Turbo Buick Forums banner
1 - 7 of 7 Posts

·
Registered
Joined
·
491 Posts
Discussion Starter · #1 ·
Ok, one side of the solenoid has +12VDC, the other side grounded by ECM---is the ECM lead normally grounded until solenoid is pulsed to limit boost(intermittently opening up the circuit), or does ECM start to pulse this lead to ground potential when limiting boost(intermittently closing the circuit)?
 

·
Premium Member
Joined
·
43,735 Posts
The ecm pulses the ground. When the ground is open, the solenoid cannot bleed off the boost and that provides the minimum boost as determined by the actuator spring/rod length.

As the ecm provides the ground, the solenoid opens thereby allowing it to act as a bleeder. The more it pulses, the more it is open, and the more boost you have. :)
 

·
Registered
Joined
·
491 Posts
Discussion Starter · #3 ·
Ahhhh, therein lies the problem----I was thinking of the solenoid working backwards from that. I will have to break into that circuit then....experiment is coming along Steve! Maybe some results tomorrow evening.
 

·
Premium Member
Joined
·
43,735 Posts
Hope it works well! :)
 

·
Registered
Joined
·
2,098 Posts
Yes, what Steve said. The ECM does NOT limit boost. It adds to whatever the wastegate rod is set for. If you want lower boost, you'll have to lengthen the rod, can't do it with the ECM/Chip. Some chips add more than others, some chips add more in first and second gears than in third/fourth, but none of the can lower it. Confusing?
 

·
Registered
Joined
·
491 Posts
Discussion Starter · #6 ·
Well Steve, looks like the experiment is a success! Can't do any real testing tonight since it decided to rain, but has been tested to the point of proving that I am limited to about 3-5 psi(depending on throttle), and full boost almost immediately after releasing the brake. Can't wait for drier roads for some real world testing and do some recording.
 

·
Premium Member
Joined
·
43,735 Posts
Kewl! I hope it fullfills the promise...pretty neat idea!
 
1 - 7 of 7 Posts
Top