Boost drop

[TampaN54]

I'm new hear searching everywhere for help. No luck yet.

N54, fbo, 17t's, inlets, outlets, port injection, jb4, stage 2+ 535 lpfp, full e85

Just running e85 hybrid port injection off the shelf be flash. Trying to get everything mechanically right before getting a tune.

New parts- injectors, plugs, coils, valve cover, vac lines, I've done several boost leak tests over 25psi with soapy water everywhere. Nothing.

Timing is good, hp lp pumps good. Trims have been a problem but alot better.

The issue- map 2 car holds 17psi boost to redline no problem everytime. Map 7 it holds upper 19psi from 3200 to 5000-5500rpm. Soon as it gets to 5000-5500 it falls on it's face. Boost drops fast to 10-11psi as wgdc shoots up.

I've done this over and over with the same results. I don't understand how it can hold 17psi from 3000-6500rpm no problem everytime. 19.5psi from 3000-5000 everytime but at it falls on it's face at 19psi 5000rpm.

Any ideas/suggestions?

I have jb4 logs. How do you guys like them here. Csv or datazap?

Thanks....

 

[iminhell1]

Put the datalogs here: https://www.spoolstreet.com/graphs/
It's pretty neat.

I'm not a jb4 guy but I would sure think you need a good custom tune to get it working correct.
Stock MAP or upgraded?

 

[P33P33]

I just tuned a car with new DAW turbos.
From the first log I saw there was something off. We tested boost leaks (non existent), all the vacuum lines with new solenoids. Nothing helped. Boost would crash exactly the same as you are describing. Then like after 20th pull rear turbo shaft broke. For reference the boost was 20-22psi but im the first logs with only 15 psi it was already there but harder to see in logs


I haven't seen your log yet but seems very familiar so I would remove your downpipes and take look at your turbos.

Here's a log
https://www.spoolstreet.com/graphs/boost-crash-turbo-failure.6764/?series=2,3,5,22,28,29&zoom=-2,161

 

[TampaN54]

I posted a map 2 and a map 7 log under boost drop.

I've pulled my downpipes to check my turbos twice. Once to look for oil then to check to make sure the wastegates are closing.

I'm not real good at reading graph logs yet but that log looks similar.

Thanks guys

 

[TampaN54]

N20 map sensor

 

[P33P33]

Well, not to ease your struggle my customer also took downpipes off and didn't see anything alarming but the second pull after the visual inspection ended up being the last one

 

[TampaN54]

Well, not to ease your struggle my customer also took downpipes off and didn't see anything alarming but the second pull after the visual inspection ended up being the last one

Yeah. Been waiting for something to happen. This is worse. I can't stand not knowing what's wrong. I've been figuring out these cars for 8 years but not this time......

 

[SlowE93]

Csv ?

 

[TampaN54]

Csv

 

[TampaN54]

I just read RNM's thead about his rear inlet collapsing. Probably the best thing I've heard to check yet. There's a straight coupler middle of my rear inlet that keeps coming loose like it's getting sucked in towards the turbo.

I'm going to go under and investigate. Only thing I'm wondering is if it is only collapsing under higher boost how would I know or test. I'll update after I look.

 

[SlowE93]

I just read RNM's thead about his rear inlet collapsing. Probably the best thing I've heard to check yet. There's a straight coupler middle of my rear inlet that keeps coming loose like it's getting sucked in towards the turbo.

I'm going to go under and investigate. Only thing I'm wondering is if it is only collapsing under higher boost how would I know or test. I'll update after I look.

This is possible as its happened to a few people already. The inlets were VRSF without the wire to reinforce the inlet, if not mistaken.
If you have VRSF silicone inlets, I would check to see if you have the wire or not. Easy to check.

 

[TampaN54]

This is possible as its happened to a few people already. The inlets were VRSF without the wire to reinforce the inlet, if not mistaken.
If you have VRSF silicone inlets, I would check to see if you have the wire or not. Easy to check.

I have vrsf relocated inlets they have a 45 degree coupler on the rear turbo I know is not reinforced at all. We'll see soon.

 

[SlowE93]

I have vrsf relocated inlets they have a 45 degree coupler on the rear turbo I know is not reinforced at all. We'll see soon.

The ones I have heard collapsed were factory location....but yes, we will see. Let us know what u find.

 

[SlowE93]

 

[TampaN54]

Well pretty sure I found it. My rear inlet coupler is deformed down to maybe an inch wide. It was almost impossible to get a picture but maybe you can see it. I'll get better pictures when I pull the downpipes this weekend.

 

[TampaN54]

This was a big clue. This coupler kept getting sucked in towards the turbo. I could never figure out why. Now I know.

 

[SlowE93]

Well pretty sure I found it. My rear inlet coupler is deformed down to maybe an inch wide. It was almost impossible to get a picture but maybe you can see it. I'll get better pictures when I pull the downpipes this weekend.

Probably gets sucked in under boost

 

[TampaN54]

Probably gets sucked in under boost

All makes sense now.

 

[TampaN54]

Now the dilemma is how to fix it. Don't know if there's stronger 90 degree couplers?

 

[SlowE93]

Now the dilemma is how to fix it. Don't know if there's stronger 45 degree couplers?

Im sure there is reinforced with wire