Over 700 whp 335is but too much lag. Making 25 psi above 5300 rpm 3rd gear. Late spool up issue

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JMVELA

Private
Mar 17, 2018
32
Hi! I have been tuning my car with a good tuner for over 3 years. We have made a lot of custom maps and I am really happy with my tuner.
Since I installed the MMP BB turbos (custom 48 mm dual BB turbos which are making a ton of power) which I installed last December, I have noticed that these are too laggy to what I would like. Don't know if you guys here could help and assist, but I have ask my tuner for several revisions, which he has agree to do, but even though we have tried we could not find a way to obtain a decent spool up on these turbos. Could it be tune related issue?? or could it be a exhaust manifold design issue?? I ask for the manifold issue because I have read about some others using MMP manifold and reporting on having apparent similar issues. Please don't start trash taking about MMP, because this is not the intend of this post. Mauricio has been very helpful with me and he is always willing to help and assist (so he did not deserve trash talking in this post at least). His turbos are making a lot of power on my car (so far 719 whp @29 psi 93 oct and meth PI) and have lasted more than the other brand I have used in the past with this amount of power.
Your help and assistance in this spool up issue will be greatly appreciated.

I have attached three logs for reference. The first one I had the FF set to 32. The other two I had the FF set to 40 which help on spool up a bit, but then it over boots at high RPM. I am using JB4 in case someone that could care to help and assist would need to know.

Regards

PS there are no boost leaks. Have look for this a lot of times.

 

Rob09msport

Major
Oct 28, 2017
1,847
Monroe CT
Those are really big turbos and I think they may be to big I mean 15t spool at 3000 and reg 1ks closer to 4k. You gotta realize your making 18 psi earlier on but asking for close to 30 psi is alot. Many do say how the manifold is to big for n54 head. You prob should look into cams and porting or n53 head. Your making ton of power on pump so I assume the motor is healthy. Your cheapest route may be to change turbos.
 
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JMVELA

Private
Mar 17, 2018
32
Those are really big turbos and I think they may be to big I mean 15t spool at 3000 and reg 1ks closer to 4k. You gotta realize your making 18 psi earlier on but asking for close to 30 psi is alot. Many do say how the manifold is to big for n54 head. You prob should look into cams and porting or n53 head. Your making ton of power on pump so I assume the motor is healthy. Your cheapest route may be to change turbos.

Thanks! Yes, I have think on adding a new head to my engine. Could be my next upgrade. Not sure yet if would pull the trigger on this.

On changing my turbos, I don't think would be an option for me at this time. These turbos, once they hit, the game change. :)

Thanks for helping my friend!!
 

Rob09msport

Major
Oct 28, 2017
1,847
Monroe CT
Contact omar @Hydra Performance he has the most comprehensive head setup for Fair price
Check out his build thread on here. You will spool faster and make more power with less boost and run easy 8k rev limit so your powerband should pretty much be twice as wide.
 
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ShocknAwe

Lieutenant
Jan 24, 2018
815
SC
Contact omar @Hydra Performance he has the most comprehensive head setup for Fair price
Check out his build thread on here. You will spool faster and make more power with less boost and run easy 8k rev limit so your powerband should pretty much be twice as wide.
Not sure I would recommend the N53 head by Hydra for the MMP turbos he has. Maybe if switching over completely to the full Hydra HP800 setup but then you're talking about major expense since he already has functioning turbos which have been installed...

I think porting the N54 head will be best in this case to allow the same power at lower overall peak pressure. Add some ethanol to spool faster, or race gas, PI meth, a few options.

Big turbos spool slower, especially if choked.
 

Rob09msport

Major
Oct 28, 2017
1,847
Monroe CT
I think that's bmw thinking we gotta remember how simple some of this is I dont see why the mmp couldnt be adapted to fit. They have the large runner or hydra could adapt his manifold to the mmps no prob. Cheapest fix would be a 50 shot. But I think mmp runners are just to big even for ported n54. He would have amazing build with proper manifolds , you just cant change size pre trubsky like the way they do now
 
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JMVELA

Private
Mar 17, 2018
32
Contact omar @Hydra Performance he has the most comprehensive head setup for Fair price
Check out his build thread on here. You will spool faster and make more power with less boost and run easy 8k rev limit so your powerband should pretty much be twice as wide.

The issue here is that I have DCT trans, for now we can't increase RPM limit. We can only rev to 6700 rpm. So far I do not know if there is any option to increase rpm limit over 6700
 

tisdrew

Corporal
Jun 27, 2017
138
Every report of these turbos I've seen is that they're laggy -- I don't believe this can be fixed with tuning. As others have hinted at, headwork is a solution but it is expensive and uncharted territory. A n53 head will be more of a headache than anything because the exhaust ports/manifolds will no longer match up. Cams might help flow but typically bigger cams = less power down low, the exact thing you're asking for. I think the real solution that's budget-friendly is a 50 shot as someone else recommended. I hear ABR builds stroker motors if money isn't a concern
 
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ShocknAwe

Lieutenant
Jan 24, 2018
815
SC
Just get a reputable single 6266 kit and don’t look back. More power, better spool (with good tuner), and RELIABILITY with no need for N53 head projects and $1,500 cams!
Agree that it's the easier way to go, but I remain unconvinced it's the proper way to set up this native 3.0L TT-I6. Then again, not like I'm unbiased.
 

Torgus

Captain
Nov 6, 2016
1,379
Boston
As said above add a shot or change your turbos are the only things that will likely help you. 3L is not a ton of displacement and you are rev limited. If you could rev to 8200 you would have a decent power band.

If you are unconvinced try a different tuner but I doubt the results will change much if at all.
 

JMVELA

Private
Mar 17, 2018
32
As said above add a shot or change your turbos are the only things that will likely help you. 3L is not a ton of displacement and you are rev limited. If you could rev to 8200 you would have a decent power band.

If you are unconvinced try a different tuner but I doubt the results will change much if at all.
Thanks!

Right now I am very pleased with my tuner!! The only downside is the spool up, but once it spool the car feels good
 

335is02

Specialist
Mar 10, 2018
94
Thanks!

Right now I am very pleased with my tuner!! The only downside is the spool up, but once it spool the car feels good
Single mass flywheel might help with faster rev might want to look into that see if it might help you out.
 

JMVELA

Private
Mar 17, 2018
32
Single mass flywheel might help with faster rev might want to look into that see if it might help you out.

Yep, already have this upgrade done to my car. The best part is that the flywheel eliminated the ignition cut at 6300 rpm I was having for apparent noise the dual mass flywheel produced.
 
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MoreBoost

Corporal
Jul 27, 2017
224
I'm a JB4 user for 5 years. You can send me a log to take a look at.
Things like antilag can help spool up faster. Duty bias on the JB4 is useful to give the turbos quicker spool up.
I'm sure your tuner knows this. I too was thinking the nitrous shot would be good.
 

JMVELA

Private
Mar 17, 2018
32
I'm a JB4 user for 5 years. You can send me a log to take a look at.
Things like antilag can help spool up faster. Duty bias on the JB4 is useful to give the turbos quicker spool up.
I'm sure your tuner knows this. I too was thinking the nitrous shot would be good.
 

carabuser

Lurker
Oct 2, 2019
12
Try contacting Jake (jyamona). I remember reading some posts by him claiming to have some secret VANOS sauce for faster spool on larger turbos. If you are still running the stock VANOS (spool) tables then it's no surprise that it's laggy.
 
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Rob09msport

Major
Oct 28, 2017
1,847
Monroe CT
The issue here is that I have DCT trans, for now we can't increase RPM limit. We can only rev to 6700 rpm. So far I do not know if there is any option to increase rpm limit over 6700
Dyzeak did full m3 software and egs which then allowed gts flash ,adj launch control etc. That would allow raised rev limit
 
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