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Discussion Starter · #1 ·
had my car up for mapping yesterday. all went well, until 6000rpm. i am running d-jetro and an apexi avcr. when the tor/bhp graphs get to 6k there is a drop then spike then drop then spike to 8k?,. we tried all ways of mapping it out using the avcr also wired the boost solenoid to the original solonoid wires and activated boost kit in the ecu? this seem to cure the problem on the rollers, but the solonoid clicks all the time, then on the way home first time to open it up about 7 miles from the dyno it spiked at 1.76bar.:mad: saw a thread on datalogit ref ( sawtooth ) on the gtrs on a dyno dynamics roller. any help would be appreciated guys.. at the moment i have wired the avcr in but this will spike up and down at 6-8k... help please..bernie. p.s final figures were 560bhp/460ilbs @ 6k.

basic spec, 2530/720/264/272 9.15mm/forgies/n1 oil/water/hks elbows/tomei fuel/hks fuel reg/exedy twin..
 

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D-jetro means a PFC taking care of the boost right? So what's the need for an AVC-R???
 

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AVC-R for boost control maybe, but I'd let the PFC do it all..
 

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Was the boost oscillating? What was AFR / Timing / knock level?

You cant wire the AVC-R solenoid into the std wiring harness and run it on the PFC. You need to connect it via the Apexi harness, you`ll get better boost control with the AVC-R anyway.

Try reducing the feedback setting in the `etc` menu on the AVC-R when connected correctly.
 

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Discussion Starter · #5 ·
hi guys the avcr was wired when the car was running afm,s at 400bhp. so just logic to run it..does anyone know the correct way to wire the avcr to the d-jetro ecu. we used the two pin plug that used to go to the std boost solonoid, we wired this to the apexi boost solonoid and left the pressure sensor the same.. but it clicked all the time which is not a problem i suppose.. also when it spiked i went into the hand controller and tried to reduce duty to bring boost down but to no avail?. anyone want to have a guess?.:rolleyes:
 

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R32 Combat said:
AVC-R for boost control maybe, but I'd let the PFC do it all..
That's what I wanted to point out: he has a D-Jetro PFC so let the damn thing take care of the boost & get rid of the AVC-R... ;)
 

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The DJetro should do it all.

It will require the Apexi map sensors ( two for the DJetro) and the boost solenoid connected.

You will need a wideband Lambda and some detonation monitoring equipment before you run it on boost without risking meltdown.

Get rid of the avcr.

From memory the solenoid should start clicking at .6 bar of boost.

You've gotta big bill coming if you start driving it hard without the basics sorted.
 

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The AVC-R has some features which may make it preferrable to keep.

You can't really setup boost control on a rolling road and expect it to work properly on the road.
 

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As stated above, the AVC-R will giver better boost control as the software has more features.

D-jetro has nothing to do with boost control.

The downside of using AVC-R is the loss of closed loop boost control with regard to some safety features.

As Hugh says, it sounds very much like your not really experienced in any of this, as was the rolling road you used. Wild boost/power oscillations at 6K+ are not something to take lightly!
 

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Hugh - The chap above seemed to be suggesting the difference with the `D type PFC` is boost control - clearly both MAF / MAP system can control boost.

What the AVC-R has over PFC: (that I can remember now!)

Gear Based boost control
RPM Based boost settings
Gear based feedback settings (to control boost oscillations / undershoot)
 

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Discussion Starter · #12 ·
cheers guys, hugh just to clarify i have 2 map sensors for the d-jetro, you say i need one more the same then wire this to the apexi boost solonoid and let the ecu control boost..thanks guys..

p.s do i still keep the avcr pressure sensor on the firewall?.

if not could be an avcr going cheap..:D
 

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rockabilly,

As I posted the DJetro has two map sensors and will, with the correct wiring and boost solenoid connected to the ecu, control your boost.

I have not used an AVCR, so cannot comment about the additional advantages it will bring.

For myself there is only one boost setting required and that is the maximum Rod will allow me to use to stay safe on the engine - perfect for all situations.
 

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"For myself there is only one boost setting required and that is the maximum Rod will allow me to use to stay safe on the engine - perfect for all situations."

:clap: :chuckle: :chuckle:

Brilliant answer / quote. :bowdown1:

cokey
 

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Hugh Keir said:
For myself there is only one boost setting required and that is the maximum Rod will allow me to use to stay safe on the engine - perfect for all situations.
Yep, exactly. Who needs low boost. Actually, about EVERY AVC-R I have ever seen does not take advantage of any of the additional features it can use.

Most people use it as a straight boost control, at which point, the Boost control kit built into the Power FC works fine. +/- 0.1.

Back to the original issue, if you run base boost (lowest boost) what happens on the dyno ?

Could be the feedback on the WG. Could be hitting some kind of cut in the AVCR. Could be hitting a cut in the Power FC. Could be an ignition issue. Could be a CAS.
 

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Discussion Starter · #16 ·
cheers sean.car runs mint but i had it mapped on a dyno dynamics 4wd roller set up and have seen a thread on the datalogit site mentioning something about sawtooth?.will dig deeper still cheers guys..
 

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The sawtooth, the Datalogit guys say it was the dyno, and the torque split between the front and rear wheels.

Also, boost controllers should be called " boost - close enough, or boost guessers". You have boost source, controlling a mechanical actuator, the boost source controlled by some electro mechanical solenoid.

Its honestly easier to get it wrong than right. Most of the time, most setups as long as its within a few psi I am happy.
 

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Discussion Starter · #18 ·
thanks sean. will take it out sunday and have a careful play with the avcr settings, then if no joy will fit a third map and wire it to the d-jetro ecu and let that run the boost..bernie.
 
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