Rb25 Neo Gt3076 Issue

[lusunt]

Hi all just seeing what people's thoughts are and what may be the cause....

I got a rb25 neo with a gt3076r.82 and I'm not getting full boost until 5500rpm...feels way too laggy for me and from my research and what other people have said it shouldn't be so laggy either. I've just brought a .63 rear housing to get better response (not fitted yet) but I feel like it shouldn't be so laggy anyway and maybe there's an underlying issue?? Setups currently making 340kw @17psi.

Some of the Mods are:

New neo engine

Plazmaman plenum

1000cc injectors

Rb26 covers -12 breathers

52mm rad

600x300x100 fmic

One piece cooler pipping

Fpr

6boost top mount

Gt3076.82

Haltech platinum pro

Edited March 10, 2015 by lusunt

[Ben C34]

That's ridiculous.

Check cam timing.

Edited March 10, 2015 by Ben C34

[KiwiRS4T]

340Kw is pretty impressive. Can you post your dyno chart(s)?

Stock cams?

VCT working?

[lusunt]

Yeh I havnt done any of the work myself this time....my tuner/mechanic has.

Havnt got results printed or anything waiting till I'm completely happy and finished

Edited March 10, 2015 by lusunt

[zebra]

  On 10/03/2015 at 10:13 AM, KiwiRS4T said:

340Kw is pretty impressive. Can you post your dyno chart(s)?

Especially at 17psi

[lusunt]

Stock internals vct isn't hooked up I don't think

Edited March 10, 2015 by lusunt

[lusunt]

Sorry it's only got acl bearings arp head studs? metal head gasket from memory

[zebra]

  On 10/03/2015 at 10:15 AM, lusunt said:

Stock internals vct isn't hooked up I don't think

That is 90% of the problem

[lusunt]

  On 10/03/2015 at 10:19 AM, zebra said:

That is 90% of the problem

As in vct not hooked up? I was told it doesn't matter at all....

[zebra]

Then you need to find a new mechanic/tuner

[lusunt]

Can you elaborate a bit for my own knowledge cos I tried looking into that too but couldn't find anything that matched my issue.....

[Kinkstaah]

It matters, a lot. Not as much as you'd get this result though, there's more than just that at play..

I also vote there's some massive boost leak somewhere too, for bonus points

[lusunt]

  On 10/03/2015 at 10:27 AM, Kinkstaah said:

It matters, a lot. Not as much as you'd get this result though, there's more than just that at play..

I also vote there's some massive boost leak somewhere too, for bonus points

Is there something I can buy that reliably tests for boost/vacuum leaks?

[jay-rod]

Goto bunnings, get some pvc end caps, put a hole in it and hook up a air compressor.
Pump it upto ~25 psi.

[lusunt]

Still wouldn't mind any other thoughts.....

[jay-rod]

Getting VCT working should be a priority, unless you don't have stock cams?
I believe it will give you about 200rpm more response compared to off.
I would be PM Stao from hypergear and see if he will give you some tips.

The .62 housing will prob get you about another 500 rpm response.
Is it running internal gate?
Try pre loading the actuator

Edit,

Oh yeh, a china spec 3076 will do this

Edit again

340 kw with a gt3076 and only 17 psi? That doesnt seem right?
are you on E85?

Edited March 10, 2015 by jay-rod

[KiwiRS4T]

I agree. Get another mechanic/ tuner.

VCT changes the cam timing by... I think its 20 degrees... so you can see it's not insignificant.

[lusunt]

  On 10/03/2015 at 11:34 AM, jay-rod said:

Getting VCT working should be a priority, unless you don't have stock cams?

I believe it will give you about 200rpm more response compared to off.

I would be PM Stao from hypergear and see if he will give you some tips.

The .62 housing will prob get you about another 500 rpm response.

Is it running internal gate?

Try pre loading the actuator

Edit,

Oh yeh, a china spec 3076 will do this

Edit again

340 kw with a gt3076 and only 17 psi? That doesnt seem right?

are you on E85?

Well my thoughts were that it should hit full boost at around 4000rpm 4400 at latest

if vct only effects it by a couple hundred rpm then I'm not fussed about using it...

Sorry it's

45mil turbosmart External gate

Genuine gt3076

and yeh e85

Edited March 10, 2015 by lusunt

[jay-rod]

Then dont use it, but if you have a neo engine with neo cams, why the hell wouldnt you?
No negatives, only positives???

But yes every 3076 i see has full boost by ~4300 on a rb25

Gate could be causing slow boost, do you have a dyno graph with correct scaling?
Would help out most people here diagnoses issues

Edited March 10, 2015 by jay-rod

[lusunt]

Very true. Seems kinda minor at this point in time though unless someone thinks otherwise....

It's just at the moment I want to focus on the main issue...getting it to come on properly....