As the title states... I want to run the stock S4 twin scroll (Yes, I am strange). I have 3 PWM outputs not doing anything. Which is the best one to operate the solenoid? Stock, it kicks in at 2700RPM I think.

 

You're not strange for wanting the same low end torque that Mazda designed the car to have. I don't mess with E6K's really but I don't see why it would matter which one you used.

Make sure you have the control logic correct. The solenoid is engaged when one of the scrolls is closed (low rpm), and then it turns off at higher rpm. It's 2700rpm from the factory.

 

I understand it uses the solenoid to allow vacuum to reach the actuator, and hold it "closed" under 2700rpm. Once that RPM hits, it releases the vacuum. I'm wondering what the best way to control this is. A simple output for a shift light could work, but normal driving around 2700RPM it could be trying to constantly open and close it. I'm thinking I need something that would open at 2700 rpm, but give me some buffer time/rpm-wise if it drops underneath just a tiny bit.

 

bump... for myself or anyone who cares... Looks like the dual intake valve control (DIV) is perfect for the twin scroll. Page 93 of the e6k manual. On RPM and off RPM are the only 2 settings. Perfect

 

that should work. i know the factory opens @2700, but i'm not sure if it closes @2699, it would seem like a 100-250rpm buffer would be perfect.

you should also play with the opening RPM, i know once you open the exhaust up, 2700rpm seems kind of late.

 

It wouldn't surprise me if the solenoid turns on and off at 2700rpm from the factory, and the mechanical properties of the actuator determine the hysteresis. Basically the design of the actuator may result in an intentional design or a buffer/threshold to accomplish the same thing.

 

Do you think I should lower the activating RPM? I'm actually going to be running a hybrid (BNR) with a racing beat 2.5inch DP (and will make a new exhaust to go along with it). This may seem like a waste of time as many people rip this system off. I want to try it though because I am weird, and I like making things function

Winter is here though, so I won't be doing this till april next year at best.

PS
noticed the stock solenoids are all the same. The difference with the twin scroll solenoid is that the inlet port and filter are opposite the 3 other solenoids. You can actually pop the little filters off and swap with the opposite inlet if you need to.

 

people remove the s4 twinscroll because they purchased an s5 turbo (which doesn't use it) or because they don't understand how it works/why it's important or because they are too lazy to make it work.

 

well worst case you can just wire it open, but if you have the PWM, its fun to play with... i've driven a couple T2s with working twin scrolls, and open exhausts, and it seems like when the thing opens, you get more power, which might mean with more flow it should open earlier, easy to find out!

you should really consider a 3" DP, it makes a huge difference, after the DP 2.5 seems fine

there are 2 solenoids, one is straight thru with no power, the other takes the 90 degree bend with no power. so there are 2 part numbers.

 

I have a 3in DP but it's old and crusty (currently on car though running an old greddy turbo setup). I got a good deal on the racing beat piece and it's in perfect shape. I want to buy the presilencer too because right now it's a full 3 inch single and it's loud.

if you look close at all the solenoids, they have the same number stamped on the side. You can literally pop the filter off one end and put it on the other if you want to change it. Either way I got this part figured out.

Thanks