Best FCP option for BMW N55 (2016 M235i)?

[BMWTurboDzl]

Turbo spool is dictated by the wheel size I choose, the turbo design (I use mostly twin scroll now) and my timing and boost ramp calibration.

You will not see anyone find telemetry data that identifies difference in spool on these oils discussed. And we are talking about 100 samples per second of telemetry data not being able to see it.

I'd sincerely be interested if you have any though. I've simply never seen anything like you are describing so I'm open to your data

I asked about fuel flow. Are you saying that there's no difference in the amount of fuel delivered to reach a specific rpm within the same amount of time regardless of HTHS? This would be news to the automakers worldwide.

From Lubrizol

LINK


"Long haul heavy duty commercial vehicles can realistically expect fuel savings of 0.5-1.5% by switching from SAE 15W-40 to 5W-30 HTHS engine lubricant. Further savings when switching to low HTHS viscosity engine lubricant can be expected to add 0.4-0.7% of increased fuel efficiency, depending on the engine type and operating conditions.".

Total FE savings from a 40w with HTHS of 3.5 or higher to a 30w sub-3.5 hths could be anywhere from .9% - 2.2%.

 

[BMWTurboDzl]

I've gone from *w20's in a few engines to *w40's and never noticed the slightest difference.

Perhaps it's because you're not a neurotic owner of an out of warranty BMW? ROFL.

 

[Bailes1992]

I asked about fuel flow. Are you saying that there's no difference in the amount of fuel delivered to reach a specific rpm regardless of HTHS? This would be news to the automakers worldwide.

I think what people are getting at is the difference would be just a small percentage point that you wouldn't be able to detect it without specialist equipment.

My old 2020 BMW 520d MHT Touring had an 48v 11hp electric motor which could 'assist' the 190bhp engine in certain circumstances if there was power in the battery. Flooring it with the 11hp motor assisting or not I could never tell the difference despite it being an additional 6% of the combustion engines power.

Perhaps it's because you're not a neurotic owner of an out of warranty BMW? ROFL.

See above!

I've also just taken on a new job which I start Monday involving a lot more long distance driving. Trying to convince my Wife to let me chop in my 8 month old Dacia Duster for a 5 year old 330d or 335d. It's not going well.

 

[bhvrdr]

To be accurate it's unknown rather than almost.

Here's a tidbit from Lubrizol

LINK


"Long haul heavy duty commercial vehicles can realistically expect fuel savings of 0.5-1.5% by switching from SAE 15W-40 to 5W-30 HTHS engine lubricant. Further savings when switching to low HTHS viscosity engine lubricant can be expected to add 0.4-0.7% of increased fuel efficiency, depending on the engine type and operating conditions.".

To summarize total fuel consumption savings from a 40w with HTHS of 3.5 or higher to a 30w sub-3.5 hths could be anywhere from .9% - 2.2%..

1. fuel economy differences and engine drag is vastly different from turbo spool. The lubrication differences between an ICE and a turbocharger bearing/ bearings are not comparable.

2. The OP is not talking about the difference between a 15w40 and 5w30 nor any sub 3.5 hths oils. So focusing the difference between a 3.5 to 3.8 hths oil let's look at what that could possibly mean.

3. So let's say there was a 0.5 percent difference in spool... which there likely isn't... Again we're way over estimating here because we're comparing ICE fuel economy differences and turbo spool up. Literally a fools errand but I'll be a fool....

...this would still literally be immeasurable on anything other than computer models (ie, not mechanically nor via logging) and definitely not perceivable to the human body. Youd have hundreds of times (literally) greater difference in spool just by changing load (like surface slope). We'd be talking a 10rpm difference in spool at 2000rpm. 10rpm. And the true number is likely only a percentage of that.

 

[BMWTurboDzl]

1. fuel economy differences and engine drag is vastly different from turbo spool. The lubrication differences between an ICE and a turbocharger bearing/ bearings are not comparable.

2. The OP is not talking about the difference between a 15w40 and 5w30 nor any sub 3.5 hths oils. So focusing the difference between a 3.5 to 3.8 hths oil let's look at what that could possibly mean.

3. So let's say there was a 0.5 percent difference in spool... which there likely isn't... Again we're way over estimating here because we're comparing ICE fuel economy differences and turbo spool up. Literally a fools errand but I'll be a fool....

...this would still literally be immeasurable on anything other than computer models (ie, not mechanically nor via logging) and definitely not perceivable to the human body. Youd have hundreds of times (literally) greater difference in spool just by changing load (like surface slope). We'd be talking a 10rpm difference in spool at 2000rpm. 10rpm. And the true number is likely only a percentage of that.

Okay I see the confusion. I said "turbo lag" when I should've said "throttle lag".

 

[kschachn]

The hole gets deeper and deeper.

 

[bhvrdr]

Okay I see the confusion. I said "turbo lag" when I should've said "throttle lag".

Throttle lag is an issue between the throttle pedal sensor, the ECU, and the mechanical tb and the tb solenoid.

Here's a video...



I tend to have had the best results addressing throttle lag with a combination of remapping and sometimes actually modifying the throttle body.

 

[BMWTurboDzl]

Throttle lag is an issue between the throttle pedal sensor, the ECU, and the mechanical tb and the tb solenoid.

Here's a video...



I tend to have had the best results addressing throttle lag with a combination of remapping and sometimes actually modifying the throttle body.

Ya I'm aware that type of lag but that's not what I'm talking about.

 

[BMWTurboDzl]

The hole gets deeper and deeper.

Hardly. You guys so easily discount factual impacts HTHS has on fuel economy when there's a mountain of evidence staring right back at you. And yet you cling to my comment where I stated I noticed a difference in throttle response on a w40 of unknown HTHS compared to previous 30w oils (Some of which were sub 3.5). I can't help it if the throttle must travel a little bit further to deliver the expected result within the expected time frame.

Found this gem.

Link

"..This work presents the performance and efficiency of a needle bearing type turbocharger under low load condition as affected by lubrication oil temperature and viscosity. The turbocharger on a test bench was propelled by known component exhaust gases with controllable mass flow and temperature at the turbine side. Two API SN multi-grade lubrication oils 0W-20 and 10W-40 were tested. The lubricant flow rates were kept constant by external supply at different inlet temperatures. The turbocharger efficiencies were determined by the measured inlet and outlet temperatures, pressures and flow rates for both turbine and compressor sides as well as the shaft rotational speeds. The experimental results were revealed that the higher inlet temperatures related to the thinner lubricant resulted in higher turbocharger efficiency. It suggests that the lubricant thermal manipulation is required for turbocharger under low load condition to operate within the design performance window...'

 

[bhvrdr]

Ya I'm aware that type of lag but that's not what I'm talking about.

What throttle lag were you speaking of?

 

[BMWTurboDzl]

What throttle lag were you speaking of?

Differences in the degree of input (ex. peddle travel) when attempting a passing maneuver at highway speeds. I noticed on a couple of occasions where I had to add more throttle than expected. Not a big difference but it was different. This is the only area where I've noticed a difference between LL01FE 0w30 (Sub 3.5 hths) and LL01 5w40 (3.5 hths or greater).
I've noticed no difference in warm up. The needle on the oil temp gauge comes off bottom at the same distance as it always has. I can't comment on mpg because I only drive the car every couple of months and there are too many variables.

 

[TiGeo]

Blind "Pepsi Challenge" test time.