Load (Warm)" conditions. Under "Acceleration" and "Heavy Load" conditions the ACV's relief valve is open, which blocks all air from entering the exhaust. So when you put your foot down there can be no air pump pressure in the split air pipe at all, only exhaust pressure.

But even if what you say is the case, then that would just reinforce what I said above about modified S4 engines needing a whole new 6PI control system if you want to optimise mid-range performance (where a street car spends most of its time).

SirCygnus

iTrader: (1)

you obviously dont know what your talking about. i drive with no cats, no precats, and cork sport catback, its loud, but it isnt raspy and it isnt god forsaken loud like you make it out to be. hell i drive it full throtle sometimes and my ears dont ring. hell i can still hear my music.

pfsantos

iTrader: (1)

O.K., this is definitely a trouble making thread Having said that, I'm learning more and more as I read.

I like the solution of hooking up the auxiliaries to the relief silencer hose. I am running a complete emissions system because I've had to until this year (emmisions regulations here in Ontario, Canada). The problem I've had is that the cat-back exhaust (and pretty new cat) haven't produced enough back pressure to activate the auxiliary ports. I've had them wired open in the past and noticed a lack of torque. For the past few years (I only drive a few months in the year and it was under cheapo restoration for a couple of years) I've just left them hooked up stock so they haven't been working. I'm tired of not having the top end because of them not opening.

I have to get these working again and have been searching for the most efficient/simplest way and thought this was the way (hooking up to the relief air silencer hose).

I didn't feel this was the sure fire way to have them opening at the right time, because of what the training manual says.

See http://www.rotorwiki.com/images/9/98...demissions.pdf
(rotorwiki.com has parts fiche, FSM, and training manuals)

Essentially, the relief valve is opened at other times as a previous poster mentioned. Later, another poster said yes that's true, but under the other conditions the air pump doesn't produce enough pressure to open the auxiliaries.

The trouble I'm having is that, according to the FSM (4A-39), the air pump produces 1.7 PSI at idle. So it is safe to assume the auxiliaries will open slightly above idle. Now, looking at the Training manual in the chart (page 4-38), we see the conditions which produce relief air (to silencer hose). Here's where I get confursed and may be looking at the chart wrong...

1. Engine cold or warm - Low speed, 8 seconds after Throttle open? (low intake manifold vacuum)
2. Engine cold - Light load - under 3700RPM
3. General (don't know what mazda means - maybe RPM's steady?) - cold engine air relief; semi-warm to warm 120 seconds later, applies to 1200-3600 RPM
4. Output increase - cold engine, air relief; warm engine only 120 seconds later - intake manifold vacuum high (throttle open?)
5. Others (?) - Air relief

Judging by the training manual and the fact that the air pump would be producing enough pressure above anything but idle (FSM), I think this setup may be opening the auxiliaries at times when you don't want them to open. Sorry for the long post, but if I'm going with a setup, I want to make sure it is the best one available.

Looks like the best setup may be to use an RPM switch to activate the ports, but I was hoping another sensor or ECU wire would be available.

HAILERS

****Looks like the best setup may be to use an RPM switch to activate the ports, but I was hoping another sensor or ECU wire would be available.******

No other stock wire, but the RTEK for series four non turbos has the and output wire that could do this a any rpm you want to set it at. All you'd need is a common solenoid like those on the rack and hose going from it to the large hose b/t the ACV and the airpump and the other hose to the feed pipe for the aux actuators.

At one time I did have a solenoid operated by the Relief solenoid input/output. You know, how it opens at 3800 rpm under certain conditons???? I thougt it opened only at that rpm. Later I realized that Relief solenoid gets a signal at MANY other times.

To give yourself a clue, buy just one LED from Radio Shack. Wire it to the Relief solenoid blue plug but leave the plug attached to the solenod. You could just run two wires to the wipers from that solenoid and zip tie the LED to the wipers (I suggest unplugging the wiper motor if you do this).

Then go for a ride. Make it a fairly long ride for at least a half hour or more. Drive in the Hood and also on the open hwy at steady speeds. After that ride you'll notice that LED came on/off at many different times other than 3800prm. Enough to make you realize that the only RIGHT way to make the actuators work right is to buy a rpm switch like the one from SummitRacing and use that in conjunction with common solenoid like the ones on the rack. It's not that much money.

Even better buy two LEDS. One going to the Relief solenoid and the other to the Switching solenoid. Buy two seperate color LEDS to avoid confusion as to which is going on/off.