I have a 1991 Convertible with the mods listed in my signature. Would removing my actuators and wiring open my six ports make any sense or show any gain in horsepower? Thanks for the collected wisdom of the rotary gods.

 

https://www.rx7club.com/forum/showth...threadid=45616

 

Yeah I read that, but my friend has his wired open and you really can tell the difference. That post really does not answer my question, which is why I asked it in the first place. Thanks for the info though.

 

Do you know for sure whether or not they are operating right now? I know I did not answer your question. If you know that they are working for sure right now, why not just take the thirty minutes and wire them open temporarily to see what you think. At leat this will bummp yu to the top again.

 

If I understood the thread correctly,

I think that what that thread says is that you can open up or wire open the 6 ports on a series 5 13B, however you will loose HP up until around 6000 RPM where you will break even and start gaining some HP at 7000 to 8000 RPM.

So where do you drive? At 3-4k RPM or 7 to 8k RPM?

Frankly of the two RX7s that I have drove with the 6 ports wired open, they were dogs until you ran them up in RPM. I think that alot of the HP gains that people percive on this mod are mostly related to the "I did this on my car today" syndrome. This is of course comparing them to a couple normally running tuned correctly NA cars. Perhaps the percived change for others were the difference between stuck closed 6 ports and wired open 6 ports.

I suppose tuned with a Haltech, the 13b could run better with the ports wired open, but using the stock ECU they seem to just run too rich.

 

Hell Yeah you should wire them open. I wasn't sure if mine were working completely and so then i wired them open. I could really really tell the difference when i hit around 5000 rpm. The car just surges forward and pulls like mad until about 7500 rpm. I guess if i think about it there was a small loss in low end but who cares, when you are driving at 3000 rpm you aren't trying to go fast anyway.

 

That is exactly right. I tried it and noticed the same results. I've since unwired them and have been working on getting them to work "correctly." I've used a lot of lubricant, and have manually moved them many many times in attempt to free them. Doesn't hurt to try and decide for yourself though. It doesn't take long at all. . .

-Derek

 

What and where exactly are the 6th ports, and how do you know if they are operating correctly?? I would like a description of where exactly they are and what they look like, so if you could give me a little info that'd be great. Thanks.

 

Actually, the 6-ports open at 3800rpms, so your only loosing low-end torque until 3800 ropms.

Rxmfn7 - 6-ports(5th and 6th ports, Auxillary ports, all the same)are another set of ports that are activated at 3800rpms. There is an actuator with a rod that extends and retracts. Attached to this rod is a little tab that sticks on the lower intake manifold. Attached to this little tab is another rod that extends into the intake manifold and intot the engine block. Attached to this rod is a cylinder with a hole cut into it. As the actuator rod moves up, it turns the tab, turning the rod extending into the intake manifold, and therefore turning the cylinder with the hole cut out of it. As this cylinder turns the hole matches up with the auxillary ports in the engine allowing more airflow. When this opens too early, or if they are wired open at all times, you will loose a little bit of low-end torque.

 

Oh, ok. Well then is stuck ports the reason for the common 3800rpm stumble?? And also there is something I dont quite underatand. If the ports are open after 3800 rpm anyway, and you just lose power below that if they are open, whats the point of wiring them open?? Since they would open anyway after 3800rpm?? right?? Could someone explain why this gains high end power when they sould be opening then anyway??

 

Well, im not sure of this, but when the accuator pulls the arm down (or up, depending on the model) it only goes so far (i noticed this on my GTU when i got the ports "working" again) and when you wire them, they are turned ALL the way, like maybe about 1/8-1/4 of an inch or so, so im guessing the accuators dont open the sleeves all the way. I may be wrong, but thats just what im guessing. anybody?

 

The whole point of wiring them open is because on most of our cars the 6 ports are 15 years old and not working properly. This usually means that they are not opening all of the way or at all. By wiring them open, you are making sure that they are fully open when you are in the high rpm range. This ensures that you fully utilize your 5th and 6th ports. The reason that my car is faster because i wired them open is because they were probably not opening all of the way before. The ideal situation would be to have perfectly working 6 ports and not wire them open. But this requires taking off the intake manifolds and etc etc. So the quick and easy solution is to wire them open. It makes sense if you think about it.
Craig

 

i guess i dont make much sense i took my manifolds off and cleaned the hell out of everything and got my ports working, and hooked them up to my air pump and got them clicking on at around 3500-4000 rpms. Alot of work, but i wanted to see which was better, wired or working, next, i may try removing the sleeves all together, who knows.

 

For most of you, working 6-ports is best. For some people it isn't. On series 4 engines, the rod retracts to open the ports. On series 5 engines the rod extends to open the ports. There are a couple of reasons people either wire open their 6-ports, or remove them completely. The 6-ports tend to get stuck, having them wired open or removed is less of a hassle and/or headache for some people. Some of us race our cars, and rarely see below 3800rpms, so they are deemed pointless to us. Also removing the 6-ports actually gives a little more high-end power then having them wired open, or normally opening. Because there is less turbulance due to removing the rod, and cylinder that is in the intake stream. On series 4 engines, people have to worry about exhaust mods making there 6-ports not opening. Rather than worry about what exhaust mods can be done, some people just wire them open so they can do whatever the like with their exhaust. Series 5 engine actuators work off of air supplied by the airpump and controlled by the ACV. A lot of us like to remove the airpump for more room in the engine compartemnt, less weight, and to get rid of one more pulley parasitically robbing our rear-wheels of horsepower. Also the ACV can be removed once the airpump is removed for more space in the engine compartment. Without these components, the 6-ports will not function, so once again they get removed or wired open. Hope this clears up some confusion.

 

So on my 1991 car, would the rods pull or push? So I can test to see if they are working or not. It is a remanufactured engine that went in just last year so I would assume that it would make sense that they are still in perfect operating condition. Thanks for the help.

 

On the 1991, the rod pulls upward when enough pressure is applied to the vacuum hose connected to the actuator. When the rod is all the way up, then the 5th and 6th ports should be opened. As explained before, the main reason for "wiring" the 5th and 6th ports open is mechanical failure. When carbon deposits form on the 5th and 6th port sleeves, it makes them harder to move and sometimes leads to the cessation of their operation. Like I mentioned before, I did notice quite an increase in top end power with my ports wired open (obviously if they weren't working right, there would be a fairly large difference). I have to admit, though, that with them wired open, I did lose some of my low end power. In other words, I'd rather have them working right than working halfway right. Just try wiring them open, and if you like it, then leave it, and if not then cut the wires and let them stay as before. Maybe you'll decide to get the Pineapple racing port sleeves too.

Good Luck,
Derek

 

Hey... I have excelent low end and is still very streetable on my 89GXL. I dont have the sleeves pump actuators and wired my vdi high. See my new post about vdi. But i also took the belts off and lost about 100 pds so that kindof made up for it. But u some poeple will make u think that its not streetable. Its very streetable even at under 3800 rpms wich is were i drive at.

 

Just to clarify a bit. On 89-91, the rods PUSH up, not pull. 89-91 actuators work on air pressure, 86-88 work off vaccum and they PULL down.

 

Well SORRY. I did mention that they work off of vacuum pressure, and if you want to get technical about it, then originally we were speaking about "wiring" 5th and 6th ports, so actually you would be PULLing the rods up, am I right? J/k


-Derek

 

Leave them alone.

My car has them working properly and at 6500rpm where they snap shut my cars surges ahead nicely.

 

Hehe...yes, if you have a midget sitting in your Series 5 engine compartment with a little handheld tach. operating your sixports, then he would be PULLING open the 6-ports. I forget sometimes, how many people go this route for 6-port actuation.

 

Yeah, my little midgets are gettin' lazy. I'm thinkin' about replacing them. I think it may just get a little hot under there for them. That, or the exhaust is gettin' to them. . .

 

Hehe...carbon sealed 6-ports, lazy midgets, its all the same.

 

There's those damn thread pirates, they seem to be thick as sand fleas these days!

But seriously, thanks for all the information.

 

****. That means my six ports aren't working. I removed my those components, while using a midpipe. I noticed a big increase in power. But my six ports aren't working then. U know how there is a hose that went to the stock cats - to apply backpressure to the ports. Why would companies sell midpipes and headers without a spot for this hose?
I heard that the six ports only open when the car is in gear, is this true?
If so how would i test if they are working?, which i still think they are.... and why would anyone ever just wire them open? why not gain hp, lose weight by taking them off??