[vrships]

I am not sure why this is not discussed widely before. I may have seen some posts mentioning in the m340 forum, but only slightly related

TLDR:

For those that have Bootmod3 and stage 2 or higher engine tune, you may really need the XHP to lift the torque limit to fully harvest the additional power. If you don't, the torque is gonna be limited <550nm all the way (under LC, it's even <500nm), while stg2 torque can easily go beyond 620nm.

=============================
Before XHP, I had been running stage 2 93 on a 2020 model for a few weeks. One thing I noticed is that the boost target and boost, when doing a 3rd gear WOT pull, was only around 16-17 psi at < 6000 rpm. This is as low as the stock boost, and much lower than the ACN91 boost (which is all the way >20 and boost target is 22.4). I was confused why stg 2 93 was so much more conservative than stg 1 ACN 91. It made no sense to me.

Although with stg 2 93 the car certainly runs faster, but the displayed "torque actual / target after clutch" is merely <550nm, while the torque predrivedynamics is 670nm. This is abnormal since with stock tune or ACN91 stg 1, these 3 torque values are within 30 nm different. Also these estimated torque values should be relatively accurate when compared between maps, meaning a 20% gain in these values should reflect on a real dyno run.

The facts are implying that the engine held up power somehow while it could do much better. I have asked ptf but they didn't find anything wrong, or explain the reasons why torque is limited

https://www.bootmod3.net/log?id=65dd...bc901ce26e3fe6
======================

And then I installed the XHP. I didn't even purchase the TCU map and was just trying out basic settings to fine tune shift behavior. And then immediately I did a BM3 stg 2 93log with updated XHP settings, and the car felt obviously faster. Upon checking the log I realized now the torque can easily go above 550nm, reaching 650nm easily. And boost target was right on at a constant 22.4 with actual boost 21-23 mostly.

I then did a 0-100 pull. Guess what, even with the wet road under the rain and an entire wheel spinning 1 st gear, it did 0-100 (62mph) in 3.68s, easily beating smoking the fastest time I did before XHP on perfect road 3.97s.

https://www.bootmod3.net/log?id=65e5...912436fb2ff41a

Now things make sense. Somehow the BM3 stg2 93 map did not remove the torque limit inherently from ZF8HP51. It achieved this by pre-calculate how much boost it should reduce, and apply the different boost target curve when you do the pull. Every pull is very repeatable and you won't find a sign that it cuts off power abruptly because DME redefines the curve in advance.


So it is still confusing why PFT did not make a simple switch in BM3 so you can switch off the global or by gear torque limit (it does allow you to further REDUCE torque, though). From what I know, if you get a custom tune, your tuner should be able to control if the torque limiter is active, and for that reason, a lot of people sing custom tune do not need to resort to XHP to release the hidden torque.

If you stick with OTS BM3, this is a must If you want to use true stage 2 or even Ethanol maps. And maybe this is B58TU specific issue? But anyway if not for XHP I would never realize what the true power of BM3 OTS map.

[suby01]

Cool write up. So you need XHP with BM3 OTS. But my custom tune does not.
What B58 engine code do you have on your 2020?

[AshtonPJT]

You really need xHP on both, when you bypass those torque limits on the trans it can cause traction control and a few other things not to properly.

[vrships]

Originally Posted by suby01

Cool write up. So you need XHP with BM3 OTS. But my custom tune does not.
What B58 engine code do you have on your 2020?

I think so. Not sure there is other easier waysto disable the torque limit for OTS maps. After all, not so many people daily log WOT pulls to discover this...

In BM3 it's listed as B58-TO-D. Not sure what code type this is . It is commonly referred to as B58M30O1, the one with 382hp rated.

[suby01]

Originally Posted by vrships

I think so. Not sure there is other easier waysto disable the torque limit for OTS maps. After all, not so many people daily log WOT pulls to discover this...

In BM3 it's listed as B58-TO-D. Not sure what code type this is . It is commonly referred to as B58M30O1, the one with 382hp rated.

Okay ya same as mine.

[suby01]

Originally Posted by AshtonPJT

You really need xHP on both, when you bypass those torque limits on the trans it can cause traction control and a few other things not to properly.

Right on. I haven’t adjusted anything on XHP. Just stage 3. Set it and forget it. Summer setup and maintenance coming in a few weeks.

[vrships]

Originally Posted by suby01

Right on. I haven’t adjusted anything on XHP. Just stage 3. Set it and forget it. Summer setup and maintenance coming in a few weeks.

Did you have a chance to test 0-60 or 1/4 mile? I wonder if those ~100ms save between shifts can benefit the times.
bTW, what oil do you use after you got the tunes?

[suby01]

Originally Posted by vrships

Did you have a chance to test 0-60 or 1/4 mile? I wonder if those ~100ms save between shifts can benefit the times.
bTW, what oil do you use after you got the tunes?

For science I can try with XHP Stage 3 and without XHP. I really personally do not feel a butt dyno difference with XHP at all. But I really never dragy measured it.

Oil I use is Liqui Moly 0W20 Top Tec 6600. In the summer every 5K miles. And in the winter every 7K miles.

[vrships]

Originally Posted by suby01

For science I can try with XHP Stage 3 and without XHP. I really personally do not feel a butt dyno difference with XHP at all. But I really never dragy measured it.

Oil I use is Liqui Moly 0W20 Top Tec 6600. In the summer every 5K miles. And in the winter every 7K miles

So it's holding up just fine with 0W20? I was gonna get Top Tec 6600 but I thought it have better protection with 0w30 ( liquimoly B FE) since I now stress the engine harder than stock?

[suby01]

Originally Posted by vrships

So it's holding up just fine with 0W20? I was gonna get Top Tec 6600 but I thought it have better protection with 0w30 ( liquimoly B FE) since I now stress the engine harder than stock?

Quarter mile at a time. 😁

[Leem40i]

Originally Posted by vrships

I am not sure why this is not discussed widely before. I may have seen some posts mentioning in the m340 forum, but only slightly related

TLDR:

For those that have Bootmod3 and stage 2 or higher engine tune, you may really need the XHP to lift the torque limit to fully harvest the additional power. If you don't, the torque is gonna be limited <550nm all the way (under LC, it's even <500nm), while stg2 torque can easily go beyond 620nm.

=============================
Before XHP, I had been running stage 2 93 on a 2020 model for a few weeks. One thing I noticed is that the boost target and boost, when doing a 3rd gear WOT pull, was only around 16-17 psi at < 6000 rpm. This is as low as the stock boost, and much lower than the ACN91 boost (which is all the way >20 and boost target is 22.4). I was confused why stg 2 93 was so much more conservative than stg 1 ACN 91. It made no sense to me.

Although with stg 2 93 the car certainly runs faster, but the displayed "torque actual / target after clutch" is merely <550nm, while the torque predrivedynamics is 670nm. This is abnormal since with stock tune or ACN91 stg 1, these 3 torque values are within 30 nm different. Also these estimated torque values should be relatively accurate when compared between maps, meaning a 20% gain in these values should reflect on a real dyno run.

The facts are implying that the engine held up power somehow while it could do much better. I have asked ptf but they didn't find anything wrong, or explain the reasons why torque is [...]

Without a proper log to see what all your levels are during a run all of this is just shooting in the dark. Final horsepower and torque numbers do not dictate whether the car is performing properly or not.

[AshtonPJT]

I used 5w-40 and honestly it burns less oil and the engine sounds better. I’d look at EU approved weights.

[vrships]

Originally Posted by Leem40i

Without a proper log to see what all your levels are during a run all of this is just shooting in the dark. Final horsepower and torque numbers do not dictate whether the car is performing properly or not.

Why do you say so? I posted the pre/post logs you can clearly tell the differences.

That's almost 6 psi boost gain for low to mid range rpm, and 100 Nm torque too. Which amounts to at least 0.4s 0-100 time repeated many times.

[Rottweiler]

Well done vrships

Good thread and good supporting data

[vrships]

Originally Posted by AshtonPJT

I used 5w-40 and honestly it burns less oil and the engine sounds better. I’d look at EU approved weights.

I hate that clicking noise from the vanos and valves from the engine since day 1. Sounds cheap and broken.
But how does 5W40 ruin your highway MPG😂?

[AshtonPJT]

Originally Posted by vrships

I hate that clicking noise from the vanos and valves from the engine since day 1. Sounds cheap and broken.
But how does 5W40 ruin your highway MPG😂?

My foot ruins my mpg more than oil does😂😂

[apwm340i]

So what is the order of this. Do you flash BM3 first then xhp afterwards?

Or xhp first then BM3 after?

[AshtonPJT]

Originally Posted by AshtonPJT

My foot ruins my mpg more than oil does😂😂

-

[AshtonPJT]

Originally Posted by apwm340i

So what is the order of this. Do you flash BM3 first then xhp afterwards?

Or xhp first then BM3 after?

Doesn’t matter the order, I’d do both at the same time, make sure to cycle ign or it will fail the second flash

[Leem40i]

Originally Posted by vrships

Why do you say so? I posted the pre/post logs you can clearly tell the differences.

That's almost 6 psi boost gain for low to mid range rpm, and 100 Nm torque too. Which amounts to at least 0.4s 0-100 time repeated many times.

I didn't see any log here. Without knowing how your AFR, Timing and most importantly whether you're getting any knock retard is more important than just turning up boost.

[Rottweiler]

Originally Posted by Leem40i

I didn't see any log here. Without knowing how your AFR, Timing and most importantly whether you're getting any knock retard is more important than just turning up boost.

Back when I was working, we’d tell guys to look with their eyes and not their mouth

https://www.bootmod3.net/log?id=65dd...bc901ce26e3fe6

[suby01]

This was before XHP existed on the M40i. I can show you the time stamp of the datalog. So no XHP installed at all here...