2nd Generation Specific 1986-1992 Discussion

Manual Boost Controller

Thread Tools
 
Search this Thread
 
Old 10-30-2007, 10:32 PM
  #1  
Senior Member
Thread Starter
 
cps87rx7se's Avatar
 
Join Date: Sep 2003
Location: Albany, New York
Posts: 571
Default

I am new to the whole turbo scene, and I was looking at the diagram for the boost controller and it says to connect one end to a boost source, and the other end to the waste gate. I connected the boost source to the nipple on the compressor housing, and then connected the other line to the wastegate. Does this sound correct to you guys who are using manual boost controllers? Thanks.



CHRIS
cps87rx7se is offline  
Old 10-31-2007, 06:01 AM
  #2  
Super Moderator
 
1988RedT2's Avatar
 
Join Date: Apr 2002
Location: VA
Posts: 2,532
Default

Yes. The wastegate actuator has a spring that will open at (let's say) five pounds of boost. The manual boost controller (MBC) consists of another spring and a ball valve which can be adjusted to keep boost pressure off the wastegate actuator until the boost is sufficient to overcome the MBC spring pressure. The MBC goes in the line from the compressor housing to the wastegate. Be sure it is oriented correctly! It will only work one way. The other way, it won't open and you will see as much boost as your turbo can muster. Be sure to have an accurate boost gauge, and proceed with caution!



And of course you know that you shouldn't be raising the boost level without sufficient fuel and the means to control it, so we'll assume you're good in that department.



Enjoy!
1988RedT2 is offline  
Old 10-31-2007, 10:51 AM
  #3  
Junior Member
 
auricom's Avatar
 
Join Date: Oct 2007
Location: Dearborn Michigan
Posts: 21
Default

not sure the details on this one, but some wastegates are designed to open when they "see" 5 psi for example, when in reality, your vac lines are at 12 psi for example. this is accomplished by an electronically controlled air valve. the electronic air valve and the ECU will work together to tell the wastegate what pressure to open, but its not necessarily the pressure your manifold "sees". did your set up previously go through one of the air valves on the front drivers side of the engine before heading to the wastegate actuator? if so, you might want to put an air line up against your waste gate actuator and observe what psi it begins to open, and at which psi it is fully open. you might not even have to worry about this, but it might be a good idea to check. if your wastegate operates like this, and you ignore it, you could accidentally overboost a LOT.
auricom is offline  
Old 10-31-2007, 03:20 PM
  #4  
Senior Member
Thread Starter
 
cps87rx7se's Avatar
 
Join Date: Sep 2003
Location: Albany, New York
Posts: 571
Default

Originally Posted by 1988RedT2' post='886779' date='Oct 31 2007, 03:01 AM
Yes. The wastegate actuator has a spring that will open at (let's say) five pounds of boost. The manual boost controller (MBC) consists of another spring and a ball valve which can be adjusted to keep boost pressure off the wastegate actuator until the boost is sufficient to overcome the MBC spring pressure. The MBC goes in the line from the compressor housing to the wastegate. Be sure it is oriented correctly! It will only work one way. The other way, it won't open and you will see as much boost as your turbo can muster. Be sure to have an accurate boost gauge, and proceed with caution!



And of course you know that you shouldn't be raising the boost level without sufficient fuel and the means to control it, so we'll assume you're good in that department.



Enjoy!


I have a Walbro 255LPH fuel pump and an APex'i SAFC to control it. I am going to have it tuned for 8psi. This actually leads me into another question; what can the stock turbo handle for psi? Not that I am going to hit it, but want to stay below it. Thanks.



CHRIS
cps87rx7se is offline  
Old 10-31-2007, 06:45 PM
  #5  
Super Moderator
 
1988RedT2's Avatar
 
Join Date: Apr 2002
Location: VA
Posts: 2,532
Default

Originally Posted by cps87rx7se' post='886812' date='Oct 31 2007, 04:20 PM
I have a Walbro 255LPH fuel pump and an APex'i SAFC to control it. I am going to have it tuned for 8psi. This actually leads me into another question; what can the stock turbo handle for psi? Not that I am going to hit it, but want to stay below it. Thanks.



CHRIS




I have heard that the stock turbos do not run for long on anything much over 12 psi before the center sections start puking oil. Mine was rebuilt and had a larger compressor fitted. I'm currently running around 18 psi without issues, but this car is rarely driven and longevity is not so much an issue for me. Even before the rebuild, I had no trouble hitting 12 psi on the stock turbo.
1988RedT2 is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
slissek
Performance Mods
0
05-23-2012 07:18 PM
Kouta
Northwest Regional For Sale Forum
3
02-13-2006 06:30 PM
FikseRxSeven
3rd Generation Specific
14
10-19-2003 12:40 AM
turbovr6
RX-7 & RX-8 Parts For Sale & Wanted
6
04-30-2003 12:08 AM
vosko
RX-7 & RX-8 Parts For Sale & Wanted
0
10-29-2002 11:25 AM

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 


Quick Reply: Manual Boost Controller



All times are GMT -5. The time now is 12:35 PM.