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"In general, the S85 is an overall reliable engine if used wisely and regularly serviced as indicated by the manufacturer bean counters. Some frequent problems with the VANOS were signaled by clients. The connecting rod bearings are subject to premature wear-out and need replacement every 80,000 kilometers on average.

Like 15,000 mile oil intervals?
 

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Yeah, this was my favorite part

Otherwise not too bad.


Sent from my Moto Z (2) using Tapatalk
In a sense this statement is correct.
Exhaust scavenging and intake charge inertia At high rpm combine to give close to 20% higher cylinder filling than actual displacement.
Achieving 120% volumetric efficiency is the same as running 3psi of boost on a super charger
 

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And saying it was derived from the P84/5 is such a stretch it's fictitious. The S85 was inspired by, and was a celebration of BMW's F1 efforts but to say any piece of the architecture beyond # of cylinders and bank angle is shared with a formula racing motor would be fabrication. Furthermore, I know I've read in factory documentation that the V10 was only selected because engineers decided on creating a high-output 5 liter motor for this celebration of motorsport, and with the optimum displacement for a cylinder being .5 liters the V10 architecture was elected. A bit too fanboy'ish and furthering of misconceptions people often have about this motor.
 

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I count at least 4-pcs of F1 architecture in the s85, the main one being the bed plate of the E41/4

 

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More like 4 concepts. No different than saying V10, 90 deg, split-crankcase oh must be F1 - not really.

Split bedplate has been around (at least) since the 80's fyi...
 

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Volumetric efficiencies greater than 100% doesn’t mean supercharging per se, there are a few naturally aspirated production engines that have greater than 100% VE. Supercharging refers to a means of delivering air to the engine at pressures above atmospheric using artificial external means.
 

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Just because certain concepts were shared, cooling circuits (and I assure you the BMW_SAUBER had vastly more than two cooling circuits like the s85, modern F1 cooling is fascinating, far beyond complicated and worth research), cylinder count, use of bed plate (so does the N54, yet people don’t call it an F1 engine) or bank angle is a distant cry from being right when you telling everyone at the bar your German taxi has an F1 motor in it. Furthermore, Formula 1 is the business of everyone copying everyone else’s great ideas and coming up with a few unique ones of their own. These concepts have been around and BMW may or may not have came up with some of them, but because BMW leveraged it in an all out 18k screamer and a road-going screamer, says nothing more than the the concepts were good for both a race engine and high performance road car engine. They have different goals, measures of success, efficiencies and lifespan.
In no way is the s85 a race on Sunday buy on Monday engine - that level of carryover ended pretty soon after we started optimizing cars to race and simply never happened in the pinnacle of Motorsport where motors in this era only had to hold out for a single qualy session or a couple thousand race/practice kilometers.
 

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I just want to say, that if you want to compare engines that are F1 inspired, they must first have 10 cylinders! Then we can talk !!!


Oh yeah, one other thang, naturally aspirated !!!
 
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nice find. I wish FIA didn't meddle with max fuel injection pressure throughout the years. There's a chance that some form of direct inject would have propagated through the system at some point. I'd gladly deal with carbon soot on the valves in exchange for the massive power and torque bumps.
Direct Injection, the reason my Wife’s 2018 Mustang GT PP1 10-sp Auto is faster on the back roads. M5 6-speed faster on Track.

If I could compare torque curves, the Mustang 420 ftlbs of torque comes in much earlier than the m5 383 ftlbs and yet almost stays flat to 7,500 rpm redline, thus having substantially more area under torque curve than m5.

To me 420 lbft of torque out 5.0 liters is quite an achievement
 

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Came across this while reading some M5 literature, they at least were cast at the same plant (F1 engine and S85). Doesn't really matter other than neat history if you like such (I do).
1610594304384.png
 

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You all are taking very large hits on very large bongs if you believe S85 is an 'F1' engine.
Yes it has 10 cylinders, yes it has ITB's, yes it burns gasoline, yes the castings were probably done at the same place (probably really Becker), yes the cranks were made at the same place (Alfing).
Thaaaat's about it.
Otherwise, it's a road car engine. F1 engines are constructed a bit differently and do use different technologies in the various engine subsystems.
 

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You all are taking very large hits on very large bongs if you believe S85 is an 'F1' engine.
Yes it has 10 cylinders, yes it has ITB's, yes it burns gasoline, yes the castings were probably done at the same place (probably really Becker), yes the cranks were made at the same place (Alfing).
Thaaaat's about it.
Otherwise, it's a road car engine. F1 engines are constructed a bit differently and do use different technologies in the various engine subsystems.
But, but, but...

J/K
 
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