I'm not sure if anyone has really done a thread like this, so here goes.

I wanted to just put to pictures a very general overview of what's going on under the bonnet of the F56 in terms of component location and the general technology involved.

Step 1: Open the Bonnet. MINI is using a new style latch where you do a "double pull"; once to unlock it, and another pull to release it. No more fiddling around by feel to find that latch that's never where you left it.

IMG_7400.jpg by Ryephile, on Flickr
-->Note: I had just washed the car, hence the rusty rotors.


Here's what we get: an engine bay shot.
IMG_7404.jpg by Ryephile, on Flickr


On the underside of the bonnet, we have the stickers that show what legal standards the car abides by:
IMG_7399.jpg by Ryephile, on Flickr


If we give a firm tug to each of the 4 corners of the MINI branded engine cover, here's what the underside of that looks like. Thick acoustic foam quiets the sound of the direct injectors and high pressure fuel pump.
IMG_7403.jpg by Ryephile, on Flickr


Here's the exposed valve cover of the engine. Just to point some things out, starting at the middle top with the foam block with the two cables coming out of it, that's the high pressure fuel pump. Clockwise from there, the diagonal tube is the induction pipe going from the air filter to the turbo compressor inlet. Clockwise from there is the big fuzzy box with the red cap, that's the environmental box for the battery, power distribution, and engine control unit (ECU). Then we have the airbox itself, with fresh-air duct connected to the front bumper. We'll get to the rest shortly.
IMG_7394.jpg by Ryephile, on Flickr

Going further on this picture, there are four parallel lateral lines between the valve cover and the intake manifold. The upper one is the low pressure fuel feed line. The next one down is the wiring harness for the Valvetronic servo. The third one down is the evaporative emissions vent hose and solenoid coming from the fuel tank and charcoal canister, and the bottom line is the +12 volt positive cable from the battery to the alternator to the starter.


To be continued...

 

Zooming into the engine itself a bit. Center of the picture is of course the oil filler cap. Bottom center of the picture is the wiring connector for the Valvetronic servo. This is connected to a 3rd camshaft [yes really] that controls how much valve lift the intake valves achieve. This is controlled by the ECU's complicated algorithm to maintain minimum pumping losses across the valve head. The result is a typical MAP of 90kPa, unless turbo boost is being used. Also visible in the lower left of the picture are the two Air Conditioning refilling ports.
IMG_7396.jpg by Ryephile, on Flickr


Pushing in a little more from the last picture, we can see the coil-on-plug's, the fuel rail, fuel rail pressure sensor, and two of the piezo fuel injector wiring harness plugs. In the upper left are the two crankcase ventilation hoses.
IMG_7397.jpg by Ryephile, on Flickr


Ok, switching areas, to the air filter, or "intake muffler" as they're called now. Here is the stock paper filter. Paper is used by OEM's because it's affordable and does a fantastic job filtering small particles. Here, with 72 3-inch tall pleats and a 9.625" average width, this filter has an astounding 2,079 square inches of filter surface area. That's awesome! It will take a very free-flowing [and subsequently not very effective at actually filtering] for the aftermarket to get more filter area in the car.
IMG_7424.jpg by Ryephile, on Flickr


Here's the dirty-side of the airbox. More importantly, the clean-side of the airbox with its reservoir of clean air is important for transient response.
IMG_7423.jpg by Ryephile, on Flickr


Here's the clean-air side of the airbox, detailing the quasi-velocity stack right in front of the mass-air flow (MAF) sensor. This sensor has a direct correlation to how much power the engine is making, which then makes for very nice OBDII datalogging. The smooth radiused inlet reduces turbulence and makes good power.
IMG_7422.jpg by Ryephile, on Flickr

 

...and the final chapter for now...

Here are the two panels you have to remove to service a whole bunch of things. The brake reservoir and booster, the ECU, the battery, and power distribution.
IMG_7425.jpg by Ryephile, on Flickr


With those popped off, here's what it looks like underneath. The white box on the left houses the ECU.
IMG_7426.jpg by Ryephile, on Flickr


Here's a close-up of the battery. Indeed it says "AGM", which means Absorbed Glass Mat design. That would make it a non-spillable battery. 80 Amp-hours is a big capacity, likely to help with the Stop/Start engine operation.
IMG_7427.jpg by Ryephile, on Flickr


The wiper motor is situation above and aft of the battery. Also note the negative battery terminal's strange shape; it uses a pyrotechnic device to disconnect the battery in a collision, greatly reducing the chance of fire.
IMG_7430.jpg by Ryephile, on Flickr


Was this helpful? What topic or area would you like to see expanded on?

 

Great job Rye !
Very helpful and well stated.
Perhaps a few notes on how to remove those covers that you have
removed in the tutorial.
Simple maintenance would benefit many members, even if we don't intend to wrench,
it is beneficial to understand the operations.

 

Much better than the car, not car level understanding I have, thank you!

 

This is one of the best posts in here yet! I always try to pop the hood and point out some of the different components and subsystems to my wife, but haven't bothered to remove any covers to dig in deeper like you have.

thanks for the time you've put into this, and yes, more would be appreciated.
maybe pull a wheel and point out the different suspension components? arrows on the pictures might be nice for some.

 

Great information - thanks!

 

Thank you for this, very good info. Any idea where you'd be able to find your engine code... still trying to figure out if I have a b46 or 48. Thanks

 

Good Job, before i realized the double pull i once forced it open

 

Nice Job R,


All the site vendors just black listed you for exposing how good the oem paper filter/housing/velocity stake intake design is.(lost sales for "hot air intake kits")
Or, as their known in the industry as "cash flow devices". Minimal investment in materials with no research & development/dyno cost for the vendors -but yet huge profits (cash flow) with each sale.


I think the F56 JCW motor will most likely benefit from mods on the exhaust side(down tube/cats/header etc. The BMW engineers already made a nice airbox. Why **** away $400.00 for a loss in HP.

 

Just to add to this terrific post. Great job Ryan.
When you pull the battery there is a connection box with built in fuses. These range from 250amps and down to 60amp if I recall correctly. These are a great way to run a large amperage positive feed through the firewall to the right of the battery. The box is closed and pretty much water resistant.
Don't mean to hijack the tread....just to add to it.

 

Thanks for the additions GregoryK. Seeing the fuses inside the distribution box is handy. Your 2nd picture also shows one of the two shift cables on the transmission, which is good to see.


Per request from g34343greg, I added arrows and descriptions to some of my pictures. I intentionally labeled some of the same things in different pictures to retain perspective. Hope this helps!


engine1notes by Ryephile, on Flickr

engine2notes by Ryephile, on Flickr

engine3notes by Ryephile, on Flickr

engine6notes by Ryephile, on Flickr

Cheers,
Ryan

 

Very informative and helpful. Thanks for putting in the time!

Maybe make this a sticky we can reference to?

 

Thanks!

I just noticed an error in the 4th picture; I forgot the remove the "intake manifold" box and arrow; it's just pointing to sheetmetal. LOL oops.

 

Guys anyone know where I may find the engine code in the bay? Trying to find out if I have a 46 or 48, thanks.

 

Use the Vin decoder..bmw one.

 

Thanks, new to the forums and mini so Im not too aware of the resources. Thanks once more.

 

pyrotechnic what!!

(thanks for all this information folks!)

Cheers,

Charlie

 

Yea it really isn't that big of a deal. BMW has been using them in the MINI's since the beginning. You also hold one every time you drive the car [the steering wheel]. You also buckle into one every time [the seatbelt pre-tensioner].


And thanks, glad to help.

 

You guys ready to raise the bar? Ok, let's start by looking at some OBDII datalogging!

First step is to get yourself a nice little On Board Diagnostic-II interface and some PC software. I use simple but effective software called OBDwiz and an OBDLink SX scan tool cable, that connects from the SAE J1962 standard connector and pin-out to your PC's USB. On the MINI's, the OBDII connector is right above your feet in the footwell of the left side [driver for USA & EU, passenger for UK & Aus].

For the full scoop on OBD and its history, Wikipedia has a solid description.

Ok, so what comes out of this is the interface allows you to read all the sensors the OEM outputs onto that bus. Things like engine RPM, Manifold Absolute Pressure (MAP), Mass Air Flow (MAF), ignition timing, coolant temperature, intake air temperature, Oxygen sensor, and a whole host of other sensors, calculations, and outputs. The Scan-tool also allows you to read and clear OBDII "check engine" light codes, including observing the "freeze frame", which is a snapshot of what the engine was doing at the time the ECU posted the check engine light code.



Let's take a look at some basics. Here is a 13 minute cruise during my morning commute. Most of it is cruise control on the Interstate, in 6th gear at about 2,900 RPM. There are 4 attributes being shown here: MAF, MAP, Wideband Oxygen sensor, and cylinder #1 Ignition Timing.
datalog1 by Ryephile, on Flickr

Don't worry about looking at it too hard. If it looks like greek, that's ok, it's not terribly descriptive with so much data being shown over such a long period of time. If you look closely at around the "1400" mark [timestamp on the datalog], you can see that the MAP and MAF both spike. That was me tipping in to get some passing power. Looking at the exact CSV data cells, that ended up being about 110 HP at 2300 RPM with 10.5 PSI of boost, and an inferred G100 Air-Fuel Ratio of 14.1:1, or Lambda 0.96 actual. Making some assumptions about Brake Specific Fuel Consumption, that equates to about 251 Lb Ft of torque.



Ok, I lost you. Come back! This next graph is more interesting.

datalog2 by Ryephile, on Flickr

This one shows a different time region than the above one, and this time it's only 15 seconds long, in 4th then 5th gear, and me flooring it in the middle of the graph. This allows us to see more detail. This graph shows more sensors, MAF, MAP, Lambda, ignition timing, commanded torque request, and engine RPM. I fiddled with the scales on RPM and Lambda so they had more resolution. For Lambda, the middle of the graph correlates to Stoichiometric, or 14.7:1. Lower on the graph is richer, and the top of the graph is free-air during fuel cut.

You can see that from the left of the graph I was just cruising along. Then the commanded torque goes to 100, the boost rises, the air flow rate increases because the engine is making more power, and the ignition timing retards to minimize knock and get rational combustion for the given torque. This was in "Mid" mode, and at 3900 RPM the engine ended up making about 170 HP, or about 229 Lb Ft of torque. This was also downhill on an on-ramp, so the ECU calculated I didn't need as much torque based on that and my pedal rate of change being reasonably lazy. The torque calculation is very complicated, as we can see. The engine doesn't make a fixed boost level, but instead calculates how much torque you really want and adjusts the boost, throttle body, Valvetronic servo, intake and exhaust cam phasing based on all the sensor inputs.


Clear as mud? Oh one last thing for now. Once the engine is up to temperature, it appears to settle at about 224°F coolant temp and 215°F oil temp. This is totally normal for current cars.

 

Tons of great and interesting information! Thanks, Ryephile!

 

You're welcome!

Ok maybe I jumped the gun a bit. Let me step back and explain how our B38 and B48 engines work before going deeper with the datalogs. Here are the fundamental bullet points for the B38 3-cylinder in the Cooper, and the B46/B48 in the Cooper S and JCW:

*500cc per cylinder, giving shared piston, connecting rod, and valvetrain components across the family line-up.
*Cast Aluminum cylinder block, cylinder head, and oil pan. High-temp plastic valve cover [quieter than aluminum].
*three camshafts, one for intake, one for exhaust, and one for intake valve lift actuation [Valvetronic]. Phase adjusters on intake and exhaust camshaft [Double VANOS].
*4 valves per cylinder, two intake and two exhaust. Exhaust valves are sodium filled for improved thermal capacity during long-term stresses like going to the racetrack.
*Bosch MEVD 17.2.3 engine control unit using Infineon's Tri-Core microcontroller, with CAN, and Ethernet. A veritable supercomputer under your bonnet.
*Direct injection using current-gen piezo injectors, centrally located for very precise fuel injection into the piston "bowl", improving the stability of stratified combustion. High pressure fuel pump driven off exhaust cam extra lobe.
*fuel delivered from tank by a returnless single line system
*Single knock sensor mounted centrally between cylinders 2 and 3. Fast response Wideband Oxygen sensor [maybe LSU 4.9, TBD]. Very high density crank tooth wheel, tooth count TBD. MAF, MAP [in intake manifold], and T-MAP [upstream of throttle body] contribute to a highly developed efficiency optimized torque targeting algorithm instead of old school fixed maps.
*structural high-temp plastic intake manifold
*vacuum pump built into cylinder block for consistent brake booster operation during boosted engine operation.
*cast exhaust manifold & turbocharger turbine as one piece. Coolant cooled and oil lubricated CHRA. Electro-pneumatic wastegate operation, electronic diverter valve operation. 3-cylinder gets a single-scroll turbine, 4-cylinder gets twin-scroll turbine.
*twin counter-rotating balance shafts to damp engine resonances.
*two timing chains; one from crank to idler, and idler to both camshaft sprockets. This is routed around the front-side of the flywheel in order to create a more compact engine.
*two catalytic converters, one close-coupled for primary emissions scrub and a secondary for additional cleaning


What does this all mean? The engine doesn't simply use a throttle body anymore, that's just one part of the equation. Valvetronic uses intake valve lift to also "throttle" the engine. In this 4th gen Valvetronic, the ECU uses both the throttle body and the Valvetronic to target a specific minimum pumping loss across both the throttle body and the valve heads to maximize fuel economy, even at full load. When you tip-in the throttle part way, the ECU is figuring it out in real-time whether to use the throttle body, the Valvetronic, or a mix of both in order to give the perfect torque output with the maximum amount of thermal and volumetric efficiency.

The direct injection system has a few key difference compared to old school small block Chevy's, and even more recent port injection systems. The primary differences are the much improved chemical quench that results from a significantly finer mist of fuel, and the quicker combustion speed due to that finer mist and also the small diameter cylinder bore. All those factors contribute to ignition timing much less advanced than many hot rodders may be familiar with. No more are the days of slow-burn SBC's needing 45° of advance to get decent power. With the new MINI engine, it's looking like between 2 and 14 degrees of advance [BTDC] is all that's needed for correctly timed combustion at full load, and as retarded as -13° BTDC at very low load and RPM. Another benefit of the center-mounted DI system is the ability to run at Stoich, or closer to peak torque Lambda at high loads if desired. This is afforded again by the chemical quench of the fine mist, meaning cool EGT and low component stress. This allows for the boost to be turned up at lower RPM, where knock would otherwise make such high boost/low RPM operation impossible.


Ok, hopefully that helps explain some of the philosophy behind the engine operation in general.

 

Any idea where fresh air enters for the A/C when it is not set to recirculate?

 

To be honest I didn't take a picture of it. There'll be a duct somewhere in the cowl underneath the wipers for the HVAC fresh-air inlet, separate from the engine bay.

 

'Tis a Beautiful thread - underhood pics, OBD, and engine theory(?)

I have a few questions about the OBD in post #20 ...

What is the OBD command that equates to "commanded torque" ? I'm guessing it's one of these throttle commands ?
SAE.TP
SAE.APP_R
SAE.TP_R
SAE.TP_B
SAE.APP_D
SAE.APP_E
SAE.TAC_ACT

What value are you using for "Brake Specific Fuel Consumption" ? Is this for a plain MCS or a JCW version ? I have a '014 MCS.

-Mike