Question is- when header is installed and air pump is removed, how do the 5th 6th ports open? Is that where the electronic opening of the ports have to be done. Need help, installing RB header soon, thanks in advance. Greg C.

 

no. they stay shut I think. you'll need to find another way to open the ports.

 

You'll be fine as long as you leave the air pump in. The S5 opens the ports using the air pump and ecu unlike the S4 which uses exhaust back pressure.

 

when you install a header is the air pump not used anymore?

 

Good point I wondered that myself. I installed a straight pipe and left my stock manifold. When I asked a guy the same question about problems with the 5th and 6th opening up correctly he said as long as you left the air pump in I'd be fine. But I hear you won't have problems with RB headers as opposed to cheapo's.

 

danke....sorry i'm new haha

 

air pumps feed air into the cat which you will still have if you install a header. the cat is further down the exhaust.

 

ahhh, here's the thing....i'm getting a custom one made to extend to the y-pipe...replacing the cat's place

do i have problems now?

 

O.K. let me explain more... I am planning to install a RB header with no cats, straight pipe to y-pipe to dual mufflers. I am aware of the fact that my air pump pumps air to the various parts including the 5th and 6th ports- this is my concern. As previously stated, in most cases when installing a header, the air pump becomes basically obsolete and can be removed. However, since my S5's aux ports operate off pressure produced by the air pump- what do I do? Do I have to install a electronic switch to operate the aux ports? Surely someone is running a header on a S5... Any help welcome. Thanks in advance.

 

the aux ports function is series dependant. honestly, i dont know how they function exactly. my system was messed up, removed, and never fixed. mine were simply zip-tied open.
this subject has been beat to death so many times, so there should be plenty of threads you can find and read through. read about how your aux ports function and how to make them function properly when you remove or modify certain parts of the car.

 

guys, guys, guys, you only have to worry about 5th and 6th port openings with modded exhaust on s4's. The s5 used the air pump with a COMPLETELY INDEPENDENT LINE to the aux ports to open them. As long as you have your air pump in and WORKING, you are okay, even if it is unplugged from the exhaust all together.

 

Yeah I understand that Falcoms, but I was wanting to have the air pump removed to free-up that little extra HP. I am guessing then that if it were to be removed then, I must use some type of electronic relay switch like I've read about on the forum? I suck at electrical is all that I'm worried about. Thanks.

 

leave the airpump in, youll gain 1/4hp, if that from removing it and it doesnt weight that much...port the intake manifolds, its a much easier thing to do and youll see real gains from it. making an electronic switch to activate things is just going to cause problems in a few months when it breaks. if you halfass something then it wont last long at all, some switch made from gardenhose and plastic is just asking to cause problems later. save yourself money and time and leave the thing in there.

 

Use the RB header/presilencer combo for the S4 and you can remove the air pump just like in S4's. Thats how I am running my S4 true duals on my S5. They work sweet!

Santiago

PS- Love the feeling of the ports/vdi opening up

 

How does the S4 system differ from the S5? Do your ports open from exhaust pressure on the S5 running S4 true duals? Thanks

 

If you are installing a header and removing the cats, oviously you do not care about emissions. I have a 91 with the RB and presilencer. Got rid of the cats, air pump, actuators and wired the 5th & 6th open (actually I removed the sleeves) but it is up to you how you want to do it.

 

Yeah I know that can be done, stacher, but I believe that also hurts low end power-which I don't want. Thanks