Hey guys, i read all the time about people wiring their 6th ports perminently open, and i'm elbow deep in a rebuild right now, I was wondering about simply removing the 6th port sleeves all together.. is this a wise move?

thanks

 

If your engine is going to make that kind of power where it is not needed then yes it is a wise move, if it is a stock or even a stage 1 streetport then no keep the sleeves in and tie them off or keep them working.

 

That's what i was looking for, I'm only going to be doing a mild (stage one, [i]possibly[i] stage two stree port... I'll probably just end up tying them off.. . thanks for the help!

 

Tying them off will only make you loose low end and not gain any high end so FIX them up so they work properly.

 

For once he's right. Keep the port valves operational unless you are doing some extreme porting.

 

Come on Aaron thi shas to be like the third or fourt time

Get some pics of the port job that might help people in making a better decission on the port size.

 

Good point.

 

Alrighty then, functional it is... But isn't having a functional engine sorta... i dunno... boring

 

I removed my 6 ports and grinding it all down when I was NA and the loss of low end wasnt very dramatic. Top end power appeared to increase

 

I hate to go against the trend here, but I noticed a marked improvement in the top end of my power band when I took out my sleeves alltogether and kept everything else the same...
Didn't notice any difference in the low end.. possibly because my car doesn't spend long in the sub 4,000rpm territory

This is when my 6-port was N/A of course, I'll bet theres an even bigger improvement to taking them out now that its force fed.

 

I took mine out and ported the manifold, but haven't put it back together yet. One thread I read, Mazdaspeed 7 said he noticed gains in all bands, so thats why I did it. We'll see how it works out.

 

Mazda made this system for a reason. They still use it on the 6spd RX-8. There are three basic reasons: Drivability, fuel consumption, and Power.

When your stock you don't reelly notice much if they don't work. When I got my true duals I had just started to notice my ports stop working so I bleaned them out and it was a BIG difference from WORKING to not working. One had been stuck half way open and the otherone just couldn't open at all. I noticed a bit more low end with them working since BOTH were closed now providing more tq down low. I don't think all of us drive above 4k rpms ALL DAY! which is the only situation where it won't make a difference.

Fuel consumption is also a factor because with less tq(wired open or taken out) you waste more gasoline in daily driving at lower and mid rpms. Also when your at or above 4k all four injectors are firing so your fuel consumption goes through the roof.

Power in all RPMs is important to me because I don't drive at 4k like I already said the only time I am above 4k is if I am in a HURRY or on the highway doing 100mph.

If you have a turbo'ed N/a then that would make up for the power loss but the 6 port design is inferior to the 4 port when dealing with forced induction so meh.

Santiago

 

wow, lots of good info here Tough choice, but i think i'm going to go with the whole "properly repair them" trend... i wouldn't mind all the low end i could get

 

Just as 1987RX7guy said, the functioning system works better. Period.

If you do not care about low end power or you plan on just keeping the revs up all the time, then its fine. Bottom line is that it is your choice. If you take out the sleaves please take out the rods too. They are an even bigger restriction.

 

As stated, you'll lose mid range torque, and not gain anything more on the top end. There's no advantage.

 

If your car is 100% stock then yes, I would agree that the actuated 6-port system is of marginal bennefit.


You had more power with the zorst dude, of course the difference would be more apparent, its a percentage gain between them not working and working, they don't add a constant ammount of HP or anything.
I'd bet my left nut if you took out your sleeves with that exhaust you would have made another just as apparent increase in your high rpm power band.

Secondary injectors also only come online if your at or near WOT, they're not just RPM activated...


Well thats fair enough for you, I was just adding my input on how it changed my car, I for one am not putting the sleeves back in my motor...

No if you had a turbo 6-port without the sleeves the extra flow would allow more power, it's not the 'turbo making up for lost power', there would be less with the sleeves in there working or not. So going by that statement you have alot of experience with 6-port turbos yeah? care to elaborate why they're 'inferior'?

 

S4, NA, all emmisions and air pump removed. I was under the impression that if the air pump was removed then there wouldn't be any way for the actuators to work. So I removed them, and with no loss of drivabillity and a gain up top. then my car broke...

 

That's a good point, Makenzie71. There's no reason for me to put the air pump back on, therefore the actuators won't work anyway, correct?

 

ditto

 

S5's use the air pump not S4's. Your ports were probably stuck if you noticed a gain up top.

Santiago


If 6-ports are better than 4-ports at forced induction then why did mazda use the 4-port design for all the TII's and for the REW?

 

I know...but the S4 used them for the actuaters just the same. My port's were beyond stuck...however...

 

no makenzie the S4 only uses the air pump for the catalitic converter NOT the auxilary ports.

 

then what operates the sleeves?

 

backpressure routed through a small line that comes off of the catalitic conveters(pre-silencer or headers on aftermarket systems) to two small actuators which have arms that rotate the sleeve rods.

Hope that helps. I think it is 3-4PSI that is needed.

 

hmmm...learn something new everyday. Didn't matter anyways, then, because I had my cat's removed and made my own header...12lbs!!!