Convert dual wastegate solenoids to single?

  • Login, members don't see Ads!

jyamona

Captain
Free Vendor
Nov 7, 2016
1,020
Philly
Is it possible to convert to using just one wastegate solenoid to control both turbos? Can JB4 or MHD account for this?”
It is possible and works fine. You will get a code for the missing one though now. Your tuner can turn it off using the same toggles people use for single turbo / boostbox.
 
  • 1Like
Reactions: screaminfast

screaminfast

Corporal
Feb 18, 2017
183
Rochester NY
It is possible and works fine. You will get a code for the missing one though now. Your tuner can turn it off using the same toggles people use for single turbo / boostbox.
Good to know. Thanks Jake! I should probably get a brand new one since I have no idea how old mine are.
 

Panzerfaust

Lieutenant
Jul 3, 2018
541
Chicago
Like Jake said, definitely doable. But like our vacuum canisters, they're there for a reason and you typically will experience some loss in spool time/WGDC by removing one (or both in the case of the canisters)
 
  • 1Dislike
Reactions: Mikejones1208

Panzerfaust

Lieutenant
Jul 3, 2018
541
Chicago
So... I still have some learning to do on this, but the 740i has no canisters at all. Right @BQTuning? Just larger solenoids/lines?
740 has canisters built into the engine cover iirc.
Our N54 has been Single Boost solenoid and no vac canisters for probably 2 years now maybe more. You'll be fine.
Oh certainly it will run fine. I feel like people are misinterpreting my original post here (not you, Justin).

My point was the vacuum canisters are there to hold vacuum and at higher levels for quicker response from the vacuum-actuated components due to our relatively small vacuum pump system - which I've heard is especially useful at higher elevations - but can definitely be deleted, just at a potential slight cost in response time. Same for the boost solenoids, there's one for each turbo so that they have "dedicated" solenoids controlling them for quicker and individual WGDC control rather than tee'ing from one solenoid for both. I imagine the impact of running one solenoid is probably only about the same as Tee'ing for DVs though - it's certainly effective still, but a dedicated vac line for each would generally yield a better response, no?
 

Twisted Tuning

Lieutenant
Platinum Vendor
Oct 25, 2016
869
New York
740 has canisters built into the engine cover iirc.

Oh certainly it will run fine. I feel like people are misinterpreting my original post here (not you, Justin).

My point was the vacuum canisters are there to hold vacuum and at higher levels for quicker response from the vacuum-actuated components due to our relatively small vacuum pump system - which I've heard is especially useful at higher elevations - but can definitely be deleted, just at a potential slight cost in response time. Same for the boost solenoids, there's one for each turbo so that they have "dedicated" solenoids controlling them for quicker and individual WGDC control rather than tee'ing from one solenoid for both. I imagine the impact of running one solenoid is probably only about the same as Tee'ing for DVs though - it's certainly effective still, but a dedicated vac line for each would generally yield a better response, no?

just based on my experience. response actually felt significantly better on one solenoid witho no vac canisters. I didnt do any scientific testing, but it was easily felt on my car. But yea, the theory behind the canisters is for high elevation use. Im at sea level for the most part, but travel up to like 1300 feet almost daily. which isnt holding a candle to COlorado users. and those at other higher elevations. SO i have no experience beyond 1300ft with this particular mod.
 

screaminfast

Corporal
Feb 18, 2017
183
Rochester NY
just based on my experience. response actually felt significantly better on one solenoid witho no vac canisters. I didnt do any scientific testing, but it was easily felt on my car. But yea, the theory behind the canisters is for high elevation use. Im at sea level for the most part, but travel up to like 1300 feet almost daily. which isnt holding a candle to COlorado users. and those at other higher elevations. SO i have no experience beyond 1300ft with this particular mod.
Thanks Justin for the insight. I’m all about cleaning up the engine bay lately. Gotta get you to come out to WNY some time.
 

Mikejones1208

Corporal
Dec 6, 2016
109
Savannah, GA
740 has canisters built into the engine cover iirc.

Oh certainly it will run fine. I feel like people are misinterpreting my original post here (not you, Justin).

My point was the vacuum canisters are there to hold vacuum and at higher levels for quicker response from the vacuum-actuated components due to our relatively small vacuum pump system - which I've heard is especially useful at higher elevations - but can definitely be deleted, just at a potential slight cost in response time. Same for the boost solenoids, there's one for each turbo so that they have "dedicated" solenoids controlling them for quicker and individual WGDC control rather than tee'ing from one solenoid for both. I imagine the impact of running one solenoid is probably only about the same as Tee'ing for DVs though - it's certainly effective still, but a dedicated vac line for each would generally yield a better response, no?
The solenoids are not ran separate from one another and dedicated to each turbo, they tee together and act as one solenoid actuating together at all times, eliminating one will not make a difference at all in spool time or responsiveness, ive deleted one from cars to troubleshoot them and spool time and responsiveness was identical to running 2 if the one you leave hooked up is in good working order. Same goes for deleting vac cannisters, only time those really help is if your in a high altitude setting and even then from some people ive talked to they dont notice a difference either. But i live at sea level and all the cars locally to me that ive worked on and deleted for have never reported back with any problems or changes in car behavior at all
 

Panzerfaust

Lieutenant
Jul 3, 2018
541
Chicago
The solenoids are not ran separate from one another and dedicated to each turbo, they tee together and act as one solenoid actuating together at all times, eliminating one will not make a difference at all in spool time or responsiveness, ive deleted one from cars to troubleshoot them and spool time and responsiveness was identical to running 2 if the one you leave hooked up is in good working order. Same goes for deleting vac cannisters, only time those really help is if your in a high altitude setting and even then from some people ive talked to they dont notice a difference either. But i live at sea level and all the cars locally to me that ive worked on and deleted for have never reported back with any problems or changes in car behavior at all
That's why I put 'dedicated' in quotes about the vac solenoids - I'm well aware they connect together, but theres still one for each turbo. As for the vac canister delete, as I've said before in this thread, it's been done with success plenty of times but *may* effect some vac actuated components. I've heard from some tuners that they saw a ~3% change in WGDC down low under WOT when deleting the canisters. That's something most certainly might not feel, especially with our smaller twin turbos and the small difference it makes - but it's still there and could effect other users more.

I'm not saying all 4 things are necessary, as I've pointed out several other times in this thread. I'm simply stating the technical reasons we have them. We have a relatively small vacuum pump so BMW felt that adding the canisters and running two solenoids would help with quicker vacuum response.
 

GreyNBlueE92

Specialist
Oct 3, 2018
98
OH
I want to hook a failsafe up to the grounds of the boost solenoids. Will wiring them together using the same ground work or will that cause some sort of interference? Its an AEM failsafe gauge. I would like to see if I can get both working with the failsafe before I delete one (if I have to).

Any input is appreciated. Thanks!
 

aus335iguy

Lieutenant
Nov 18, 2017
950
Is there anything special about these solenoids or can they be replaced with generic off the shelf parts. I don't have a 30FE code I swear... Asking for a friend :)
 

NoQuarter

Captain
Nov 24, 2017
1,063
Indiana
Is there anything special about these solenoids or can they be replaced with generic off the shelf parts. I don't have a 30FE code I swear... Asking for a friend :)
You are going to want to stick with the OEM solenoids so they have the expected response time for the given control voltage/current/PWM from the DME
 
Top