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Bnr 16g idc 100%


goob_os101

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I have a BNR 16G with Cobb catted DP and stock injectors/fuel pump

 

I am working with a reputable tuner and they noticed the following during request 2nd gear pulls:

 

"Seeing about 16psi near redline which is why the stock injectors are maxing out. I have seen this plenty of times when the wg is around 15psi on the actuator. You can adjust it down a touch if its adjustable and that may give us just enough head room but right now its almost running out of fuel up top due to this."

 

I tried adjusting the actuator but I am still seeing 100% IDC near redline.

 

any suggestions?

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Pump aside, you're still running out of injector. The wastegate sets the mechanical boost your turbo will spool to before it needs additional input from the boost control solenoid to maintain a higher boost level. Adjusting the wastegate lower (it's 13.5 psi on the BNR 16G from the factory) will only give the car more range in which to control boost with the solenoid.

 

Short of it is, you need to run a lower boost target to not max out your injectors. You'll turn down the wastegate to let your tuner actually have some ability to control how the boost comes up, but it won't get you anything in terms of max boost. 16 psi will push the same amount of air into the engine at a given temperature, regardless of where your wastegate is set.

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They are also saying: " I was able to see that your turbo is boost creeping and overshooting our target though. This can normally be remedied by porting the wastegate or going external. You are over 100% injector duty cycle in the logs at 0% wastegate."

 

So is this something that I can't fix mechanically on my, but something they should be able to remedy?

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Ah. They're saying the that the car is pulling all wastegate duty cycle to try to pull the boost back on target, and it's still overboosting/creeping. There's nothing they can do for this from a tuning standpoint - it sounds now like they're saying they want to pull the boost back so your injectors aren't maxed but can't because the mechanically set boost is too high. You still can't run 16 psi (if you're out of injector there), but definitely need to do something on the mechanical side to give them the ability to set a lower target.

 

I run the same turbo/downpipe combo, and can attest to the fact that at 0% wastegate it should hit 13-14 psi max. Here's what I'd consider/check:

 

Are you still running the factory boost control solenoid? If so, did you transfer the line with the boost restrictor pill to the 16G when you installed it?

 

Check all the boost control vacuum lines for leaks or pinches. I've had a split line from the turbo to the boost control solenoid cause huge overboost.

 

Are you sure you adjusted the wastegate actuator in the right direction?

Edited by awfulwaffle
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I do agree with the above posters - you're limiting yourself running that turbo on stock injectors. The original VF40 from your car will push 16 psi without maxing the injectors, which implies that the 16G is running more efficiently and giving your cooler air temps than the stock turbo, which is good. But you're still limiting the potential of the turbo with fueling. Are you purposely keeping the boost low because it's an older motor or something? I'd understand it from that perspective, I suppose.
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Are you still running the factory boost control solenoid? If so, did you transfer the line with the boost restrictor pill to the 16G when you installed it? Not sure if the factory boost control solenoid or if the line with the boost restrictor was swapped over. I bought a 2005 LGT for the motor to put in my OBXT and it was rebuilt and had the BNR 16g already installed.
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Hey there guys, We are tuning it and have seen this happen in the past.

 

Basically we have a double edged sword here. A lot of times the BNR16G and VF52 work great on stock fueling as its VERY expensive to upgrade the fuel system properly to top feed on the 05/06 LGT's and foresters so bang for the buck this is a great upgrade but causes us to not be able to use the full potential of the turbo.

 

Normal gains are still 30-50whp over a vf40 or vf46 but with minimal cost.

 

The issue is sometimes the 16G is set a little to tight or just wants to flow more at wastegate pressure *not a big issue if you have upgraded fueling* and sometimes the vf52 actually creeps WAY past about 15psi. It all has to do with exhaust and intake modifications as well.

 

Most times we give customers 3 options -

 

Adjust the wastegate a touch to see if we can bring it down to a safer level without compromising wastegate control *13psi at redline at about 90% IDC before latency calculated in is still very safe*

 

Port the wastegate *the most common fix as thats the real issue on VF52's as the wg is too small thus not able to bypass enough exhaust gas to hold proper control* / install an external wastegate - and yes, some suffer from it and some dont. Google VF52 boost creep and you will see that a lot of 3rd gen wrx's had this problem at stage 2 levels since it was thier oem turbo supplied.

 

3. Upgrade fueling system for larger injectors which removes the issue 100% on the bnr16g since 15psi is still more than safe once fueling is upgraded BUT is NOT always a fix for a creeping VF52 as they can creep all the way up to 20+ PSI at 0 wg which ends up being unsafe to have no control over boost so a hard downshift with a small wg port can result into the mid 20's on pump gas!

 

Hope this helps some people when deciding the upgrade paths as we have tuned thousands of these setups.

 

Goobs_101 - you have an email describing what I have said here as well but I wanted to share it with the forum as well since its helpful to others I would feel.

 

Have a great day!

 

Dave

[sIGPIC][/sIGPIC]

Providing unmatched customer service and a Premium level of Dyno/E-tuning to the Community

 

cryotuneperformance@yahoo.com

facebook.com/cryotuneperformance.

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I know this is a late response to your question since we already talked but for anyone else needing the info, I dont suggest aftermarket sidefeeds due to the failure rate we have seen over time. Top feed is expensive but the right way to go when upgrading on an 05/06

 

Dave

[sIGPIC][/sIGPIC]

Providing unmatched customer service and a Premium level of Dyno/E-tuning to the Community

 

cryotuneperformance@yahoo.com

facebook.com/cryotuneperformance.

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Dave this is an upgrade I plan to do as well. i already have a set of Blitz side feeds from another build platform, do you recommend not using those? These have about 10k on them. Is it best to go with the top feeds instead and other than injectors what else in the fueling should be upgraded? Sorry for the noob question but this is a new platform for me. TIA~

 

 

 

I know this is a late response to your question since we already talked but for anyone else needing the info, I dont suggest aftermarket sidefeeds due to the failure rate we have seen over time. Top feed is expensive but the right way to go when upgrading on an 05/06

 

Dave

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Hey there,

 

I have had tons of issues over the years with modified sidefeeds and about 4 years ago stopped selling them/installing them and prefer not to tune them due to them being fine...till they are not. I had a few sets fail on personal cars on 91 or e85 so its hit or miss. Some customers have good luck but I would say on average 70% end up with issues if ran for more than a couple years.

 

Plus atomization at low rpm is terrible.

 

Cleaned and modified ones seem to last even less time honestly.

 

I personally would recommend top feed to just about anyone as they just work, and work for the long haul.

 

Just my opinion.

 

Dave

[sIGPIC][/sIGPIC]

Providing unmatched customer service and a Premium level of Dyno/E-tuning to the Community

 

cryotuneperformance@yahoo.com

facebook.com/cryotuneperformance.

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