so I got a RB header and I am going to have a exhaust shop weld a straight pipe from the header back to the mufflers. first, on the original exhaust there is that tube from the cat that goes to the actuator valves. there are two tubes connected to it, a large one (about 5/8") and a small vac tube. now I removed the air pump and stuff so as far as I can tell I will only need to hook up that small vac tube that goes to the actuators. Is that right? or will I still need both tubes? Second, I was planning on having the exhaust shop weld a bung on for the smaller tube to connect to, will there be enough backpressure to actuate the ports?

edit- this is for a 86 n/a

thanks

 

anyone?

 

your ports will not work anymore. Find another way to opne them properly.


Santiago

 

why? not enough backpressure?

 

First of all you may want to re-think the straight pipes. Your ears will thank you. Second 995 chance that you will not have enough backpressure to do anything. Third I would suggest getting a pre-silencer from RB with the H-fitting that hooks up to the split air tube and makes the ports work like normal.

Santiago

 

you wont have enough backpressure to open them. dont bother ruining a nice system like that though with a cat of anykind.. come to think of it, dont bother witha split air pipe either for that matter.

splice the plumbing off the air pump (if you still have it) and run a line direct into your port actuator diaphragms. youd be surprised - they actually open bang on at 3800 rpm!!

or, (better yet) buy a 12v air compressor used for air horns, wire it up to an rpm switch, and they will instantly open your ports just when you want them to. best setup by far.

https://www.rx7club.com/forum/showth...hreadid=121833

 

The reason I suggested a silencer is because your ears will not take much of straight pipes. Specially if he has straight through mufflers. In a week or so he will have cops following him around.

Santiago

 

I've got a header into a straight pipe into a straight through muffler that is doing practically nothing now. The only time cops have said anything to me was when i floored it through a light and there happened to be a cop on the other side, he just warned me of my exhaust being loud. It really isn't too loud inside the cockpit, especially with the windows up, turn on music and you'll barely hear your exhaust. I also have my port sleeves wired open, i would suggest you do the same if you get that exhaust on.