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Post up the boost control table. 

I couldn't watch the video but it sounds like you're asking the boost controller to cycle around the idle areas of the map. Simply pull the duty cycle out of those areas of the map, it's not like your making boost at idle anyway lol.

Edited by Murray_Calavera
  • Like 2
4 hours ago, Murray_Calavera said:

Post up the boost control table. 

I couldn't watch the video but it sounds like you're asking the boost controller to cycle around the idle areas of the map. Simply pull the duty cycle out of those areas of the map, it's not like your making boost at idle anyway lol.

I haven't messed with the boost table at all. I loaded the base tune and adjusted MAFs / TPS output for the ATESSA / fuel sender

 

Here's what the boost table is set to.

 

 

 

20201016_031425.jpg

20201016_031456.jpg

38 minutes ago, RTSKY33 said:

I changed the options on the link so everyone should be able to view it now.

So that's going to be commanding 22 %, change the first number to 0 and all good, then adjust the axis values to more sensible values

45 minutes ago, Ben C34 said:

So that's going to be commanding 22 %, change the first number to 0 and all good, then adjust the axis values to more sensible values

I set the first value to 0 and it fixed the issue. Im new the ECU things so I'm not sure of what the other value should be set to.

Thanks for helping me out!

The stock solenoid works differently. It is pulsed from standard, but thats not practically the problem. The problem is that when de-energised it is normally closed, as opposed to normally open as you would with a 3 port Mac valve setup with wastegate actuator. The vacuum arrangement is different when using a normally open valve too.

The stock solenoid feed from plenum is tee'd and directly the feeds solenoid and wastegate actuators, then ecu commands solenoid to energise and open, bleeding off the excess boost pressure actuator boost signal to back Infront of the turbos. A normally open Mac valve would not be tee'd and be fed directly from plenum, then to actuators. This normally closed setup is more like an external gate setup, except the bleed port is going back in front of turbos as an actuator air bleed instead of going to the second preloading port on an external gate.

Why Nissan why ?

Stock setup is stupid and appears to have problems controlling higher than stock boost pressures, that is, not being able to bleed off enough air to raise / control boost properly, reliably or consistently.

2 hours ago, BK said:

Why Nissan why ?

Because it's just a 2 state bleed. It's a digital on-off arrangement. With Nissan it's X (where X is a fixed 5 or 10 or similar) psi from the spring with the solenoid closed and Z (=X + Y where Y is a fixed 2 or 3 or 5 or something similar) psi when open and bleeding.

Mac valves are throttled by the PWM controller to give an analogue effect. With PWM control, it's X + A where A can be anything at any time depending on the limits of the bleed size, duty cycle limits, etc.

  • Like 1

So replace the stock one with an automotive MAC Valve. As its Provisioned for PWM it will work intended with the Haltech ECU, correct?

also, will using the same plumbing/wiring be an issue?

Edited by SLVRBAKSLPZ
1 hour ago, Dose Pipe Sutututu said:

Wiring fine, you'll need to slightly replumb

Is this accurate on how to modify the plumbing? Port 1 vent to Atmosphere // Wastegate to port 2 // Direct from plenum to port 3

MAC_Plumbing_Diagram.jpg

Looks about right, diagram is giving me a headache lol.

Essentially you want the boost source from your plenum (only applies to RB26 as throttles are post plenum).

5 minutes ago, Dose Pipe Sutututu said:

Looks about right, diagram is giving me a headache lol.

Essentially you want the boost source from your plenum (only applies to RB26 as throttles are post plenum) and block off the OEM bleed.

Im sorry. seems all the pictures on Google are already scribbled on.

 

But basically the long green line needs to get routed to the plenum where the short ones goes into, correct? It looks like I can reach that line and re-route w/o pulling the plenum.

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