I tried mine 25hz. Wastegate was fluttering or something, now running 40hz with ectune.

http://www.youtube.com/watch?v=gJMUtrW9YwE

 

There are brackets available for the 3 port MAC's here: http://www.circuitse7en.net/fantcube...d&productId=24

I don't see any for 4 ports though.

I think if you go too high on the frequency the valve won't be linear at the extreme ranges of duty cycle. Of course too low and resolution/step response is slow.

 

The resolution of the 4 port stinks. I dont see a rise in boost above my 5psi wg spring until 50% duty. Then I get 15psi increase with only 60% duty. It makes it really tough to control with such little resolution. 70% duty will boost uncontrolled and hits my boost cut at 30psi. Im switching back to a conventional 3 port.

 

I would think you should get better resolution>?

 

I had the 4port installed with s300 and 7lbs springs and it wouldnt allow me to hold 30+psi at the track. Swaped it out with 10 pound springs and back to a 3port and its holding better now.

What would cause that issue?

 

Sounds like I had the same problem. I was orginally on gear based but then my tuner changed it over to duty cycle and still had the same problem. Everytime I would change the duty cycle i noticed no difference in boost. 4 port FTL

 

Well hold on. What duty cycle was required to make 30psi with the 4 port? And at that pressure I would expect that you would need to ramp up duty with rpm to hold the same pressure. Thats not an EBC problem, thats a pressure ratio problem.

Are you saying it holds 30psi to redline at a steady duty cycle now with the 3 port? If thats true thats amazing.

 

stupid question:
when you guys mention duty cycle your referring to the duty cycle of the boost solenoid itself correct?

im just trying to get a better grasp of understanding my s300 and smanage

 

yes. the DC that the pulse gives from s300...

i too had my share of misfortunes using 4port....

its just too sensitive when the boost starts to react when you increase the DC...
you can get as much as 5psi @ 1percent duty cycle added...its just crazy...

i'm switching back to 3port, and tune with dual solenoid (AEM).
it will not be straightforward, but it sure will control the boost that i want..

 

is anyone running the dual 3 ports and how is the resolution with that setup ? I was going to run the 4 port but thinking ill stick with my 3 or go dual 3's ?

 

Can someone shed some light on my setup..
I have a single 3 port, with twin 44mm gates..

with two 5psi springs, I could only hold a max of 19psi with 99% duty cycle on S300.

Changed to 12.7 springs in both and I was only able to increase to 26psi, I believe it was around 70% duty. After that, It didnt respond anymore to the increases in duty cycle.

Is there something that I should be aware of? I know the 5psi springs were small and 19 was probably the max, but with the bigger springs, why was I only to get it to hold 26?

Why did it stop responding to increases?

 

Good question. Yes i kno this is last years thread but im stuck at 32psi on 97% duty. I dont kno if its my cams that have too much overlap or what. Running a 12.7psi spring in a 66mm gate. Need to make 40psi of boost without Co2

 

im actually looking into these 4-port controlers as well

 

I bought 1 (2) days ago but these bitches said its gonna get here in 3 wks... WTF they must not kno im impatient as fuc. A Do-Work ill let you kno how it works if i install it before you get yours...

 

Most 3 and 4 port Mac valves are 5.4 watt. For a given wattage the 4 port valves need to run at a lower frequency than the 3 port valves to be linear over the same range of duty cycle. So a 3.5 watt 4 port is best run at about 10 hz vs 20 hz for the 3 port. This is because the stroke on the 4 port is longer. See here: http://circuitse7en.net/page26.php (scroll to end of page)

Those who swap out 4 ports in place of 3 ports without checking/lowering the drive frequency, frequently (lol) run into control problems.

Hope this helps.

 

I've been told you want the 4 port for cO2 boost control. Other than that the 3 port should work just fine.

 

3 port is the standard valve to use with single port wastegates. (uni directional control) Single port wastegates do not benefit from a 4 port in normal practice.

4 port is for cars that need the widest boost range. 4 port allows a lower w.g spring to be used for a given boost pressure because it can apply boost pressure in the closed as well as opening directions (bi-directional force control of the wastegate valve).In one position the diaphragm force is assisting the spring force ,in the other it opposes the spring force. Used on cars that need to run very low boost for traction in the lower gears, but also high boost in the upper gears. Boosted large displacement cars especially, or FWD with 2 step or anti lag etc (have the ability for high boost off the line).

4 port is for taking advantage of the boost control range that DUAL port wastegates can provide.

 

i have 2 4 port valves i thought i was going to use. one is in the box, both unused.

 

running two 3-port solenoids works well, I was able to go from 5 to 35 lbs of boost. Rule of thumb for a single 3-port is you are able to achieve 3x your wastegate spring pressure.

 

more like 4 times not three. Im running a 5 psi spring in my godspeed 44mm RS wastegate with a 60-1 turbo and I can get it to hold at 22psi max without tapering or peaking. after 24 it does start to taper down though. I have a old mac solenoid (3port) connected from the turbo compressor to wastegate. I Noticed that when people use fatter lines or don't connect it right off the compressor than they boost far less. With my old wastegate on friends car (turbosmart) it now makes 3.8psi when on my car it made 7.2psi. the only difference was the size of lines and plumbing locations

 

A lot of these issues with both 3-port or 4-port is application... The wastegate is constantly fighting against exhaust pressure, so whether the solenoid works well or not really depends on your turbo setup.

Differences like log manifold, shorty tubular, topmount; wastegate size and then a turbo that is "flashing" up to its peak efficiency range versus a turbo that is about to choke on the compressor map will exaggerate these extremeties. One setup will require lots of duty cycle to get a small boost increase, while the other will need barely need any duty cycle. This is why some people can get 3x the springbut some only 2x spring out of a 3-port.

The difference in tuning can throw things off; hence, cars on race gas tune that run near 20 deg BTDC of ignition timing has much better control over boost, versus a car that is on pump gas with richer and conservative timing. Many instances, a turbo setup that boost creeps can be fixed with advanced timing and leaner AFR's. Just check on your tuning and see if all your boost regions (5 PSI, 8 PSI, 12 PSI, etc.. tables all have nice aggressive timing values and no rich dips). This has been covered a few times already on the forum so its just a quick recap.

I am just throwing these references up so that guys don't have to go back and forth with solenoids trying to solve some issues that could be mechanically related. Look at the your turbo setup first and see how it runs with just base wastegate pressure, and swap through a few key springs with pressures you plan to run each gear (e.g. 5 PSI, 12 PSI, 20 PSI), and you will get to see the granularity of your boost levels on just mechanical operation alone. From there, you will have a good starting point and know where your setup needs the most resolution based on whether your boost creeps, tapers, spikes, etc.. at different boost levels

In most cases, whenever I am about to max out a turbo, the 4-port always does well. Dual 3-port configuration is literally identical to a 4-port in resolution.

 

For the valves themselves, the 3 port remains linear over a wider duty cycle range given the same drive frequency and the same wattage vs the 4 port series.

To get the same linear width out of the 4 port the wattage needs to be increased OR the drive frequency needs to be lowered.

Data on this here: http://circuitse7en.net/page26.php (at the bottom)

Some people try to run the 4 port 5.4 watt at 31 Hz, that is not an ideal situation. The valve trends to on/off behavior with little "variable" flow control in the middle duty range. See link above.
It can work, but not ideal and can lead to boost control headaches and on/off behavior. Lower the drive frequency or use the higher wattage version.

 

So if that's the case what valve do we want to run?

 

"High Power" Mac valve? 5.4watt is the highest DC valve they offer in the 35/36 and 45/46 series. Confused.

But that article is interesting. I will try lower frequency again but I do believe I tried lower before and it generated less boost at a given duty cycle but I cant find my notes on it.

 

I have a mac valve in my hands right now that is 12 watts.36 series 3 port. The valve is custom made by mac as far as the valve body goes, but i don't think the wattage is custom, since we normally use the same 5.4 watt version everyone else does.