crossbar17

My car:
1988 Rx7 SE NA

My Mods:

underdrive pulley
high flow muffler by Greddy
test pipe cat replacement
K%N cold air intake setup
high flow radiator (Griffin)




Questions:

1. With these mods will my 5th and 6th port actuators open, or will i have to wire them open, if i do need to wire them open how do i do this the right way and what do i need to do it?
2. With no catalytic converter my air pump is usless , i already removed the pipe that runs from where the cat was to the back of the motor, if i take the air pump off do i need to plug the hose on the side of the motor or put a small air filter breather on it?
Also what about that rubber hose that runs from the back of the motor, actually to rubber hoses that connect to the piping that went to the cat, do i plug those?-(right now i havent removed air pump and plugged those rubber hoses both the big and small one)


i really need help

thanx

~crossbar

niner

you need to get or make an ACV block off plate if you remove the air pump, b/c you need to remove the ACV. most websites like racing beat or mazdatrix has them

supergoat

With a test pipe in place of the CAT your 5th and 6th ports will pretty much be useless. You'll have to wire them open. What I did was just gut my pre-cats and install a high-flow unit frmo CATCO. With the high-flow unit, I could chop my exhaust off after the cat and still have my ports open.

My opinion is on the 86-88s you need some kind of cat. The low end power lost by having to tie the ports open is not worth it. Get a high flow cat and you'll still get a HP gain, but your ports will work and you wont have to sacrifice low end torque.

crossbar17

it is to latew i already did the mod, also what will my hp gains bee?? i am lookking for top end speed and again what else should i do and what can i make the block off acv out of???


~Crossbar17

avrfan

hey guys,

first off... I'll give my 2 cents onthe 6port problem. There is a way to actuate your 6ports with an rpm switch and a small electric compressor to replace the pressure tube that used to goto the catalytic converter.
Basically, you wire the rpm switch to turn on the electric compressor which you can get from the JYD off of many cadillacs and lincolns which have air suspension. connect the hose from the compressor to the pressure line for the actuators and shabing! you have rpm activation guaranteed to work. I think you have to add in a solenoid valve to releave the pressure when the rpm switch turns off the compressor because the valves would stay open if you didn't. "NOTE: I haven't done this yet." but there's a how-to on one of the Rx7 sites but I can't remember the link.

Since were on the topic of 6port actuation, WILL ANY UNIVERSAL 3WAY CATALYTic Converter work fine to actuate the six ports? I'm wondering if the tube on the Rx7 Cats are special in some way. Like the internal design of the cat or something. Or is the factory Mazda Cat pretty much the same internally as any other 3way cat?

dave

Phu5ion

Hey, does anyone have any pics of this 5th & 6th port area. I've been trying to find some information on them but have had limited success. Pics would be a great help because then i'd know what i'm looking at.

Thanks,
Phu5ion

mprime

I think what hes looking for is more info on how to help him with what he has already done. the above post was right about the ACV block off plate racingbeat has those. If you want to know what HP gains you will see with the actuator wired open you will here from 2 sides A. its not worth them being open all the time cause you loose low end (what RX-7 do you know has any low end anyway) and B those who have done it and love it cause of the increase in the high end.

mprime

As for making the block off plate just maek sure its fairly thick so you wont get any leaks and something that will handle the heat there.

Mark S

iTrader: (1)

You would need to check to see how the pick-up tube is situated in the other cat. It needs to point into the exhaust stream. In reality, its not backpreasure that actuates the 6P, but exhaust flow into the pickup. This is what makes the size of the pickup tube & it orientation so important.

You could try putting a guage on the hose leading to the 6 ports to see what your getting. They open @ ~ 3 psi. I switched to a dual exhaust on my 87 and was only getting ~2psi from the exhaust. I tried placing pickup tubes of various sizes/locations in the exhaust, but none worked.

I finaly bit the bullet and bought a RB header with the 6port pickup already installed. It sits right in front of the front rotor directly in the side of the header. This is a straight shot for the exhaust. The pickup entrance is a little less than a half inch, which than funnels down to the size of the hose.

Its important for acceleration that they work properly. The induction system works on the basis of velocity. If the 6 ports are wired open, the velocity of the intake charge stalls at lower rpm. It then takes a longer time for the intake charge velocity to increase to the proper levels at higher rpm. With the ports working properly, the charge is already moving at a high velocity when the ports open --preventing the charge from stalling.

A lot of road racers do wire them open, but they hardly ever see rpms below 4000, so intake charge stalling isn't an issue.

Remember, total avarage horsepower over the usable rpm range is your goal for being quick. If the charge dies at lower rpm, it is only going to hurt acceleration.\\

Hope this helps

HAILERS

AVRFAN is talking about something on the order of this http://home.rmci.net/panther/6PortSolution.htm And who wanted that picture? How about http://home.earthlink.net/~burntoast...xports_acv.jpg that all copied and pasted we'd like to say there area about a dozen ways to make the aux ports open and shut especially if the air pump is left ont the car to use as a source of power(if you can call a pump that puts out six or so psi POWER). So now that I did some pasting, just why is it important to remove the acv just because you put a high flow exaust on the car??? Its just sitting there minding its own business causing no pain to anyone. God made dowel plugs to fit in open hoses. Very minor question. I have the full exaust system dual from end to end and I leave my air pump and acv on. Use the airpump for the aux actuators actuation along with a solenoid valve out of an old rx with the 3800rpm signal from the relief solenoid valve to open and shut it. Pick off the air from the back of the pump as an air supply to the solenoid.

mprime

ha that was funny. I dont really think it is important beside haveing one less thing attached to the car if its not doing anything.

HAILERS

MPRIME.. thank you. Yup. I actually do know about the weight savings and getting the clutter out of the bay. Thought if I asked someone might come up with some other reason I'm not aware of. Just having fun.

mprime

Ya I have never heard of a REAL reason myself heck I have a full open exhaust and I still have mine on. Of course I use the airpump with my mindtrain set up to open my 5th and 6th ports still.