[zorgzx]

Hi. New I8 owner here, love it. Came straight from a 991 Carrera Daily driver and find it much better at pretty much everything. Ask me if you want to know comparison.

Anyway this might sound obvious, and I have done a few hours of searching, but cannot find:

Actual information on how the car is made in detail. I'm a nerd so I like to know the details. I have ofcourse read all the BMW blurb, and all the reviews but: They all seem to quote the same on the surface drivel. Theres surprising little Actual information.

A few examples of what I'm looking for:

How is the chassis made? Seed video of the build of panels being glued together, but is it hand lain, computer designed CF or how did they figure it / what is the design decisions behind the Alloy frame and CF cell ?

The petrol engine is related to the Mini engine, and reported as a twinpower unit. Is that twin scroll turbo or twin turbo? Is the turbo bigger than the Mini's ? The outbut is ceartainly higher.
Is it intercooled?
Does it have special components to handle the constant on/off states or just a wearble item?
How much is a new triple whan I kill it ?

How does the Electric engine and petrol work together, how are they synced, what would tuning the Petrol engine do to that sync?

How does the charging system work, why a battery in the front, is the EV battery 48v and the 12v batt for 12v systems?

As you can see these are all very technical. anyone know where to find some answers ?

[fishpond]

Originally Posted by zorgzx

As you can see these are all very technical. anyone know where to find some answers ?

Welcome and congrats on your new i8!

If you purchased your car from new, you will be enrolled in the Pure Impulse program - link below. The best event to attend to have all your questions answered is the Birthplace (factory tour) event where you have direct access to the designers and engineers.

Definitely well worth doing in my opinion.

https://www.bmw-i-pure-impulse.com/events/

[Jo-Sta07]

There is an actual "how it's made" episode from the science channel on the i8. If you look it up I'm sure you can find it. Perhaps YouTube.

[NGR]

Try the powertrain manual here...

http://www.rotory.com/bmw/I8.pdf

Very enlightening.

The turbo is a single unit, twin scroll I think.
The CFRP is some kind of molding process which reduces cost considerably compared to hand laid CF but keeps the strength and weight properties. It is still too expensive for future models though, BMW have said they will not be using it in future models - your car is one of the very few that has a full CF tub.

[zorgzx]

Originally Posted by NGR

Try the powertrain manual here...

http://www.rotory.com/bmw/I8.pdf

Very enlightening.

The turbo is a single unit, twin scroll I think.
The CFRP is some kind of molding process which reduces cost considerably compared to hand laid CF but keeps the strength and weight properties. It is still too expensive for future models though, BMW have said they will not be using it in future models - your car is one of the very few that has a full CF tub.

Highly enlightning, some nice innovative features there. Love the insulated engine, enabling no noise reduction in chassis.
The integrated turbo housing in manifold.
And the 2 seperate cooling ciurcuits for high and low temperature components.

Must read it in detail

Thanks.

[zorgzx]

Originally Posted by Jo-Sta07

There is an actual "how it's made" episode from the science channel on the i8. If you look it up I'm sure you can find it. Perhaps YouTube.

Thanks just watching it brings more clarity. I'm stumped that BMW built their own E engine. Hope to finde some info in the engine document as to why tesla can go without 2 stage transmission and BMW cant.

[zorgzx]

Originally Posted by fishpond

Welcome and congrats on your new i8!

If you purchased your car from new, you will be enrolled in the Pure Impulse program - link below. The best event to attend to have all your questions answered is the Birthplace (factory tour) event where you have direct access to the designers and engineers.

Definitely well worth doing in my opinion.

https://www.bmw-i-pure-impulse.com/events/

Thanks will look into a factory tour.

Funny side note. I love that the options on my (and I guess everyones i8) says large fuel tank option. Yet its only ever described as 42 litres. Wich is not very much

[Louv]

Originally Posted by zorgzx

...
Funny side note. I love that the options on my (and I guess everyones i8) says large fuel tank option. Yet its only ever described as 42 litres. Wich is not very much

It's been a few years since I knew this... but if I recall correctly, the US only gets the "large" tank, but other countries have an option for a smaller tank.

[MichaelJohn]

I wonder why BMW doesn’t publish the higher power numbers quoted in the powertrain manual? (368HP vs 357 and 457 lb-ft vs 420) I believe the starter/generator motor accounts for the difference but maybe it’s treated like an overboost and they can’t count it? That 457 torque number is pretty darn good especially considering the car’s weight. No wonder it has that nice kick when you step on it.

[zorgzx]

Originally Posted by zorgzx

Highly enlightning, some nice innovative features there. Love the insulated engine, enabling no noise reduction in chassis.
The integrated turbo housing in manifold.
And the 2 seperate cooling ciurcuits for high and low temperature components.

Must read it in detail

Thanks.

After reding a bit of it, I'm still no wiser as to WHY the engine is so much more powerfull than it is in the mini.
Does anyone have the figures on the mini engine, in the power manual its listed with a nice graph, nearly doubling the power, but little explanation as to how.
Boost is 1,5 bars, is mini only 0,7 ?

[Sophisto]

The B38K15T0 engine of the i8 is the only variation of B38 with the "T" in its code. The "T" describes the power level "Top" which is the highest internal BMW level as "S" ("Super") is reserved for the M models.

I. e. I know about a much higher fuel pressure at the injection valves.

You will probably never find out all the secrets behind the "T" as BMW has an strong interest to keep their business secrets.
(Things might look different if you have the option to compare engines/settings/parameters of mini and i8 in detail by yourself. )

[zorgzx]

Originally Posted by Sophisto

The B38K15T0 engine of the i8 is the only variation of B38 with the "T" in its code. The "T" describes the power level "Top" which is the highest internal BMW level as "S" ("Super") is reserved for the M models.

I. e. I know about a much higher fuel pressure at the injection valves.

You will probably never find out all the secrets behind the "T" as BMW has an strong interest to keep their business secrets.
(Things might look different if you have the option to compare engines/settings/parameters of mini and i8 in detail by yourself. )

This is the internet for f.ks sake, some one nerdy must know the innards of the mini engine. Even chipped variants does not push out the same amount of power.. will keep reading and post back.

[NGR]

Originally Posted by zorgzx

This is the internet for f.ks sake, some one nerdy must know the innards of the mini engine. Even chipped variants does not push out the same amount of power.. will keep reading and post back.

As the engine doesn't rev very high, the only way to increase power output is more fuel/air mixture per bang. Higher boost pressure would help of course, but as you point out, that doesn't bring normal Mini engines to the same level.

Maybe the turbo is very special compared to the Mini's? I suspect BMW went back to basics and flowed the head. That would make a difference on a highly charged engine but probably too expensive for large production runs e.g. on a Mini.

[JasH]

Turbo is much bigger & much more laggy I understand, which is not a problem on the i8 because BMW added the small electric motor to provide torque fill.

[zorgzx]

Originally Posted by JasH

Turbo is much bigger & much more laggy I understand, which is not a problem on the i8 because BMW added the small electric motor to provide torque fill.

Has anyone got any actual info on how this works?

Is it the starter/charger that does the filling, and is it allso that one that does the charging when in comfort mode?

I think I read somwhere in the I12 Drivetrain manual that it supports up to 50NM.

[Jason B]

Originally Posted by zorgzx

After reding a bit of it, I'm still no wiser as to WHY the engine is so much more powerfull than it is in the mini.
Does anyone have the figures on the mini engine, in the power manual its listed with a nice graph, nearly doubling the power, but little explanation as to how.
Boost is 1,5 bars, is mini only 0,7 ?

It's boosted to 25 psi! Which is unheard of usually from an OEM manufacturer, and usually only done that high with the aftermarket.

Originally Posted by Jo-Sta07

There is an actual "how it's made" episode from the science channel on the i8. If you look it up I'm sure you can find it. Perhaps YouTube.

Someone find this!

[JasH]

He really needs to do the Leipzig factory visit. All these questions would be easily answered by the i8 engineers there.

[zorgzx]

Originally Posted by JasH

He really needs to do the Leipzig factory visit. All these questions would be easily answered by the i8 engineers there.

Yes I really must look into this. Is that something that can be booked randomly or do I need to go on the wine and dine arrangements? I'm allways busy .

[zorgzx]

Originally Posted by Jason B

It's boosted to 25 psi! Which is unheard of usually from an OEM manufacturer, and usually only done that high with the aftermarket.

I trawled the Mini tuner scene and found they generally take the mini to 13psi. So I guess the main route to power is boost and efficiency of the charger, accept of cal, that is filled by the Charger/boost emotor on the engine. Or the front motor.. havent found info on that yet.

Someone find this!

Found it and saw it twice, it has lots of lovely info and insights but i want to know it all.

offtopic, I today found a fun game. Drive the car to work on allmost empty tank using sport the last part of the drive (late). Even with empty tank, but full battery the 12km drive home was fun, driving as fast as the E drive will go, wich is not too shabby on twisty roads Love the "lightness is rightness".

[JasH]

Originally Posted by zorgzx

Yes I really must look into this. Is that something that can be booked randomly or do I need to go on the wine and dine arrangements? I'm allways busy .

Randomly perhaps, but that will be the "lite" tour the dealers get.

The full and detailed tour with access to their engineers is via Pure Impulse only. Includes the "wine & dine", which is excellent.

I went in 2017 and am going again this Autumn. It's that good.

[zorgzx]

Originally Posted by NGR

Try the powertrain manual here...

http://www.rotory.com/bmw/I8.pdf

Very enlightening.

The turbo is a single unit, twin scroll I think.
The CFRP is some kind of molding process which reduces cost considerably compared to hand laid CF but keeps the strength and weight properties. It is still too expensive for future models though, BMW have said they will not be using it in future models - your car is one of the very few that has a full CF tub.

Finally found time to read it all.

A few interesting facts rarely mentioned:
1: Both the generator and electric engine does the boost and charge, and braking, each working their own axle optimally according to DME demands.

Generator i 50nm, Emotor is 250nm.

2: Emotor gearbox is in 1 gear during emode only, and 2nd in all other modes to be more efficient at 2 different tasks.

3: The battery state and combustion engine strategy is biased by the destination on sat-nav and the route thru urban areas and topography.
Very cool for 2014 tech.