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I have been playing around with boost control on my GTR, using an AVCR and two types of bleed. So far, I have had the best result with the bleed type boost control. (I have since been advised that the AVCR is a bit of a dud on a GTR, due to spiking and generally inconsistent boost control.)

I have been trying to beat the spiking that I assume is caused by the long feedback length of the boost control system. In contrast, on my WRX the boost feed line to the wastegate comes off the compressor outlet, so the pressure signal gets to the wastegate very quickly - no spiking - in fact you need to tune out creep.

Obviously, in the GTR as the pressure feed runs off the intake manifold, the manifold is seeing pressure before the pressure signal makes its way to the wastegates, so some spiking would seem unavoidable regardless of the boost controller type.

Anyhoo... getting to the question... Has anyone tried/considered tapping into the pipe that connects to the compressor outlets for the pressure signal for the wastegates? (say, drilling and tapping a hole and fitting a hose barb?)

This would make the length of the boost control system MUCH shorter and should get rid of the spiking issues. I suspect that the AVCR might even work with this set up.

Thoughts anyone?

Edited by clayoth
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Isnt it meant to be fitted in that way? i dont know anything about AVCRs, but thats how that Jaycar IEBC is installed.

I think most people fit the solenoid where the standard one is normally located and then attached a hose from the intake manifold to the solenoid, and then from the solenoid around to the other side of the engine where the wastegates (turbos) are. This makes the boost control system really long, which will tend to cause spikes.

My thoughts are to block the original vac/boost line from the manifold and add a barb fitting to the turbo compressor collector pipe and use that as the boost feed for the wastegates. I was wondering whether anyone has done it (with success) before I go hacking up my car. :)

Cheers...

No

I get zero spike on my blitz dsbc-r

I have the unit sitting under the airbox, and feeds running directly to the wastegate actuators. There is probably no more than half a metre of hose going to the furthest actuator. Boost line comes off one of the hoses from the carbon canister sitting near the airbox. So really, if you reduce your hose lengths, you should reduce the amount of spiking.

Good luck :(

  • 4 weeks later...

im also running the avcr on my gtr, my problem is boost drop. its set on 1.1 bar max then drops to 1 then then creeps back up to 1.1. i've tried increasing the solenoid duty at the drop points which helps a little bit but cant seem to get it dead straight. im curious as to how the f/b speed setting may help this problem?

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