I have a 86 rx7 and i am wondering if the actuator sleeves in the two side intake ports are needed? Because the things that turn them open has frozen up.. Just wondering if you can take them out and if it would hurt anything besides fuel mileage?

Youll hurt low end power. Its much better to have the system operational than just wire it open.



I hate seeing people who consider this a mod, it only makes you lose low end, and not gain any top end. The system isnt perfect, but its still much better than just wiring it open. Do yourself a favor and pull the manifold off, clean it up real good to the control rods turn easily, clean the sleeves all up, and put it back together. Pineapple sleeves do wonders too.

You can take off the Lower intake manifold and remove them or you can just take off the actuator motors and wire the sleeves open. Theoretically they will reduce some of your low end power, but its not very noticeable in my opinion. I am running my 88 with the sleeves removed and it works just fine.

yea mine are wired open too, and i do feel just a bit of low end loss, but its much better up top now that they are open,

since they didnt work before, its all a matter of if you wanna keep your air pump and exhaust(cat)

its not a problem getting to them cause both the motors are out the rebuilt and the old one. So I am just swapping stuff to the other. I can't get the one motor to come lose or the little things that opens the actuator to move at all. So what do I do now.

i suggest you wire them open, because if they stay closed you will lose top end power(noticable) yea, i would wire them open cheap and simple

how do you wire them open?

can I just take the sleeves out for an easy fix..cause they will be open anyway right.?

Chainsaw, how did you wire yours open?? I thought the S4 were controlled by backpressure only, no electronics.



Some people weld the acuator rods down... if you don't want to get working actuators, you might as well just remove the sleeves.

theres no reason I can think of why you wouldnt be able to get them functioning again. Get some mouse milk and soak the shafts, it's just a brass bushing that the aux port actuator rod sits in... lube it up, it will start moving again. If it's the actuators themselves which are frozen, you can probably get some from one of the guys on this forum who has removed them, or go to a junkyard and grab them.



It can't hurt to experiment here anyways, if you are curious try it without the sleeves, but if you run without the sleeves, I personally would suggest you remove the actuator shaft and the bushings too, then grind down the raised area where the bushing protruded (in the 5th and 6 port runners), fill it in with a metal filler that is fuel & heat tolerant (or have a shop fill it that can weld aluminum) and blend it in with a grinder... you should realize some improvements on the top end, over open sleeves with proper functioning aux ports even. but still a loss of low end torque.



If you don't like the results you can always find another S4 6 port lower intake manifold, every NA 2nd gen in the junk yard has one for the picking.



while you are at it with everything apart, take the opportunity to port match the lower intake manifold to the engine ports too, the ports on the manifold are often significantly smaller than the engine ports, matching them will help flow and velocity. (the same is true for the rest of the manifold junctions...)

Just get rid of them! According to Dave Lemon of mazdatrix, his dyno testing showed maximum power without any kind of sleeves more than even the radiused ones you could get from pineapple. As for low end torque, it will get a bit more sluggish under 2800 rpm. Since it is hard to keep the car under 2000 rpm anyway, it is a loss over a very narrow range. This has been my observation on both my N/As.

I've suspected something like this, but I imagine radiusing the 5th and 6th ports in the housings is better than just ditching sleeves (this is done in the popular turrentine overhaul video)... the pineapple inserts still keep the sleeve so the passage is limited by the sleeve, you cant really port it or match it to the LIM well. Is Dave Lemon's statement you mentioned available on the web? If so, URL?

Here, $10



http://cgi.ebay.com/ebaymotors/ws/eBayISAP...item=1872501557

I completely disagree with you. First, I have been there, and done that. I ran my car without the sleeves for a while. The car was on its face below 5K rpm. I have never driven a car with worse low end. It was aweful. Then I took and made an insert to go into the runner for the 5/6 ports that made it a nice smooth transition into the ports, kinda like the pineapple sleeves, but without the stock sleeve. The increase was amazing. I gained so much low end, and a little on the top end too. If you have ever lookat the port itself, the runner ends in a flat dead end a few MM past the end of the port. Thats horrible for airflow, and you can tell by driving a car like that.



I spent so much time trying to get that engine to run as good as a car with a working 6 port system. And no matter what I did, I still could not come close to the drivability of having working 6 ports. On the motor I just ported and built for my car, I made the 6 ports operational. I also made some nylon pieces like the pineapple sleeves, and did a little modifying of the 6 port sleeve so it isnt as much of a restriction. And you know what? My heavily ported motor with workign 6 ports has much more bottom end than my old stock port motor with the sleeves removed.



I think youre just wasting hp for the sake of being lazy if you wire your ports open or otherwise. A stock or even street ported motor will only lose low end, for no gain in the top end if the sleeves are wired open.



If you think its a restriction, go look at your AFM. The intake ports them selves are the best flowing part of the whole motor. With the stock ecu and manifold, there is no way to make the engien flow enough that the 6 port sleeves becoem enough of a restriction to actually have a negative effect on the powerband.

i like learning things, thanks for the info, but ill probably just remove mine, as im a lazy ****, and i dont care about low end

i used tie wraps to make mine stay open, works just fine

Mazdaspeed7,

It's interesting to see such different observations on the same subject. A guy on the 1st gen mailing list sent me a dyno sheet of his stock port GSL-SE with the 5/6 sleeves removed. His max power was 153 rwhp and 135ft-lb. of torque. If I can get him to mail me a link, i'll post it here. It did show max torque at 5k rpm rather than at 3k rpm for a stock GSL-SE but the chart showed the torque at 3k rpm to be around 105 ft-lb. which is not too shabby considering the max torque is 135. Having around 175 Hp at the flywheel is pretty nice with just a header and s-afc so it can't be all that bad!

As for dave lemons comments, he used to post on the "other" forum on rare occasions with the mazdatrix username. Unless it was an impersonator, that's where I found the comment.

I base my statements on much more than peak power/torque. If its a race only app, go ahead and pull the sleeves, theres no real need for them. BUT the people asking here dont have race cars. Street cars spend SO much of their time in the lower rpm ranges. Drivability is more of an issue than a few extra hp at the peak, while losing LOTS of torque down low where the car gets driven nearly all of the time.



People say its not bad, they just downshift if they need to go. But why give up drivability like just for a minimal(at best) gain at the power peak? its not like you would even notice the gains, but I can gaurantee youll notice the losses.

i should dyno mine both ways (i wanna dyno it anyways), one stock working 6 ports, one wired open, one wired closed, i'm waaaay to lazy to take the manifolds off, if the ports work, so you dont get that one, hmm.

time to call gd.



mike

:bigthumg:

I'm assembling my motor with no sleeves and all matched ports, S4 manifolds. I plan to get it dyno'd also with this setup, then I will try with S4 & sleeves open, then S4 & sleeves actuated... I then want to do the same steps with all S5 port matched manifolds (I already have both). Some definitive information on this would be useful. Maybe adding pineapple inserts to the mess could be interesting too.

yah, i like the pinapple inserts, they look really helpful



mike

They help a lot. Maybe only a few hp at the power peak, but everywhere else its a night and day difference. Not to meniton it makes the engine accelerate so smoothly. Definately worth every penny.

??????? -- Sorry, I have been too busy to check forums in the last few weeks --



The only comments I made about "sleeves" (I believe on the "other" forum) was in a discussion about EXHAUST sleeves !! (and even there I stated more power with a modified EXHAUST sleeve versus NO exhaust sleeve).



The 6-port engines make better low end power with the INTAKE sleeves functional (closed). Therefore, the overall power/torque curve is better when they are functioning correctly -- closed at low rpm, open at higher rpm.

which 2nd gens have 6-port sleeves, and which don't? I don't know if we're all talking about the same thing, but I thought I'd just throw this in here (pertaining to cat/air pump removal)

All 6 port motors have them. All n/a's have 6 port mtors.

oh...so if I get all pipe (no cats), ditch the airpump (it won't be needed, right?), I'll have to open up the 6 ports somehow, right? (wire them open?)

the 84-88 engines use back pressure from the exhaust to open the ports, so you can ditch the cats and the air pump, on the 89-91's they use the airpump to blow the ports open, so you need to keep that



mike

well we are dynoing um maybe during the week, or saturday

gsl-se battle!



mike

all of them do baldy https://www.nopistons.com/forums/pub...#>/biggrin.png

Edit: blah, already answered by others, ask me how to break your 6 ports =)