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...)