M3-M4 Article from Engine Technology International, January 2014

[JoeFromPA]

The redline being 7800 rpms and the statements of torque increase over s65 at 2000 and 7500 rpms are new and specific interesting tidbits for me...

[basscadet]

Originally Posted by Kuwen

I thought it has been previously stated the turbos were Mitsubishi?

Indeed - that is what Car & Driver reported.

There's nothing wrong with Mitsubishi turbos but I think it is interesting that these are developed with Honeywell to be more solution-specific.

[ixse]

Originally Posted by Kuwen

I thought it has been previously stated the turbos were Mitsubishi?

thats a good thing.. i used to abuse the shit out of my evo.. sold it at 70k miles. never had a single problem. even on summer day at willow springs full day time attacks..

[Boss330]

Originally Posted by jsublime

Whether it's 84 or 89, both of these statements contradict earlier info about the engine being oversquare.

I know

http://f80.bimmerpost.com/forums/sho...d.php?t=893611

[Boss330]

I just did a rough measurement based on the original of the picture attached.

The bore is definitely larger than the stroke if we can go by the picture, but I haven't done a precise enough measurement to get a reliable ratio between bore/stroke.

[basscadet]

Why do we have all of this detail about the bore and stroke of the engine but we still don't have any performance figures for the car yet.

[JoeFromPA]

Originally Posted by basscadet

Why do we have all of this detail about the bore and stroke of the engine but we still don't have any performance figures for the car yet.

You mean the car that won't be reviewed by journalists for another ~6 months?

[solstice]

Autoweek states the exact same bore x stroke as the 1M and the piece in this post. The 80 mm bore above is obviously a typo and should be 84.

http://www.autoweek.com/article/2013...NEWS/130929883

That article also talks about a more than 200 lbs lighter CSL being considered with lightweight seats etc. I think Scott26 has hinted at this as well.

[mkoesel]

@solstice

Good article, hadn't seen that one mentioned before. Unfortunately there is so much conflicting information that we won't be able to call any of it fact until BMW makes it official.

[CanAutM3]

Originally Posted by Gearhead999s

I read somewhere that they are keeping the throttles open under deceleration to reduce pumping losses to help keep the turbos spooled up but only when its in the sport or sport plus drive modes.I cannot remember where I read this though

The S55 does not have throttles...

...keeping intake valves open?

[solstice]

Originally Posted by mkoesel

@solstice

Good article, hadn't seen that one mentioned before. Unfortunately there is so much conflicting information that we won't be able to call any of it fact until BMW makes it official.

I agree that as a community or fact source we need the official fact sheets to call it but two sources stating Biermann with the standard BMW I6 numbers and references to the 1M with that the S55 share only bore x stroke plus a few others is enough for me personally, i.e I believe the S55 has the same bore stroke as the standard I6s of 84 x 89.6

[Boss330]

Originally Posted by CanAutM3

The S55 does not have throttles...

...keeping intake valves open?

Or rather keeping BOTH intake and exhaust valves open perhaps

I know the valvetronic operates the intake valve instead of a throttle, but obviously you need exhaust valves open as well to get flow

[Gearhead999s]

Originally Posted by CanAutM3

The S55 does not have throttles...

...keeping intake valves open?

I should have said being throttled

[Boss330]

Originally Posted by solstice

Autoweek states the exact same bore x stroke as the 1M and the piece in this post. The 80 mm bore above is obviously a typo and should be 84.

http://www.autoweek.com/article/2013...NEWS/130929883

That article also talks about a more than 200 lbs lighter CSL being considered with lightweight seats etc. I think Scott26 has hinted at this as well.

Yes, there is a lot of confusion so far, but the quoted 80mm and 89,6mm measurements have been reported by Auto Motor und Sport as well as CAR, along with a description of the engine being oversquare, so they have obviously not just made a simple typo.

http://f80.bimmerpost.com/forums/sho...d.php?t=893611

The Engine Tech International article also mentions 80/89,6mm but has got it backwards and has the 80mm stated as the bore. That equates to a volume of 2,7l, so definitely not correct.

It either has a 80mm stroke and 89,6mm bore or a 89,6mm stroke and 84mm bore. From the photo I posted the bore is definitely larger than the stroke, but hard to verify as being correct due to angle of the engine on the photo etc.

[Kadema]

40% more torque at 7500rpm would be 530~555hp, at least much more than 430 - I highly doubt that.

Also, at 2000rpm it seems to be much more than 70% more torque. More like 230%.

[solstice]

Originally Posted by Boss330

Yes, there is a lot of confusion so far, but the quoted 80mm and 89,6mm measurements have been reported by Auto Motor und Sport as well as CAR, along with a description of the engine being oversquare, so they have obviously not just made a simple typo.

http://f80.bimmerpost.com/forums/sho...d.php?t=893611

The Engine Tech International article also mentions 80/89,6mm but has got it backwards and has the 80mm stated as the bore. That equates to a volume of 2,7l, so definitely not correct.

It either has a 80mm stroke and 89,6mm bore or a 89,6mm stroke and 84mm bore. From the photo I posted the bore is definitely larger than the stroke, but hard to verify as being correct due to angle of the engine on the photo etc.

Good point about the possible reversal of bore and stroke in this article. It seems a bit strange though that Biermann doesn't use this to argue the difference to the 1M engine. It would put an end to any speculation of reuse and similarities. It could of course be that Autoweek is the only source here and that they have manufactured facts and quotes or just gotten them wrong which would surprise no one.

[Boss330]

Originally Posted by solstice

Good point about the possible reversal of bore and stroke in this article. It seems a bit strange though that Biermann doesn't use this to argue the difference to the 1M engine. It would put an end to any speculation of reuse and similarities. It could of course be that Autoweek is the only source here and that they have manufactured facts and quotes or just gotten them wrong which would surprise no one.

Yeah, we'll just have to wait for official specs.

[BMW M3 CRT]

For me its clear, that one statement in this forums engine spec must be wrong, if the S55 is based in the N55 than an bore of 89,6mm is impossible !!!

[Boss330]

Originally Posted by BMW M3 CRT

For me its clear, that one statement in this forums engine spec must be wrong, if the S55 is based in the N55 than an bore of 89,6mm is impossible !!!

If it shared the block, yes it would be impossible with the bore spacing of the N55.

It is a all new block and that is also visible from the photos. However if that means a new bore spacing and 89,6mm bore is a different matter. But according to Biermann the engine shares nothing apart from some ancilliaries with the N55, so who knows?

BTW did you find the info on 80% unique components on the E9x M3 that we discussed on the other thread?

[solstice]

Edmunds has the same numbers and possible mistake. From reading a few of the articles from different sources I wonder if there are only two conflicting sources that has been copied by the others. Here's Edmunds piece that matches this post:

"Weighing 452 pounds fully dressed, the engine is 22 pounds lighter than the V8 it replaces, even with its pair of Honeywell turbochargers and indirect intercooling system attached. The two turbos generate around 18 pounds of boost pressure, which is then fed through the intercooler into chambers with an 80mm bore and an 89.6mm stroke."

http://www.edmunds.com/car-news/2014...-revealed.html

[Boss330]

Originally Posted by BMW M3 CRT

Really interesting fact ... seem like the inside source from the german m-forum was right as he tells me, that the new S55 (205kg!) would be a little bit heavier than the ongoing S65 (202kg!).

Seem logical ... if you compare the engine netto weights, an 3.0ltr.I6 is probably lighter than an 4.0ltr.V8, but in gross weight an BiTurbo with racetrack proof cooling need many heavy cooling parts ánd its never less an great weight saving effort to make him in nearly the same weight class als an proven lightweight V8.

Greetings BMW M3 CRT

This article also mentions the 10kg weight save and quotes a weight of 195kg (which actually adds up with the claim of 10kg lighter than the S65)

Here Biermann is quoted as saying that the S55 shares bore and stroke with the 1M engine... Meaning a 84mm bore and 89,6mm stroke... We will have to wait and see...

http://skiddmark.com/2013/09/bmw-rev...-m3-m4-wvideo/

[catpat8000]

Originally Posted by solstice

Edmunds has the same numbers and possible mistake. From reading a few of the articles from different sources I wonder if there are only two conflicting sources that has been copied by the others. Here's Edmunds piece that matches this post:

"Weighing 452 pounds fully dressed, the engine is 22 pounds lighter than the V8 it replaces, even with its pair of Honeywell turbochargers and indirect intercooling system attached. The two turbos generate around 18 pounds of boost pressure, which is then fed through the intercooler into chambers with an 80mm bore and an 89.6mm stroke."

http://www.edmunds.com/car-news/2014...-revealed.html

Remember the internet is a giant echo-chamber so all these numbers (and mistakes) probably originate from the same place - BMW.