Vacuum solenoid for manual boost controller?

[sc2_ct]

I know I've seen something about this somewhere but I couldn't find anything in my search. I've got a manual boost controller that I made for my previous DSM, but I would like to convert it to selectable controller by adding a vacuum solenoid (flip a switch for higher boost, but otherwise run at stock boost). I was wondering if anyone knew where a good source would be to find the appropriate vacuum solenoids for this use?

 

[AWD90DSM]

i did this on my old 1g.. i used the stock boost solenoid. i believe its a "normally open" solenoid... so if there is no voltage to it, its open, allowing the boost to go directly to the wastegate... if you apply voltage, it closes, forcing the boost pressure to go through the MBC, allowing you to go from stock boost to MBC setting with the flip of a switch.

works the same way as the turboXS or Dejon hi/lo, which i have on my 2g now. you might as well give it a try

 

[CyberEye]

Sounds liek it would work in theory, but how would you tune for it? Unless you have an AEM EMS or something. If you're using a SAFC, how are you going to tune it for two different boost settings?

 

[sc2_ct]

Pretty much I need a vacuum switching valve that can be switched via an in-car switch, and depending on whether the valve is open or closed will determine whether I am running off of the MBC or if it is directed to the stock boost control solenoid. In other words I just need something to re-direct between the original boost control solenoid and the manual boost controller. I could use a manual valve but that would mean either getting out of the car to select back and forth, or running a ton of vacuum line which wouldn't work out any better for in-car use.

 

[AWD90DSM]

let me explain my previous post a little better. because i did in fact do this, and it did in fact work well.

if you splice the stock solenoid between the MBC and the WG actuator (one end of the solenoid in the boos source before the MBC, and the other end after the MBC closer to the WG actuator) you can run 12v to the solenoid with a switch in between in the cockpit to control power to the solenoid.

i made a crappy drawing in paint to better show what im talking about.

if the solenoid has power, and is therefore closed, the boost will have to go through the MBC.... without power, the solenoid will allow the boost to go directly to the WG

 

[sc2_ct]

aha, I see, that makes perfect sense - it's a much more elegant solution than what I was thinking of

 

[CyberEye]

Again, how are you going to tune for it? Without someway to tune for the two different boost settings, you'd might as well just set it to the higher setting.

 

[sc2_ct]

Again, how are you going to tune for it? Without someway to tune for the two different boost settings, you'd might as well just set it to the higher setting.

I'm only going to be running 14 psi or so with cat back, intake and IC tubing so I won't have any problems. If I run lean at the high setting I'll just dial it back a little. This car is just a daily driver and isn't going to be modified to the point of needing anything but the most basic of tuning -- the RRFPR should suffice for my needs. The car is an auto with the 13G after all...

 

[AWD90DSM]

doesnt the afcII allow you to have 2 fuel maps anyway?

 

[CyberEye]

doesnt the afcII allow you to have 2 fuel maps anyway?

yeah it does, I Just realized that last night while reading the instruction book for my new one.

 

[CyberEye]

I'm only going to be running 14 psi or so with cat back, intake and IC tubing so I won't have any problems. If I run lean at the high setting I'll just dial it back a little. This car is just a daily driver and isn't going to be modified to the point of needing anything but the most basic of tuning -- the RRFPR should suffice for my needs. The car is an auto with the 13G after all...

If you're only going to be running 14psi at the high end, why not just run 14 all the time?

 

[sc2_ct]

If you're only going to be running 14psi at the high end, why not just run 14 all the time?

Heat, wear & tear, fuel consumption, long term reliability and during daily driving I don't really need it all the time. I drive somewhat spiritedly occasionally in a very hilly area where the car really does see full boost even going up some of the hills driving somewhat normally. If I had the power all the time, I'd use it all the time

My last TSi had a T3 60-trim, 600cc injectors, 3" turbo-back, hardpipes, AFC, etc and got all of 15-17 MPG -- which I really don't feel like doing again in a daily driver. Anymore I'm just aiming for an extremely mild increase on the order of 30 hp or so.

Eventually I'll be picking up another 1g for a project car and then maybe I'll go crazy again, seeing as I still have my T3 super 60, injectors, mbc, external wastegate and the like in boxes in the basement. The current one is just supposed to be a fun, peppy car to get back and forth in.

 

[Turbo Talon DL]

I love the idea BTW, just LLOOVVE it! I actually thought up something like this, only the MBC wasnt part of the solution. I thought of splicing into the wire from the
ecu-->BCS and using a potentiometer, (variable resistor) and could kinda make an EBC from the stock stuff. I havent tried it or anything yet, but in theory sounds like it should work. Good idea tho..

And as for tuning for two settings, why? Just tune for the high setting and it will be fine. If you run less boost for what your max tune is, its not going to hurt anything.

 

[CyberEye]

I'm probably bringing this back from the dead. But I was wondering/trying to think of how I'd be able to do this since I'm not using the BCS? I've bypassed the BCS as per the 16g install vfaq. Any suggestions?

 

[Turbo Talon DL]

Im resurrecting the dinosaurs again ! but i just did this mod today. DO NOT USE the stock BCS!! Use the stock fuel pressure solenoid. Its actually what you need. Its open/off and closed/on. The stock BCS is the exact opposite.

 

[Defiant]

http://www.dsm.org/archives/1997/11/19971128.txt/10.html