F8X G30-770 N55 M2 Boost Control Options

[ChrisD]

I've got a 2016 N55 M2 that's currently stage 2 but later this year I'm going to make a top mount turbo setup for it.

At the moment my plan is:

• G30-770 with 1.01AR (might also order a 0.83 AR to test)
• Turbosmart 50mm wastegate
• Dorch DS25 HPFP
• CSF intercooler
• CSF radiator
• 1 step colder spark plugs
• S63 EU5 injectors
• Aluminium intake pipework with BOV
• Vargas crank hub upgrade
• Aiming for 600-650 bhp, stock engine internals
• 99 RON UK pump gas (no meth)

I made a twin turbo setup for a 350Z in the past so I'm comfortable fabricating the turbo manifold, intake pipework, and making AN lines etc myself but one thing I'm a bit unsure of for this platform is boost control. So yeah the main point of this post:

Someone on another forum with a big turbo N55 said that they had issues with an external wastegate and went back to using the stock electronic wastegate but I'm not really sure how that's possible with a non factory turbo. There was also an old thread on here where someone mentioned the only option for external boost control was the Motiv Reflex+ control unit but that seems pretty overkill just to control a boost solenoid rather than for port injection etc which seems to be its main purpose. Is that still the only option?

Can the stock ECU with Ecutek or BM3 really not control a 3 port MAC solenoid?

Also, are there any other potential issues you guys see with my plan or other supporting mods that I need to look into? Maybe the power goal is unrealistic without meth or a LPFP upgrade?

Thanks
Chris

 

[wheela]

You can get the g30-770 with internal wastegate, and Full-Race makes a bracket for it that let's you control it with an electronic wastegate actuator:

Full-Race Electronic Wastegate Conversion Kit - Garrett G30 & G35

Precisely control your boost! The Full-Race eIWG Electronic Internal Wastegate Conversion Kit for Garrett G30 & G35 turbos replaces the traditional boost-activated wastegate actuators. The electronic actuator allows for precise control of the turbocharger wastegate in all conditions.

www.full-race.com

 

[ChrisD]

You can get the g30-770 with internal wastegate, and Full-Race makes a bracket for it that let's you control it with an electronic wastegate actuator:

Full-Race Electronic Wastegate Conversion Kit - Garrett G30 & G35

Precisely control your boost! The Full-Race eIWG Electronic Internal Wastegate Conversion Kit for Garrett G30 & G35 turbos replaces the traditional boost-activated wastegate actuators. The electronic actuator allows for precise control of the turbocharger wastegate in all conditions.

www.full-race.com

Thanks for the tip! Unfortunately I already have the turbo and its not the version with the internal WG, plus I'm a sucker for a screamer pipe

 

[wheela]

To hit your power goals with that turbo I think you'll need either e-mix or meth to supplement your 99RON. I'm not sure where you'd end up on 99 RON only, but I'm guessing it may run out of octane around 450-475 whp? Just a guess, I haven't seen amy n55 numbers on that turbo, so going from what I've seen on similar sized units.

 

[wheela]

Thanks for the tip! Unfortunately I already have the turbo and its not the version with the internal WG, plus I'm a sucker for a screamer pipe

Shoot, I guess e-wastegate is out then!!

 

[wheela]

Kind of pricey, but you can get different housings only, if you decide to stick with e-gate.

 

[wheela]

I'm in the same boat with controlling an external wastegate. I don't want to add any boost controllers, so I decided to do something unorthodox to directly control it with my DME. I haven't seen anybody do this yet, so I'll be the guinea pig. If you're interested in what I'll be doing, check out post #207 on page 11 of my build thread for details:

Edit: actually scratch that, I'm pneumatic wastegate, so what I'm doing may not work with a DME set up for electronic wastegate.

Speedtech EFR 7670 on e84 X1

Ayeee we love to see the progress. I gotta come see this in person soon. Haven’t been in MN as often lately. As for my car, I’m still lost, but it’s snowing back home anyways. Can’t drive on PS4S’s in the snow😭 Thanks! For sure, it's mostly a pile of parts at this point but slowly making...

www.spoolstreet.com

 

[ChrisD]

To hit your power goals with that turbo I think you'll need either e-mix or meth to supplement your 99RON. I'm not sure where you'd end up on 99 RON only, but I'm guessing it may run out of octane around 450-475 whp? Just a guess, I haven't seen amy n55 numbers on that turbo, so going from what I've seen on similar sized units.

I guess I'll just have to see how far we can push it and if it gets nowhere near then I'll have to look at meth but yeah really not keen on having to constantly buy and store and top up meth. No access to E85 around me either.

Seeing your results testing the boost solenoid with factory ECU was interesting, thanks for posting those. Helps me understand why we can't just control it with the stock ECU.

I guess I'll have to get something like the GFB G Force 3 or the Motiv Reflex. The GFB is cheaper and simpler but doesn't seem like it has any way to take throttle position or anything else into account. The Reflex has inputs for RPM and intake cam so I'm hoping that would give my tuner a bit more control over how the boost is managed.

 

[wheela]

Glad to see another big turbo n55 in the works, I'm excited to see how your build comes together

Hopefully some of the n55 guys on here running conventional wastegates will chime in with what they've done. I know @houtan runs a GFB3 and I believe he's pretty satisfied with it.

 

[houtan]

Looking forward to seeing your progress.

As @wheela menrioned, I am running a gfb3 to control my Mac/ boost. I absolutely love it for its simplicity and ability to switch boost target on the fly. My tune is set up to run wastegate boost (13.8ish psi) all the way to full boost (27ish psi). Usually I’m driving around at wastegate boost, but I can change to 6 other boost targets at the push of a button.

The setup for the gfb is really simple and there are not a lot of settings to adjust. But it handles everything really well once it’s set, at least for my turbo.

Here is my thread that shows some of my progress:

Pure Turbos Stage 3 (PS3) dyno results for N55

Finally! I got on the dynojet at EAS in Anaheim, CA on 4/28/2022 to get some numbers on the PS3. It took a while, but I am happy I can finally share results with everyone. Before I get into the details I wanted to mention a couple of things up front: A big thanks to Pure Turbos for releasing...

www.spoolstreet.com

There is another stand alone ebc, turbosmart ebc 2, that I believe allows you to set up boost by RPM intervals and I believe it also has map switching. Best way to confirm is just look at the instruction manual. I know member @onedirty5 is running this boost controller and is happy with it. Also I believe the fastest n55 so he may have good information running a big turbo.

Here is a video of how I switch boost on the fly:

 

[ChrisD]

Looking forward to seeing your progress.
...

Thanks for the real world experience info, much appreciated. Good to know that the GFB works well enough and is definitely an option I can consider. Enjoyed reading your build thread too!

 

[CalvinNismo]

Interested to see how you do with this. My hunch is the G30-770 will be a bit small to reach those numbers on pump fuel, but your M2 will still be moving I’m sure. Super unleaded plus meth’, I’m positive you’d hit your target. Depends if you want that.

The other option if you can make the room for it is the Turbosmart StraightGate which VTT offer with an adapter for the factory electronic wastegate. If it does what it says on the tin it could be ideal, though pricey. No affiliation, I’ve just seen it as an option.

https://vargasturbo.com/product/vtt-dcs-ewg-control-system-for-turbosmart-straight-gates/

 

[ChrisD]

To hit your power goals with that turbo I think you'll need either e-mix or meth to supplement your 99RON. I'm not sure where you'd end up on 99 RON only, but I'm guessing it may run out of octane around 450-475 whp? Just a guess, I haven't seen amy n55 numbers on that turbo, so going from what I've seen on similar sized units.

Funnily enough whilst reading through @houtan build thread just now, I saw a random comment from someone saying they made 500 whp on this same turbo but that was with meth (although not sure what AR they were running).

So yeah maybe I need to scale back my expectations on pump gas. I just figured as I made over 600 bhp (560 whp I think it was) on my 350Z purely on pump gas, and that was using two tiny turbos (GT2554R), then one big turbo should be able to do similar on this platform especially with the newer G series turbos. To be fair though the 350Z engine was 3.5L vs our 3.0L and of course there's plenty of other differences too.

Either way I'm still excited to get started on this project once I've done my last track day of the year in late September

 

[ChrisD]

Interested to see how you do with this. My hunch is the G30-770 will be a bit small to reach those numbers on pump fuel, but your M2 will still be moving I’m sure. Super unleaded plus meth’, I’m positive you’d hit your target. Depends if you want that.

Yeah tbh I think I was maybe a bit too worried about lag, having only had experience with very small turbos before (see previous comment) and maybe I should have gone for a slightly bigger turbo.

The G30 770 I have has a 1.01 AR and I was considering ordering a 0.83 AR in case the 1.01 was too laggy but maybe I should actually be considering ordering the 1.21 AR instead? I'd love to try all 3 but that's going to get too expensive for 2 turbine housings I'll never use again. To be honest I'm not even sure if larger AR would help in this scenario? I know in theory they make more power at the top end and spool up a little slower, but will that do much in this scenario where the entire turbo might be a bit too small?

But yeah what do you guys think, if I have to only order 1 extra housing to test against the 1.01 AR, should it be the larger one or the smaller one? It will be a street car that does the occasional track day, no drag strips etc

 

[CalvinNismo]

If you’re not yet 100% set on building yourself a top mount, it may be worth considering one of the cast replacement hybrids (the new Pure 600, Pure 750, that sort of thing) just for ease. They would likely achieve similar numbers on pump fuel to what a G30-770 might make for less hassle (and less money). Not trying to put you off doing it though! A tubular manifold has the potential to sound immense and you could have even better response with a ball bearing turbo. It’s just normally people go full frame when they exceed the power that the ‘drop in’ offerings can offer.

My VTT GC has a 58mm inducer and likely based on the Garrett, I don’t have it running yet though. I’ll be sure to post results when I do, glaciers move faster than my car at the moment though!

I’d leave the CSF radiator if you haven’t bought it yet. Go do88 instead. It’s a long thread but the gist is (for the N55 M2 at least) do88 stuff works and CSF stuff doesn’t.

N55 Extreme Engine Cooling

N55 Extreme Engine Cooling

f87.bimmerpost.com

 

[CalvinNismo]

I know member @onedirty5 is running this boost controller and is happy with it. Also I believe the fastest n55 so he may have good information running a big turbo.

If he isn’t right now, it won’t be long before he is.

 

[ChrisD]

If you’re not yet 100% set on building yourself a top mount, it may be worth considering one of the cast replacement hybrids (the new Pure 600, Pure 750, that sort of thing) just for ease. They would likely achieve similar numbers on pump fuel to what a G30-770 might make for less hassle (and less money). Not trying to put you off doing it though! A tubular manifold has the potential to sound immense and you could have even better response with a ball bearing turbo. It’s just normally people go full frame when they exceed the power that the ‘drop in’ offerings can offer.

I appreciate the suggestion but nah its fine, the main reason for doing it is for the fun/challenge of fabricating it and having a top mount... maybe even with a silly bonnet exit screamer pipe (not everyone's taste I know). I know its simpler to just drop a Pure750 in there but I like making things myself.

Here's my other project for reference:

This is a track only 370Z drift car that I've still not finished but I used those same turbos and same built engine in my 350Z drift car and that made 560 whp and was good fun. I made the turbos bottom mount on the 350Z and regretted it as it was such a nightmare to work on and was a 2 man job to even mount one of the turbos to the manifold. So yeah definitely want to go top mount and definitely up for making a tubular manifold... although if space ends up being as tight as I think it might be then I might have to resort to just making a log manifold. We'll see once I get things stripped down and make a start in September/October

Btw I don't think you're right about pure750 costing less money. Maybe if you were getting all the work done by someone else it might, but I'd say in total I've spent about 60% the cost of the pure750 so far and I've bought almost everything I need (turbo, wastegate, manifold flange, stainless pipe, V bands etc). That was also one reason for going down this route in the first place.

 

[wheela]

Wow, nice work!!

 

[wheela]

Yeah tbh I think I was maybe a bit too worried about lag, having only had experience with very small turbos before (see previous comment) and maybe I should have gone for a slightly bigger turbo.

The G30 770 I have has a 1.01 AR and I was considering ordering a 0.83 AR in case the 1.01 was too laggy but maybe I should actually be considering ordering the 1.21 AR instead? I'd love to try all 3 but that's going to get too expensive for 2 turbine housings I'll never use again. To be honest I'm not even sure if larger AR would help in this scenario? I know in theory they make more power at the top end and spool up a little slower, but will that do much in this scenario where the entire turbo might be a bit too small?

But yeah what do you guys think, if I have to only order 1 extra housing to test against the 1.01 AR, should it be the larger one or the smaller one? It will be a street car that does the occasional track day, no drag strips etc

Aa far as AR goes, I don't think you'll have spool problems with that turbo and the 1.01, and going smaller will limit your power potential up top. I'd probably save my money and not order an additional housing until you can try out the 1.01 and see if it spools good enough for you. Then if you feel you've got some spool to spare, you could try the larger AR to get a little more power up top.

 

[CalvinNismo]

I appreciate the suggestion but nah its fine, the main reason for doing it is for the fun/challenge of fabricating it and having a top mount... maybe even with a silly bonnet exit screamer pipe (not everyone's taste I know). I know it’s simpler to just drop a Pure750 in there but I like making things myself.

Btw I don't think you're right about pure750 costing less money. Maybe if you were getting all the work done by someone else it might, but I'd say in total I've spent about 60% the cost of the pure750 so far and I've bought almost everything I need (turbo, wastegate, manifold flange, stainless pipe, V bands etc). That was also one reason for going down this route in the first place.

Fair play, I was hoping you’d say you were gonna fabricate it anyway. I’m looking forward to seeing what you come up with! Whereabouts in the UK are you?