Strange Boost Issues

[Bobzor]

Hello all,

 

I guess an introduction is in order first!

 

I purchased a JDM 2001 Legacy Blitzen back in May after a friend of mine convinced me to stay away from a few Skylines I was looking at, and boy am I glad he did. I have been in love with this thing since I bought it. My girlfriend loves it so much she traded in her Mazda 3 for a Subaru Forester herself, but thats another story, lol.

 

As far as I can tell, the car is totally stock, except for a digital boost guage. Anywho, here is the issue I'm having in as simple a way of putting it as I can.

 

1. Primary boosts to .5 bar, hesitates for a split second then continues to climb to .8 to 1 bar.

 

2. VOD kicks in as usual, but boost drops to .3 to .4 bar (a large drop from .8)

 

3. Secondary will climb very slowly to 1.2 bar if WOT, much better if slightly off the pedal

 

If I'm not WOT, the boost will often build much better on the secondary. Sometimes, when I shift, boost climbs to .2 to .4 bar, holds for a half second, drops to 0 for 4 or 5 seconds, than climbs. This can be replicated 100% if I'm shifting anywhere near the VOD.

 

So far I have replumbed the solenoid box, and cleaned out all solenoids twice, save for the one on the passenger side wing. (What a bitch to get at!) This did seem to help boost on the primary and speed up the secondary a little bit, but the problem remains.

 

From what I've read, the boost should be physically limited on the primary by the actuator, correct? Should I be starting there?

 

I have had experience with single turbo setups in the past, and I'm doing what I can to learn this much more complicated dual setup lol.

 

Does anyone have any advice that may help me narrow down my issue?

[fahr_side]

The 'valley of death' is unavoidable. Switch to a single turbo if you want to be rid of this 'feature'.

[Bobzor]

The 'valley of death' is unavoidable. Switch to a single turbo if you want to be rid of this 'feature'.

 

Oh, I know that. The VOD is fine, I kind of like the extra kick

 

The problem is with the over boosting primary and issues with the secondary turbo, whether that is from the primary or not.

[Andy_Mac]

The 'valley of death' is unavoidable. Switch to a single turbo if you want to be rid of this 'feature'.

 

 

Definately unavoidable, but a tune can make a huge difference to how bad it is. Thats a local guy who tuned it himself so surely a good tuner can improve on that further. The boost drop at the VOD has been set up the way it is to still retain the secondary pre-spooling 'feature' without dropping power/torque too dramatically.

 

 

http://img.photobucket.com/albums/v625/Markyface/Before%20amp%20after_zpsvozjfnjr.jpg