BNR16G Boost surge...

Recently picked up a BNR16G from bryan to replace my vf40 with a stuck wastegate. Well after doing a pull for cryo to tune the turbo we found out i have boost creep. With the wastegate actuator hooked up directly to the compressor housing on the turbo, I am getting upto 19psi of boost(on a 13psi wastegate actuator!) My injectors are maxing out(stock, thats why I got the 16g vs 18 or 20g) and its very unsafe to go over 15psi of boost.

 

Now, my question is, has anyone had any issues like this??? I would hate to spend the money on a EWG setup, because that is exactly why I got the new turbo instead of welding my vf40 wastegate shut.

 

Should I waste my time porting the wastegate, or try to add more restriction in my exhaust?

 

My parts list:

 

Full 3" catless turboback

bnr16g

infamous oil lines

cryotune

perrin inlet

innovate mtxl afr

innovate boost gauge

I never had that kind of problem with my bnr 16g. I had a similar setup to you but with an ebcs. I think you have problems other than the turbo.

what other problems could i possibly have to make a turbo boost like that? Bryan says wastegate is fine(sent him a video.) He did say something about some newer casings having smaller wastegates. Here is the quote:

 

"That looks like normal actuation. The wastegate may need a port job. I did a batch at this time period that had smaller ports. I started porting them a couple months back. 15 psi isn't too much boost but if you want less boost, porting is the solution. If you can tune it rich at 15, it should be okay like that in my opinion.

 

An lower psi actuator will not help."

 

Here are the videos i sent him:

pump to 20psi

close from 20psi

The STI guys have this issue with catless and vf42's swap in a catted downpipe and see if that changes

Yeah I've read numerous wrx and sti boost creep issues, but barely any with a lgt under 400hp. Kind of hesitant to buy a catted 5eat dp for just a possibility of it stopping.

It really seems like you shouldn't have to throw more hardware at the issue. What does your tuner say about the issue?

It appears some of the bnr16gs with the new castings were designed with a smaller wastegate port thus causing boost creep at 0% wgdc. This is a mechanical limitation that's not something that can be tuned around unfortunately.

 

There are only a couple options unfortunately.

 

1. Port the waste gate as Bryan recommends

2. Install new bigger than stock injectors so a proper amount of fuel can be supplied but still have creep and control issues *stock injectors are at 100+ IDC*

3. Install an ewg and have proper control via correct spring pressure

4.try a more restrictive exhaust but no guarantees.

 

Dave

But what guarantee would porting the Wastegate have?

Did a pull for Bryan from bnr with completely disconnected Wastegate. Hit 18psi. Now I'm billowing white/blue smoke. Hoping this piece of shit turbo blew up and not my rings or headgasket.

I am fairly certain you can hit 17-18 psi on stock injectors. I am...

If your turbo had the bnr compressor housing send it in. My injectors max out at 15psi at 5k+rpm. 107% injector duty cycle at that point. leak down testing and compression testing tomorrow then pulling turbo to save time vs just pulling turbo and seeing the inevitable.

Might be going built like you did before if its the rings.

i was thinking of someone else, my bad. But ill be dropping in new pistons after honing if its the rings. Just hoping its the turbo seals that went and not the piston rings. I pulled the intercooler and it was not filled with oil. Will pull downpipe tomorrow.

Did a compression test on the engine pretty much cold and got 90,90,90,91. That was with throttle plate open AND closed, so its probably the shitty harbor freight gauge.

 

After finding out everything was alright, no oil on plugs, no burnt plugs i went ahead and pulled the downpipe. Well pictures will show you the ammount of oil in there AFTER i stuck my hand in there to check it out.

 

Turbo has NO play, but quiet obviously lost a seal. Going to pull it tomorrow, sucks working in the driveway when its raining(been raining since i blew it up, today, and tomorow yay!)

Your comp numbers are low but even.

could be low thanks to a cheap gauge and being tested pretty much cold(didnt want to run it with this much oil burning.)

talked to bryan and he says it might be too much oil going through the turbo possibly. But either way im sending it in so he can check it out and port the wastegate for me. Meanwhile ill try and run my oem vf40 after i find some way to either keep wastegate open, or to align it back again.

on the way to bryan as we speak, should know thursday whether it was something with the turbo(oil leak) or my car/oil starvation.

So sent the turbo out monday, and bryan got it on wednesday. He said somehow the oil "seal" ring ceased. He ported the wastegate, installed new CHRA, and shipped it overnight free of charge for me. Great service! Installing it on Saturday.