Quote:
Originally Posted by Tuned335i
I assume everyone with a boost gauge has it installed in the same place, i.e., in the diverter valve (the BMW documentation calls them blow off valves). Is there any way that the spikes in boost could be just what is seen inside the intake piping between the intercooler and the throttle plate because the spring loaded diverter valves are not reacting fast enough, possibly due to the fact that we're running +6-7psi more than a stock engine?
Eugen mentioned this a few posts ago and after reading the documentation section on Blow-off Control, and it sounds like that could be a contributing factor...
If this is true, then the engine itself isn't seeing the boost spike, but it's spiking in the intake plumbing and at the intake turbine itself which apparently is exactly what the diverter/blow-off valves are supposed to prevent.
Someone who knows about this stuff needs to chime in... |
Good question…I would like to know how it all being instrumented as well.
The diaphragm valve by its design is fast reacting. The problem with this valve is they are not typically designed for differential pressure more than 10-12 PSI. At higher pressure the valve can start to work unexpectedly due to fluttering or seating and resetting problems and could cause a momentary restriction or even leak after resetting. The behavior can be very inconstant and hard to repeat. It is not very clear if the valve is designed to work at this pressure or if Shiv has even validated this. I don’t think the plumping would cause enough of restriction to be of any concern.
It doesn’t look like this is a problem but I wouldn’t rule it out. Too many pieces are missing to get a clear picture.
I think Shiv will need to chime in to clarify all our assumptions.
Orb