MHD V10 Stage2+ targeting 22psi on stock turbos?

[Aidan335DCT]

datazap.me | Aidan335DCT | Log 1692269951

datazap.me

Hi guys,
Having done some datalogs recently im quite concerned.
The MHD site says that their stage 2+ should try hit around 18psi then taper to 14, but as seen in this log, mine seems to be hitting about 19 then tapering to 12. What concerns me more is the gap between the target PSI and the actual boost. At peak, its targeting nearly 22psi and hitting 19.3 but towards redline its targeting about 16 but hitting 12.
I've got 0 fault codes so that kind of rules out a boost leak, least not one large enough to throw a 30FF. Unless maybe the stock DV or PCV is leaking boost without it being large enough to trigger a fault?

Specs are:
335i DCT
99 RON fuel (93 oct)
MHD v10 stage 2+ 98 RON
3" catless DP
Forge CP with stock DV
DCI
FMIC
stock turbskies

 

[pbondar]

Could just be the turbos getting tired and running out of puff..?

Here are my v10 stage 2+ logs on 98 ron at 65k miles

Z4 E89 35is V10 stage 2+ first attempt at data logging prior to fitting TTE500 turbos

www.spoolstreet.com

 

[Aidan335DCT]

Could just be the turbos getting tired and running out of puff..?

Here are my v10 stage 2+ logs on 98 ron at 65k miles

Z4 E89 35is V10 stage 2+ first attempt at data logging prior to fitting TTE500 turbos

www.spoolstreet.com

View attachment 85442

yeah that would make sense, they're still hitting 19psi at peak boost which im happy with. Doesn't explain why the MHD map is targeting so high tho

 

[pbondar]

They are just asking the turbos to give all they can give…..you can see on the dyno how they run out of puff on the top end..

 

[Aidan335DCT]

They are just asking the turbos to give all they can give…..you can see on the dyno how they run out of puff on the top end..View attachment 85451

ah okay, im still gunna upgrade the PCV and DVs for peace of mind. Then might join you in the TTE500s when my stock turbos eventually kick the bucket

 

[That4chanhackerguy]

Keep in mind boost target is not actaully what boost its aiming for.... boost target is basically boost max before intervention since if you meet or exceed that target the car will modulate the throttle and may trigger a torque limiter as well.

 

[SlowE93]

Keep in mind boost target is not actaully what boost its aiming for.... boost target is basically boost max before intervention since if you meet or exceed that target the car will modulate the throttle and may trigger a torque limiter as well.

Interesting.
So what is boost aiming for if not the target ?
Most everyone I know tries to dial in a car within 1 psi + or - of actual target or less.
Including myself.
Please don't say load as that ...nevermind.
Curious tho.

 

[Torgus]

boost target is basically boost max before intervention since if you meet or exceed that target the car will modulate the throttle and may trigger a torque limiter as well.

Sounds like the car is 'targeting' a certain numerical value of boost at certain RPM setpoints...

 

[pbondar]

ah okay, im still gunna upgrade the PCV and DVs for peace of mind. Then might join you in the TTE500s when my stock turbos eventually kick the bucket

Well the TTE500s transform the way the engine feels as they match then eclipse the V10 tune and just sing on..contrary to common view that twin turbos run out of puff at the top end..wonderful..

 

[pbondar]

Remember the V10 tune is a broad spectrum tune…not a custom tune ..given the various stages of decay of the OE turbos they are just asking for as much as they can given that most turbos will be getting tired..

 

[carabuser]

Keep in mind boost target is not actaully what boost its aiming for.... boost target is basically boost max before intervention since if you meet or exceed that target the car will modulate the throttle and may trigger a torque limiter as well.

Boost target is exactly that, the target boost.

The BMW documentation actually refers to that parameter as "target manifold pressure".

The intention should always to be as close to target as possible but often with hybrids you start to deviate up top unless you taper the target.

 

[Torgus]

Boost target is exactly that, the target boost.

The BMW documentation actually refers to that parameter as "target manifold pressure".

The intention should always to be as close to target as possible but often with hybrids you start to deviate up top unless you taper the target.

This.

 

[SlowE93]

This.

Is what we been sayn.

Still awaiting a response as to why it is not.