For 40-50psi boost configurations, what solenoid and spring setup is everyone using?

72mm, t4 1.25ar, twin 38mm gates (switching to twin 44s)

I have a 7lb spring in each gate, 4-port solenoid, and boost by ground speed on aem v1.

The 4-port is insanely touchy. 40-50% duty cycle is basically the range spectrum for 20-40psi, and as such, the resolution is really touchy as 1% is really volatile and equates to roughly 4psi jumps for us.

What is everyone else using? Can i get away with a 10-12lb spring and single 3port to 45psi?

Two 3-port solenoids has just as bad resolution as 4-ports correct?

I have a boost leash on c02, that can get me everything i need, but for now i want everything consolidated to just the aem box.


What boost solenoid and spring configurations are most using for their sfwd setups?

 

If the resolution is your main problem just turn down the frequency. A lower frequency will open the tuning window up so you can have better control. If your using manifold pressure to hold the valve down on the gate it will be difficult to get a 3 port to reach 45 lbs even with a 12psi spring, using the 4 port or two 3 ports bleeds pressure off the bottom of the gate and decreases spool time.... good luck

 

Not sure if the newer AEM boxes allow for frequency adjustment, but basically on the AEM V1, in terms of usable frequencies, I can use 31hz (where its set now), or 15hz.

Would the solenoid still function at 15hz, and provide better resolution than currently at 31?

With a twin 3-port wired parallel to same power/ground, in terms of functionality, the dual 3port and (1) 4port are technically doing the same thing as one another, right? So no significant benefit over one or the other without to control each solenoid individually in the ems?

If using 15hz frequency for better resolution, is there any benefit to using a stiffer spring than the 7lb that's in there now, or should I leave it as it should reach my target boost?

 

Dual 3 port will give you a much wider range of adjustability vs a 4 port and like a 4 port it should allow you to make as much boost as you need even with small
Springs in the gate(s)

 

@turbo-ls,

Are you using a dual 3-port with a single dc% map that controls both solenoids?

I can order 2 3-ports and wire them parallel to make it plug n play so itd be easy to swap between that and 4port.

Would a 5-7psi spring suffice in getting me to 45-50 if i needed? 7lb gets us 34 @ 50% dc, so logical answer should be yes, but its mostly us just learning as we go.

If 5lb springs would get us to 45+ still, and offer better resolution than the 7lb, then id like to try the 5lb and twin solenoids and see if we have better luck.

 

Essentially when you use dual 3 ports or a single 4 port eventually you cut off all boost reference from the bottom port and all of it goes to the top port so really it should be able to make whatever the turbo is capable of doing. On a single 3 port I see 35 pounds out of 9 pound springs. Switching to dual 3 ports because I'm going to need 50+ pounds and don't want heavy gate springs. And yes you use a single output and duty map to control both solenoids in parallel

 

Ideally you want to have two separate tables. One for each solenoid. Use the first 3 port for good control out of the hole then bring in the second at a certain speed, manifold pressure, turbo rpm, whatever....

 

Hey Chris, with regards to your comment, what about for a 4-port?

 

If the ecu can provide that then yes it's ideal but dual 3 ports in parallel will accomplish what a 4 port will do with more adjustability if you ecu doesn't have that option

 

Precision 46mm gates come with 1.5, 3, 6, 9, 18lb springs

Gunna try the dual 3port and 4.5lb springs and hopefully thats all i need.

Could i technically run the c02 to the solenoids, and let the solenoid regulate pressure needed? I have a full 2.5lb bottle woth regulator i might sell with a boost leash. I wonder if its of any use though to me with the aem v1

 

Dual 3 ports wired parallel will yeild the same results as a four port... they both duty at the same rate and 2 3 ports and the 4 port do the same thing as far as bleeding the bottom of the gate and applying pressure to the top. If the v1 doesnt allow for variable frequency (which im pretty sure it does) than try the 15hz it cant hurt anything. If you really want to try two 3 ports give me a shout we have them in stock and i will give you a stellar deal just remind me who you are.

 

My personal car is on co2 i can control 14-58psi, i still have 2 3ports wired parallel but it was vecause i was to lazy to take one off after i stopped using manifold pressure. Co2 will be more responsive but is unnecessary unless you are trying to make alot of power at the kind of altitudes we are at.

 

This is more just a comment / question for CO RaceFab. How bad does it decrease spool time with the 4 port or 2-3 ports? are either or the same? or does the dual 3 port slow the spool even more. I switched from a single 3 port to a dual 3 port because I wanted to hook up 1st gear on the street but be able to put down 700. man I thought my turbo was broken lol. it literally added like 1000rpm spool time and it came on very linear. is that how bad it is? is there a way to get around that? or is the 3 port the best option and just accept never hooking up 1st and 2nd.

 

My main gripe about the 4 port is lack of resolution and sensitivity. It's not very good for control down low. That's due to the bleed of the reference port. Name of the game is getting these cars out of the hole and not shake the tire or overpower the track.

In the beginning of 2015 I started using the AMS-2000 pro boost controller paired with my Motec M150. It's by far the best investment I have made to date. Best boost controller I have ever used, hands down. Also switched to Co2 for full fine control (+/- 0.1psi) from 7psi to 60psi.

 

Damn thats some good resolution!!!

 

It should make a difference in spoil time. It's allowing full pressure to the bottom as a straight vacuum line would when not activated and then bleeding that off and adding pressure to the top port as you increase duty cycle so should react the same way a single 3 port would. Just manipulate the amount of duty to get your desired boost curve

 

Imo both setups without co2 react identically... but you have to think about it like this with co2 you can apply 100psi to the top of the gate from low rpm up till you reach your desired boost level which will decrease spool time. Without co2 you can only apply as much pressure to the gate as you have in the intake manifold or a pre ic source so even if you have a solenoid bleeding the bottom of the gate you still have exhaust manifold pressure to deal with depending on the size of your turbo.... lots of different ways to skin a cat

 

So are the top cars are using AMS as a standalone or in conjunction w/ their ems?

I figured most were doing ground speed boost off the rear wheel maybe in unison w/ some form of traction control measuring slip % at the front wheel vs the rear.

Right now the car is boost off the rear wheel speed.
Maybe I should've kept my boostleash a little longer as back up, lol.


Instead of plumbing the solenoid to receive manifold pressure, I can just set the regulator to 50-60psi, and plumb it to my solenoid instead, for a little extra response? I have a full 2.5lb bottle bolted to the cage with a line ran to the bay already, so why not if it helps, even if marginally. Doesn't reduce the granularity with the solenoid setup though right?

CO_Racefab, pm coming your way regarding the solenoids.

 

So will dual 3 ports increase or decrease spool time? Or will it stay the same as running a single 3 port? From my understanding it should decrease time due to the push/pull motion from 2 controllers rather than just the pushing down motion from 1 controller. Is the correct?

 

Honestly its beyond me why anyone would use a secondary controller the boost control on all aem boxes is adequate, motec is great hell even s300 works well and all of can be based off ground speed... i doubt the super fast guys are using anything other than their actual ecu to control boost, my car isnt super fast just yet but im 100% positive the infinity boost control will work just fine for low 8s

 

You are correct by bleeding the bottom of the gate you are going to be working the gate much more efficiently. You are essentially taking bottom pressure out of the equation and no longer need to fight the bottom of the gate.

 

As far as I know I'm the only guy using the AMS-2000. It can be done other ways, but I wanted the best. It's much easier to setup initially and its control method is what I wanted from a boost controller.

I plan on racing my car a lot this year, so hopefully times will tell. I had zero time on it in 2015 other than dyno time and parking lot hole shots to setup launch control.

 

parking lot holeshots are great! i used to use my 1/8 mile drive way for 60ft tuning, but now I have a rwd so traction tuning isnt too much of an issue

 

I have had cars go 8's with one 3ports, two 3port, 4port, C02 and no C02. It doesnt matter what method you use as long as YOU can make it work for your needs. IMO boost control isnt that important..

 

It's all In how you manipulate the boost and power output of the engine. There isn't any single thing that'll make you fast. Takes a effort of multiple systems and setup to make it happen.