Gtx3076 gen2 boost creep

[Eager]

So I got my gtx3076 gen2 v band, I think .83 housing on v-band setup, 6 boost, turbosmart wastegate Installed. 1 bar base spring, it’s a pro-gate lite 50mm on a rb25neo, unopened  

 

on mapping at base pressure it creeps to 1.35 bar. Is this a known trait of them ? 

Had some boost control issues too so need to narrow it down to either the hks controller which is difficult to set, or possibly check that a grub screw has not fell out of one of the ports to block off unused 1/16th npt ports, 

but if I get that sorted I aim to run 1.4 bar through the controller, is that likely to creep too or would that stabilise a bit in that I’m wanting to use that pressure rather than dump it?

i will get some details as I actually get time to go play with the car, left it at that on Friday and actually tuned the creep as a minimum but I want to have a regulated 1.4

Edited June 24, 2018 by Eager

[Dale FZ1]

Got any pics of your gate + piping setup?  Gate takeoff angle and plumbing is a critical aspect to achieving proper control.

Graph showing how boost ramps and what control through the range without BC active would be useful.

Have you spoken with either the fabricator, or your turbo equipment supplier?

[Kinkstaah]

I have had a 6boost and 45mm and 50mm gate in the past, with a 3076, 7670 etc.

Never had creep, so not entirely sure what is going on there, but that setup should be able to hold a nice low boost if you want it to, it is certainly not 'normal'

[KiwiRS4T]

What kind of ECU do you have? You can probably get better boost control with the ecu controlling a Mac valve.

NB wastegate comes off turbo housing

See below - Link + Mac Valve + Synapse 50mm W/G

 

[Dose Pipe Sutututu]

Best to feed a pressure source directly into the gate and see if it hits only gate pressure, if so then there may be an issue with how your vac lines are plumbed up.

[Eager]

Quick pic I have of the exhaust side built up,

im thinking there should be a better angle to the wastegate joined on with a length of pipe? I aim to run 1.4 bar through the hks evc and hoping that may stabalis things, and bring the boost in harder 

 

 

 

currently just on the wastegate as we couldn sort the boost controller but I will sort that and it’s a hks evc 6 controller, on a power fc

Open to all advise lads, thanks

 

[Ben C34]

How much timing are you running?

[Eager]

Unsure mate, I’m not the tuner as such, could grab a pic of the ignition table from the hand commander if helped? What area need I look at

[AngryRB]

Its probably the angle on the gate, as my tuner put it to me, its like cars on the highway trying to make a 90deg turn off, kind of hard to do...

[Eager]

Ye, I’d prefer a small runner pipe up from the manifold wastegate port then mount the wastegate, giving a more direct flow

[KiwiRS4T]

This:

[Eager]

Ye but my turbo or manifold isn’t setup like that

[Dale FZ1]

22 hours ago, Kinkstaah said:

I have had a 6boost and 45mm and 50mm gate in the past, with a 3076, 7670 etc.

Never had creep, so not entirely sure what is going on there, but that setup should be able to hold a nice low boost if you want it to, it is certainly not 'normal'

Greg for interest/comparison, do you have pics of your gate setup?  This may help with conversation here.

A lot of effort went into my 6boost gate takeoff angle but we found measured/logged boost pressure around 6 pounds higher than the rated (and bench tested) weight of the gate spring (50mm Pro Gate).  Boost was steady/consistent, just higher than we expected.  Solution was to run a lighter spring than what the actual target is.  Pragmatic but effective; and lots cheaper than more fabrication work.

[Kinkstaah]

From my for sale thread:

I had the default spring in the 50mm gate, but mine was a progate as opposed to a progate lite, so it was holding about ~9-10psi on gate pressure with a 14psi spring in the thing, on a 2.8L Neo at the time.

I was going to one day up the spring pressure to compensate but 18psi was 400kw at the time so I honestly never really needed to go more, but control at over 18psi was starting to get really wonky with a 9-10psi base spring pressure.

I wasn't really happy with the angle either. Its a T4 TS manifold with an undivided gate. The previous 45mm gate was on the turbine housing done by Scotty here. I was able to run as little as 4psi through that (and up to 25psi with a 4 port). Coming from that, the 6boost felt terrible, but honestly functioned really quite fine in the real world.

[Dale FZ1]

I agree - mine is functional too,  just found it annoying that it the observed boost level so out of whack with the spring rate.

Probably fair to say that with the engine/turbo combinations we really aren't legitimately targeting 1 bar boost though.

[Dale FZ1]

15 hours ago, Eager said:

 I aim to run 1.4 bar through the hks evc and hoping that may stabalis things, and bring the boost in harder 

currently just on the wastegate as we couldn sort the boost controller but I will sort that and it’s a hks evc 6 controller, on a power fc 

Open to all advise lads, thanks

 

 

As per Johnny's comments, you need to make 100% sure the boost control plumbing is correctly hooked up.

That boost graph scale is terrible, but trend seems to be creeping from 3800-4800.  That's where your controller should be doing its thing and bringing up boost (and torque) in that range.

That said, how's it drive right now - does it put power to the ground through that range, or turn tyres?

[Eager]

Hi chaps

 

so tonight I got the exhaust vband released from the turbo and plugged a port on the wastegate, that was meant to be plugged with a 1/16th bung. So up until now I’ve actually just had the controller turned off

however, I’ll now attempt to set the controller over the next few evenings. As for driving, it drives nice, a touch laggy but unless provoked it puts all power to the ground without breaking traction. 

I get what your saying and that’s a fair point? Run a lower rated spring and use the controller to bring it up to 1.4. That may prove to be more steady

i looked at how the wastegate is mounted to the manifold, there isn’t a lot of room on there for a install that allows a more ideal mounting with easier gas flows

[Eager]

To add, I’ll describe my boost control lines if one of you could maybe confirm for me I’m correct ?

its a hks evc 6

on the solenoid, looking down on it, barbs out the top

Right barb, goes to inlet manifold

centre barb reads pressure from nipple on intercooler pipe, also T’d over to stock map sensor and To middle port on wastegate

left barb, goes to end port on wastegate 

 

included a pic of the manual and solenoid as described above

 

 

Can see here the grub screw was missing

now replaced the missing bung 

look ok lads?

 

Edited June 26, 2018 by Eager

[Dale FZ1]

1 hour ago, Eager said:

As for driving, it drives nice, a touch laggy but unless provoked it puts all power to the ground without breaking traction. 

I get what your saying and that’s a fair point? Run a lower rated spring and use the controller to bring it up to 1.4. That may prove to be more steady

i looked at how the wastegate is mounted to the manifold, there isn’t a lot of room on there for a install that allows a more ideal mounting with easier gas flows

It comes down to what you want to achieve with this setup. For me, traction is king.  Some want maximum mid range punch and enjoy the struggle to master throttle/skid control even on dry roads.

My particular setup allows for more/less boost via a dashboard knob, for driveability in various track conditions. (relatively easy process with an ECU that's newer/more advanced than the Power FC).

In your case, I think what you could try is to get that boost controller functioning, and have the boost come up to the targeted value earlier across that 3800-4800 rpm band.  Given that your target is 1.4 bar, and you're getting 1.35 bar from a 1 bar spring, it's probably fit for purpose.

End of the day, a rock steady flat boost curve might look good on a graph, but not give the desired driving experience. It's down to your preference. But play with the controller and see what you like from the result.

 

[Eager]

It’s a grip car so that’s what I’m after, and I’m guessing that progressive way the boost does come in helps that too,

I’ll try get the controller running. Does my plumbing make sense ?

1.4 is my target on 97 Ron fuel but if it seems reliable I’ll possibly try 1.5, i don’t want to forge the engine however so baby steps I guess. What’s the opinion ? On a safe level for a unopened neo