i know that the s5 motor auxillary ports open from the pressure of the air pump, but just to clear things up would my ports still open if i removed the cat and capped off the line that went to the cat converter? wanted to order the RB headers but didn't know if i still needed to order the pre silencer or something for my ports to still function properly. i just want to run a dual srtaight pipe back to the mufflers from the headers.

 

I just did exactly that. I replaced my cat with a Racing Beat downpipe/ presilencer and removed the pipe that went to the converter. I was curious about port actuation as well so I decided to put a "t" fitting on the hose going to each actuator and attach a vacuum/ pressure gauge ( I put the gauge under the driver's wiper arm temporarily so I could watch it while driving). It read almost 2 psi at around 4k and above. Here's a tip:
If you want to check your port actuators to see if they actually open, find the solenoid on the rat's nest (brown connector). Disconnect the hose that goes to the solenoid from the air injection pump. Also disconnect the hose that goes from the solenoid to the actuators and connect the air pump's hose to it (this bypasses the solenoid to test the actuators). Use a flashlight and watch each actuator plunger move while you snap the throttle. Each actuator plunger should move about an inch and then return completely at idle. If not, suspect binding port sleeves, bad actuator or a cracked/ disconnected hose on the rat's nest. I probably should do a writeup on this with pics.

 

will do thanks

 

I found that my actuators weren't working at all before I did my exhaust mods. I had a split hose on the rat's nest that went from the solenoid to the actuators. I always wondered why my engine seemed to "run out of steam" after about 6k. Now she happily revs strong all the way to 8k. WOOT!

 

You might check the forum for threads on the RB headers. I have read that if you go with those the sound is very loud. If you like it loud, go for it. I chose the RB presilencer/ downpipe because it's much quieter. The presilencer is straight0through, but it is lined with stainless steel wool which changes the exhaust tone a bit. Just my 2 cents.

 

i like it loud which is why i made a tread earlier abought straight piping the exhaust to two yosh mufflers which also have the steel wool packing

 

I'm pretty sure they are only supposed to work under load. In neutral, the actuators won't actuate. Thats just my observation. To make sure mine are working, I have a small LCD screen and an infared camera I'll be installing temporarily. That way I'm positive. But, I'm a geek.

 

All I meant is that you can temporarily bypass the solenoid and check to see if they are moving without using a camera. Then re-connect the solenoid and "tee in" a vacuum gauge to see if the actuators are getting the pressure signal from the solenoid while driving, then you know they are working when you remove the gauge.

 

Well, I already had the camera/lcd..... I didn't buy it for this purpose.. I guess thats kind of how it sounded. LOL

 

Although the camera idea sounds pretty cool.....you could see it "live", maybe burn it to a dvd and share it with all your friends

 

Well, I was thinking of posting it to my wiki and calling it good.. but clearly you have bigger plans.

 

Have fun with your exhaust and update us. A sound clip would be great as well.