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I've been looking at what nismosilvia270r about combining the charge control (CC) and charge relief (CR) solenoids into one 4-way. The only issue I see is that the CR is energized up to 4000rpm, then from 4000rpm-5500rpm both the CC and CR are de-energized, then at 5500rpm the CC is energized according to documentation below.
So there is not a immediate switch over. Would it matter if they switched at the same time somewhere in the 4000rpm-5500rpm range?
If so, with the CC and CR combined I roughly diagrammed the plumbing:
Using the modular Fabcos, if you replaced all of the remaining solenoids you would have:
1 x 104MG-2-V-12VDC - CC/CR
1 x 103MG-2-V-12VDC - Turbo Control Vacuum (TCV)
1 x 103SMG-2-V-12VDC - Turbo Control Pressure (TCP)
3 x 102SMG-2-V-12VDC - Turbo Precontrol (TCP), Wastegate Control (WGC), Purge Control (PC)
The TCV and CR/CC would be manifolded together like linnadawg did above, but you only need a 3-way for the TCV, not a 4-way. Although from his post, seems like he just ordered four 4-ways to play around with configurations. The rest of the solenoids would be stacked next to each other similar to how AzeKnight, RedRevolver, or saxyman990 did it.
As Julian pointed out earlier in the thread, whatever solenoid you put on the end could be designated as a pressure manifold (MG instead of SMG for the individual inlets) so you could put an elbow on the side, plug the port on the front and it would be a little cleaner. Could just make them all manifolded and internally plug them as linnadawg did, idk if that would have any advantages. Lots of different configurations.
One thing I'm not sure about is which orifice size to use. On most people's setups, they used #2 giving giving a Cv of .075, however linnadawg used #3 giving a Cv factor of .156. Julian said here that the .156 is close to the flow rate of the wastegate controller, but I haven't found anywhere giving the flow rates for the others.
Let me know what y'all think.
Last edited by kelldog44; 08-04-20 at 02:03 PM.
Reason: image didn't uplaod properly
Charge relief opens at a lower RPM to allow boost pressure from the spooling but not yet online secondary turbo somewhere to go. If you closed it and opened the charge control valve at the same time you'd probably have a substantial drop in boost - the secondary turbo would not be pre-spooling properly and would be semi-stalled when it was brought online.
What's the difference between the -MG and -SMG valves? Fabco specs say that "M" is "individual inlet" and "SM" is "manifolded inlet (pressure manifold)" but I'm not sure what that means.
I'm also curious whether anyone has tried running the Fabco 2-way valves as suggested by @kelldog44 for TPC and WGC.
A prior owner of my FD did a quick & dirty non-sequential job (oh, that's why I have no primary boost...) and I have a feeling I'm about to find some dead solenoids.
What's the difference between the -MG and -SMG valves? Fabco specs say that "M" is "individual inlet" and "SM" is "manifolded inlet (pressure manifold)" but I'm not sure what that means.
I'm also curious whether anyone has tried running the Fabco 2-way valves as suggested by @kelldog44 for TPC and WGC.
A prior owner of my FD did a quick & dirty non-sequential job (oh, that's why I have no primary boost...) and I have a feeling I'm about to find some dead solenoids.
My (non-expert) understanding is that the "103MG" valves were manifolded and the "103SMG" valves are individual inlet. If the sides of the three-way valve are A, B, and C, the "-MG" valves are designed to share one side of the 3-way valve (the vacuum/pressure "manifold"). So two valves are (for example) sharing an "A" but having separate "B" and "C."
Having 2 "-MG" valves here tidies things up a bit because the one of the turbo control valves and the charge control valve both connect to the vacuum chamber on one side. (For the 103MG part number specifically, each valve also has two internally connected two outlets running perpendicular to the stack, so two identical "B" sides which are shared within a valve but not between valves. However the reason to pick the "103" part number seems to me to be because the 10-24 outlet thread and not because both of the twin outlets are being used.)
Some of the part numbers from earlier in this thread were discontinued. I could only find manifolded versions (with a "113MG-" part number because the block outlets are 1/8 NPT instead of 10-32 threaded). I attached the old/new tech drawings from the catalogs I was able to find. Again I'm not an expert, just have been trying to piece together for myself how to DIY one of these racks.
08-04-20, 02:00 PM
