R33 GTR Lack of Power / Boost Issue

[N155@N]

Hi SAU,

Having boost related issue with my BCNR33. Car is making no boost! Triple gauge is registering vacuum, needle moves from negative to 0kg/cm2. Car drives normally, no sputtering or misfiring. AFRs also reading normal. Acceleration feels normal up until 3500rpm or so where you can begin to feel the lack of grunt. No woosh sounds either, just the sound of the HKS mushrooms sucking air.

Just a little background on the car: HKS2530s, 2.8, E85, VIPEC V88, ~20psi max boost, 4in Exhaust.

Recently had front turbo oil feed replaced by mechanic due to the old one being cracked. Got car back from them on a Sat and it was boosting fine but felt a little underpowered. Didn't drive car again till Wed. This is when is stopped boosting all together. Didn't hear any bang/pop, didn't notice any smoke either. Currently waiting to hear back from mechanic.

In the mean time have inspected piping on both hot and cold sides (also checked FMIC piping behind indicator grilles) for potential boost leak, however wasn't able to find anything loose or hissing. 

Doing a little research on these forums leads me to believe that it could be a blown turbo or a blocked/malfunctioning CAT. All of the posts regarding no boost and blown turbos usually are owners with ceramic wheel turbos, which mine aren't. 

With my limited mechanical knowledge and tools I've taken as much piping as I can to check the turbos. The front turbo looks okay? It spins freely and has no shaft play.

Don't have the tools to check the rear turbo as I can't get that elbow looking thing off to inspect the wheel. I'm yet to inspect the CAT.

Question: If one turbos blown will I be getting half the amount of full boost or just no boost at all? 

Question: What are the chances of the CAT causing the absence of boost? I assume it would have been the ceramic wheels dropping into them. But again, I'm certain I don't have ceramic wheels.

Question: What do you reckon is causing no boost?

 

Appreciate any and all help!

[BK]

1 hour ago, N155@N said:

Question: What are the chances of the CAT causing the absence of boost? I assume it would have been the ceramic wheels dropping into them. But again, I'm certain I don't have ceramic wheels.

Blocked cat it'll still make boost, just very very lazily and probably not peak but it'll still go positive pressure.

1 hour ago, N155@N said:

Question: If one turbos blown will I be getting half the amount of full boost or just no boost at all? 

No boost

1 hour ago, N155@N said:

What do you reckon is causing no boost?

Broken turbo with no turbine wheel or massive split in intercooler piping. Drop your exhaust in front of cat and check it out.

[N155@N]

3 hours ago, BK said:

Blocked cat it'll still make boost, just very very lazily and probably not peak but it'll still go positive pressure.

No boost

Broken turbo with no turbine wheel or massive split in intercooler piping. Drop your exhaust in front of cat and check it out.

Thanks for the reply Ben!

Managed to get a pair of small hands to check if the rear turbo wheel was there and functioning, and much the like the front, it's still there and spinning. 

Don't have the tools and equipment to drop exhaust atm. So as per your advice I proceeded to check intercooling piping for splits, and lo and behold:

Gonna get a new one, fit it and test if that solves it!

[Duncan]

"well, there's your problem"!

pretty sure that counts as a major boost leak. You need to stay off boost until it is fixed, because your turbos will be making eleventy boost at the turbos

[RB335]

Check your engine mounts are good, too much movement may not be good for hoses.

[N155@N]

13 hours ago, Duncan said:

"well, there's your problem"!

pretty sure that counts as a major boost leak. You need to stay off boost until it is fixed, because your turbos will be making eleventy boost at the turbos

Yep! Time to find a replacement! Any suggestions? Waiting for responses from Kudos Motorsports and Vega Autosports. Part number 14463PF / 1446324U00 if you wanna help look hahaha.

Are there any non OEM alternatives? Ex-Japan is looking like its gonna cost north of $300.

 

8 hours ago, RB335 said:

Check your engine mounts are good, too much movement may not be good for hoses.

Was just about to ask this. Thanks mate will have a look! Besides age, what else could have caused this tear?

[Duncan]

It's not clear which one you are after from the pic, but aftermarket silicone will last better

https://justjap.com/products/cooling-pro-silicone-intercooler-hose-kit-nissan-gtr-stagea-260rs-rb26dett

[N155@N]

Just now, Duncan said:

It's not clear which one you are after from the pic, but aftermarket silicone will last better

https://justjap.com/products/cooling-pro-silicone-intercooler-hose-kit-nissan-gtr-stagea-260rs-rb26dett

Yeah that kit should do it. Cheers mate!

Its this one:

[BK]

8 hours ago, N155@N said:

Yeah that kit should do it. Cheers mate!

Its this one:

I probably have a spare. You can have it.

[niZmO_Man]

That's a pretty common one that splits. I drove around for a week while waiting for a second hand one to arrive, just stay off boost haha.

[N155@N]

22 hours ago, BK said:

I probably have a spare. You can have it.

Hey Ben, appreciate the offer but have decided to go with the Just Jap kit. Thanks though!

[RB335]

There is also a N1 version of that hose if a recall, unsure of differences or upgrade