Why we all will miss "high-revving" engine

[Slapshot9]

Originally Posted by Mike Benvo

I'm not brave enough to try it, but if anyone is I will raise your redline for free!

Sounds like a party worth attending! As a bystander on my part. Who's in??

[PrimoM3]

Originally Posted by ///M Power-Belgium

A month ago i came back from work (pm-shift)
I stopped at the traffic light....and yes a GTR stopped alongside of me.
After two second's my MDM was already pressed !and i have DCT....and
gave full trottle...i assure you..the GTR flew away ( and yes i can drive my ///M.Got the impression that i was moving in almost slow motion !
It was a big disappointment for me...believe me !
But still ...i love my ///M3

Yeah, they're crazy fast and an engineering/technical marvel by all right, but they're disconnected and too technical (for me). As someone stated above, it's like an Xbox. And they look like shit. Yeah, I said it.

[Eau Rouge]

Originally Posted by Munit

For me the reasons were straight forward.
1. Probably the most important to me is the sound of the engine and car that you cannot get in any other setup. I really enjoy sound every single drive in this car.
2.the "special" feeling of being somewhat "near" race-car like feel. Nascar actually does not rev much higher than ours. Obviously F1 does but nonetheless it gives you a bit of that "race-car" like feel which makes it feel special each time you drive, atleast for me.

But in the end, while I will miss it, I guess I can't say the important things besides throttle response which seems to be getting better with each engine, will really be negatively effected. Curious other poeples reasons for liking the high-revving nature?

The S65 is the last and best interpretation of ///M engine building philosophy. The "S" might as well stand for "soul" as the S65, like the S54 before it, have such character (See your #1 point).

Of course successive generations of M3/4 will follow in the footsteps of their generational predecessors by delivering more performance, but if more performance had been the overriding goal, Nissan had/has just the car for me.
The S engines are special not only for what they do, but how they do it.

Originally Posted by Mike Benvo

I will never, ever, ever sell this M3. I might get the new one when it comes out (just because I like to have every new BMW!), but this M3 and my 7 series will never leave my fleet.

Something about a tightly knit small block V8 at 8,700 RPM really makes me smile.

+1 It's an unqualified keeper.

[Mike van D]

I'm sure the next gen will be a beast, wouldnt expect anything less from the ///M Division. For those of us who grew up with muscle cars back in the 70s, the S65 brings all that NA small block V8 fun around again.

[Superfly_M3]

Originally Posted by Mike Benvo

I'm not brave enough to try it, but if anyone is I will raise your redline for free!

I think the valve springs won't keep up and you might outrun the flame (someone should calculated the piston speed at 10,000rpm).

Whether you like it or not, the powercurve and displacement of the S65 is very similar to B18C5. Dating back to the Honda days, I've seen 9,500rpm with a heavily built NA motor that included everything. 10K is like Warp 10 ... Its something hard to get on a Valve Spring motor, especially 4.0L

If someone would like to try, I would like to see this.

Getting back on topic, the S65 will hold a very special place in my heart for the sole reason of the sound alone. This motor is by far the best sounding I have ever heard.

I can only imagine what power and noise those SCed guys are feeling.

[bruce.augenstein@comcast.]

Originally Posted by MKE_M3

There are engineering advantages (and some disadvantages, of course) to generating horse power at high RPMs, vs. low RPMs.

Consider two engines, both putting out 414HP, one puts it out at 8000RPM, the other at 4000RPM (think big turbo diesel). The first only makes around 250 lb-ft of torque, while the second makes around 546 lb-ft of torque. The drive train strength for the car making 250 ft-lbs is much lower than the needs of the engine producing 546 ft-lbs. This means that the high revving engine can be partnered with a lighter drive train.

There are some difficulties with this explanation. First, let me change the pairing. Let's use the current Corvette ZR1 engine paired against the four liter M3 engine.

The ZR1 makes 604(!) pound feet of torque, or a little more than double the M3 figure. That means the ZR1 clutch needs to be a bunch beefier than the M3 unit, and it also means the transmission input shaft needs to be very beefy, and/or made out of unobtanium, and/or heat treated to within an inch of its life.

However, consider that the first gear ratio of the ZR1 is at 2.29, vs the M3 ratio of 4.06. First, the torque capacity of a given transmission varies depending upon its first gear ratio - meaning that multiplication of torque is trying to tear the rest of the transmission apart. One of the ways you increase the torque capacity of a transmission is to numerically lower the gear ratios, and the Vette is a prime example of this. The Grand Sport's transmission is rated at around 480 pound feet of torque with its 2.95 first gear, but the ZR1 box (same case, gear sizes, etc.) is rated to take 600 foot pounds, in large measure because of its 2.29 first gear ratio.

Yes, there are other changes, but the ratio change is the biggest enabler. The Vette trans weighs around 220 pounds, while if memory serves, the M3 box comes in a a hair over 200, largely because it needs to be beefy to enable that aggressive first gear ratio.

Now, let's compare torque at the transmission output. In the Vette, it's a massive 1383 pound feet, but wait!, the M3 shows a not inconsequential 1198 pound feet (295 X 4.06), meaning the Vette is only showing about 15% more thrust at that junction. 15% means that the differential and half-shasts need to be beefed up, but not by a ton.

My overall point on this is that big torque requires less aggressive gearing, so driveline weights don't change very much. Consider the ZR1, with more than double the M's torque, only needs 15% beefier components, except for the transmission input.

Originally Posted by MKE_M3

Additionally, less torque requires(generally) less displacement (or lack of hardware like super/turbo charger), which also saves weight.

Lighter is better for sports cars.

In general, I agree, but consider that the Corvette Grand Sport engine at 6.2 liters and 436 HP is slightly more compact than the M3 unit, and according to manufacturers' published weights, it's a tad lighter at 435 pounds vs 445 for the bimmer. In short, it's safer to go example by example instead of broad strokes.

Originally Posted by MKE_M3

Additionally, there are gearing advantages to high revving engines, the car revving to 8000 RPM can get twice the mechanical advantage (half as tall of gears) as the low revving engine while covering the same speed in each gear.

Lower gearing is better for sports cars.

Mechanical advantage is essentially of no importance in this type of venue. It's power and weight that matter at any given instant. As an example, take an M3 at 8300 rpm, side by side with another identical car (save for engine and gearing) making an equal 414 HP, only at 4150 rpm. These cars will accelerate equally at that instant, with the low revving powerplant making twice the torque with half the gearing.

I do admit that the lower revving car would likely have an advantage at that point since it would likely have less rotational inertia, only needing half the rev increase for any given gain in speed, but I hope you get my point about horsepower and weight, regardless of gearing (i.e. - mechanical advantage).

Originally Posted by MKE_M3

So if you like light cars that are aided by mechanical advantage, then high revving is for you

Most folks in this venue would tend to like light cars, but nobody directly cares about mechanical advantage. I don't think anybody objects to high revs, though, unless that characteristic robs low rpm power.

Bruce

[MKE_M3]

Originally Posted by bruce.augenstein@comcast.

There are some difficulties with this explanation. First, let me change the pairing. Let's use the current Corvette ZR1 engine paired against the four liter M3 engine.

The ZR1 makes 604(!) pound feet of torque, or a little more than double the M3 figure. That means the ZR1 clutch needs to be a bunch beefier than the M3 unit, and it also means the transmission input shaft needs to be very beefy, and/or made out of unobtanium, and/or heat treated to within an inch of its life.

However, consider that the first gear ratio of the ZR1 is at 2.29, vs the M3 ratio of 4.06. First, the torque capacity of a given transmission varies depending upon its first gear ratio - meaning that multiplication of torque is trying to tear the rest of the transmission apart. One of the ways you increase the torque capacity of a transmission is to numerically lower the gear ratios, and the Vette is a prime example of this. The Grand Sport's transmission is rated at around 480 pound feet of torque with its 2.95 first gear, but the ZR1 box (same case, gear sizes, etc.) is rated to take 600 foot pounds, in large measure because of its 2.29 first gear ratio.

Yes, there are other changes, but the ratio change is the biggest enabler. The Vette trans weighs around 220 pounds, while if memory serves, the M3 box comes in a a hair over 200, largely because it needs to be beefy to enable that aggressive first gear ratio.

Now, let's compare torque at the transmission output. In the Vette, it's a massive 1383 pound feet, but wait!, the M3 shows a not inconsequential 1198 pound feet (295 X 4.06), meaning the Vette is only showing about 15% more thrust at that junction. 15% means that the differential and half-shasts need to be beefed up, but not by a ton.

My overall point on this is that big torque requires less aggressive gearing, so driveline weights don't change very much. Consider the ZR1, with more than double the M's torque, only needs 15% beefier components, except for the transmission input.



In general, I agree, but consider that the Corvette Grand Sport engine at 6.2 liters and 436 HP is slightly more compact than the M3 unit, and according to manufacturers' published weights, it's a tad lighter at 435 pounds vs 445 for the bimmer. In short, it's safer to go example by example instead of broad strokes.



Mechanical advantage is essentially of no importance in this type of venue. It's power and weight that matter at any given instant. As an example, take an M3 at 8300 rpm, side by side with another identical car (save for engine and gearing) making an equal 414 HP, only at 4150 rpm. These cars will accelerate equally at that instant, with the low revving powerplant making twice the torque with half the gearing.

I do admit that the lower revving car would likely have an advantage at that point since it would likely have less rotational inertia, only needing half the rev increase for any given gain in speed, but I hope you get my point about horsepower and weight, regardless of gearing (i.e. - mechanical advantage).



Most folks in this venue would tend to like light cars, but nobody directly cares about mechanical advantage. I don't think anybody objects to high revs, though, unless that characteristic robs low rpm power.

Bruce

I think my points are validated by the choice of low displacement, bore > stroke, high revving engines in all true performance applications, i.e. Formula 1, sport bikes, etc. I know the differance may be small, and anecdotally there are exceptions to my points, but they are generally true. As an aside, maybe they are biased since I heard them from an M engineer several years ago, LOL! I appreciate you analysis, however. It would be interesting to compare the drivetrain weight, from engine to hubs of the vette and m3 MT. Not totally fair since they aren't in the same class, and the M3 needs to carry a fair amount more weight, but it would be interesting none the less.

[jerseygirl]

Originally Posted by Munit

So I am the first to say I am and was extremely disapointed when bmw took the turbo route to all M cars and no longer will be the days of RPMS soaring to 8400 or higher. I just don't get how porsche can get 450hp out of a NA flat 6 with less displacement. But that is not the point.

Although there are several things I objectively like about high-revving engines, when I think about it, it actually isn't so clear as to "why" we like it.

Naturally I am not referring to throttle response as that is more of a NA thing and not a high revving thing. Aside from that. Many even say they would have been ok with a turbo v8 revving to 8k but again why?

For me the reasons were straight forward.
1. Probably the most important to me is the sound of the engine and car that you cannot get in any other setup. I really enjoy sound every single drive in this car.
2.the "special" feeling of being somewhat "near" race-car like feel. Nascar actually does not rev much higher than ours. Obviously F1 does but nonetheless it gives you a bit of that "race-car" like feel which makes it feel special each time you drive, atleast for me.

But in the end, while I will miss it, I guess I can't say the important things besides throttle response which seems to be getting better with each engine, will really be negatively effected. Curious other poeples reasons for liking the high-revving nature?

i wont miss it because i still have it. however i find i drive the loaner car a 328 or a 335 much faster than the M3 because of the sound. the quieter engine allows me to push faster as opposed to the roaring M3 V8 which shuts me down . strange isnt it

[e1000]

Originally Posted by jerseygirl

i wont miss it because i still have it. however i find i drive the loaner car a 328 or a 335 much faster than the M3 because of the sound. the quieter engine allows me to push faster as opposed to the roaring M3 V8 which shuts me down . strange isnt it

Earplugs.


S65 is a gem of an engine. Ask anyone that really knows engines what they want a torque curve to look like and it would turn out like the one the S65 produces. While it doesn't make the most power, there's something to be said about it's eight individual throttle butterflies that produce a near instantaneous response. If you really want to understand why the e9x M3 keeps winning comparison after comparison, almost to the point where it doesn't seem fair, it's because of this responsiveness. BMW gives drivers the right options of a traditional 6-speed and excellent DCT to accompany this powerplant.

I'm sure the future turbo engines will be great, but for certain, the NA S65 and S85 engines will both be missed.

[bruce.augenstein@comcast.]

Originally Posted by MKE_M3

I think my points are validated by the choice of low displacement, bore > stroke, high revving engines in all true performance applications, i.e. Formula 1, sport bikes, etc. I know the differance may be small, and anecdotally there are exceptions to my points, but they are generally true. As an aside, maybe they are biased since I heard them from an M engineer several years ago, LOL! I appreciate you analysis, however. It would be interesting to compare the drivetrain weight, from engine to hubs of the vette and m3 MT. Not totally fair since they aren't in the same class, and the M3 needs to carry a fair amount more weight, but it would be interesting none the less.

Maybe in fact you are biased. You say all true performance applications are low displacement oversquare designs, but what about NASCAR, NHRA, those crazy Aussies, etc.? Are those not true performance applications?

On the street, do you know of any exoticars that use small engines?

Look, if you have a strong preference for limited displacement and high revs, that's OK with me, but you haven't made a general case that those engines are inherently "better". In fact, as I've mentioned in the past, the M3 would be a better performer while getting better mileage if it just had a stock Corvette Grand Sport engine under the hood.

Bruce

[MKE_M3]

Originally Posted by bruce.augenstein@comcast.

On the street, do you know of any exoticars that use small engines?

NASCAR and NHRA have max engine sizes, and I'm sure they target high power bands vs. low end torque within the very limiting restrictions they operate under.

Porsche's and Ferrari's come to mind, and I wouldn't call Honda S2000's exotic, but all three of those manufacturers build high specific output NA engines when they very easily could build torque monsters. The most exciting porsche to most people on this forum seems to always be the GT3, even over the GT2. The most exciting Ferrari to most is the Italia, which has a smaller motor than a $30k Mustang GT. Other street "exotics" I can think of are sport bikes. How many sport bikes use torquey V-twins, and how do they compare to the high revving BMW and Japanese four-bangers in performance?

[RingMeister01]

I pulled the trigger on my '13 M3 for the same reason as when I purchased my '08 GT3. The engine. The razor sharp response, the noise, the ticking at idol, just answers what the engineers intent was. Racing experience. These cars are like Olympic athletes, focused to the goal of winning and nothing more. Gives me goose bumps.

[US///M3]

Originally Posted by Munit

So I am the first to say I am and was extremely disapointed when bmw took the turbo route to all M cars and no longer will be the days of RPMS soaring to 8400 or higher. I just don't get how porsche can get 450hp out of a NA flat 6 with less displacement. But that is not the point.

Although there are several things I objectively like about high-revving engines, when I think about it, it actually isn't so clear as to "why" we like it.

Naturally I am not referring to throttle response as that is more of a NA thing and not a high revving thing. Aside from that. Many even say they would have been ok with a turbo v8 revving to 8k but again why?

For me the reasons were straight forward.
1. Probably the most important to me is the sound of the engine and car that you cannot get in any other setup. I really enjoy sound every single drive in this car.
2.the "special" feeling of being somewhat "near" race-car like feel. Nascar actually does not rev much higher than ours. Obviously F1 does but nonetheless it gives you a bit of that "race-car" like feel which makes it feel special each time you drive, atleast for me.

But in the end, while I will miss it, I guess I can't say the important things besides throttle response which seems to be getting better with each engine, will really be negatively effected. Curious other poeples reasons for liking the high-revving nature?

How about BMW super charging the S65?

[bruce.augenstein@comcast.]

Originally Posted by MKE_M3

NASCAR and NHRA have max engine sizes, and I'm sure they target high power bands vs. low end torque within the very limiting restrictions they operate under.

Porsche's and Ferrari's come to mind, and I wouldn't call Honda S2000's exotic, but all three of those manufacturers build high specific output NA engines when they very easily could build torque monsters. The most exciting porsche to most people on this forum seems to always be the GT3, even over the GT2. The most exciting Ferrari to most is the Italia, which has a smaller motor than a $30k Mustang GT. Other street "exotics" I can think of are sport bikes. How many sport bikes use torquey V-twins, and how do they compare to the high revving BMW and Japanese four-bangers in performance?

Look, I addressed your original note, and explained point by point, very specifically - and politely - how your logic might be somewhat off.

Instead of either agreement or a fully reasoned rebuttal, you give me "I think my points are validated by the choice of low displacement, bore > stroke, high revving engines in all true performance applications, i.e. Formula 1, sport bikes, etc."

Then you state only those performance applications that bolster your opinion, and ignore other examples. Give me a break, here.

Listen, I brought up the ZR1 example to demonstrate how insanely high torque outputs don't typically result in driveline weight gains in any linear way - and precisely why that is so.

Now you say "NASCAR and NHRA have max engine sizes, and I'm sure they target high power bands vs. low end torque".

Well duh. Max power per unit of displacement is only reachable at higher rpm, whether force fed or NA. Torque monsters are valueless in a race environment, as long as speeds are high. Horsepower is the only arbiter when speed is part of the equation, so high specific output is mandatory. It's that simple.

Yes, I guess you could classify the ZR1 as a torque monster - but fortunately it's also a power monster.

I remind you that you are the only one talking about "torque monsters" here. Sheer power is what rules, whether it's developed at 8300 rpm or 4150.

Bruce

[Vic311]

Originally Posted by US///M3

How about BMW super charging the S65?

Now that is something I'd like to see. So many very good makes come from the factory supercharged..I wonder why M doesn't take a hand at it?

[Sean Alexander]

For me: Linear torque curve, throttle response, revs, intake sound, intake sound and intake sound!

[Class-of-2016]

For me, the S65 represents BMW's last pure effort to linking its racing technology to everyday car engines. A time where "performance" was the only consideration. Where the "means" was just as important as the "ends".

A force induction M will be fast I'm sure, but will somehow miss in delivering the frenetic F-1 feel of a NA motor. It will truly be missed. OR maybe I'll keep her and get the M4 as my "beater" car.

[MKE_M3]

Originally Posted by bruce.augenstein@comcast.

I remind you that you are the only one talking about "torque monsters" here. Sheer power is what rules, whether it's developed at 8300 rpm or 4150.

No need to get defensive, I guess we are just looking at if from different perspectives. The idea that identical power developed at 8300 or 4150 is identical is absurd based on pure physics as it would be necessary to have one engine double the torque of the other. If that is possible without forced induction or without increasing weight via significantly larger engine size, I've never seen it in practice or in theory. (assuming similar costs/technology are at play) If high specific output doesn't matter, only power, then why do the most elite sports car companies make street cars with high specific output motors? Why not just make the biggest motor and save a ton of money in development costs. Again, consider the power Ferrari could get out of a 5 liter or 6 liter or 7 liter or 8 liter... Yet they choose sub 5 liter engines for their most track focused cars.

I'm curious what your theory is on why Ferrari doesn't use huge engines to develop max power. My guess is that they are trying to be efficient with the power to weight ratio. Sure, Bugatti has their quad turbo W16 monster, but that is not a track focused platform. It is the ultimate GT, which has different priorities over sports cars.

[italyix]

Originally Posted by Mike Benvo

I have my redline set at 8,800 even though I only really go to 8,600 before the shift. The car has seen this RPM a handful of times. Runs stronger than ever

A car I tuned that came to me a few weeks ago (which had stock software w/8,400 limit +/- 100) recorded the highest REV I've EVER seen in an M3, 9,114 RPM! I've read the freezeframe data from hundreds of M3's, and never saw anything like that. This is a testament to how well built these motors are considering it's still running fine 20000 miles later.

Mike, when I took mine in to the dealer for a misfire, a PUMA case was opened cause they could not figure out what was causing this. Turns out the computer recorded an over rev of 12k rpm (from previous owner) and a broken valve spring was causing the misfire. Even BMW was skeptic about the over rev, but car (knock on wood) still runs fine.

[bruce.augenstein@comcast.]

Originally Posted by MKE_M3

...The idea that identical power developed at 8300 or 4150 is identical is absurd based on pure physics as it would be necessary to have one engine double the torque of the other. If that is possible without forced induction or without increasing weight via significantly larger engine size, I've never seen it in practice or in theory.

I've already mentioned the LS3 small-block Chevy which is more than twice the cubic capacity of the M3 engine at 6.2 liters, weighs a little less, is slightly more compact and makes a bit more power (436 HP) - at 5900 rpm. To make that kind of power at 4150, you'd need another small block Chevy with more capacity. Blocks are available at up to 7 liters (and they all weigh within around 20 pounds of each other), so making 414 HP at 4150 rpm would be childishly simple. Of course you'd have to run a very detuned version of such a motor, which Chevrolet doesn't do.

Originally Posted by MKE_M3

If high specific output doesn't matter, only power, then why do the most elite sports car companies make street cars with high specific output motors? Why not just make the biggest motor and save a ton of money in development costs. Again, consider the power Ferrari could get out of a 5 liter or 6 liter or 7 liter or 8 liter... Yet they choose sub 5 liter engines for their most track focused cars.

European engines have a many decades long history of getting more power out of low cubic capacity, largely dictated by laws dating way back which restrict cubic capacity via usurious taxes. If you wanted to make good power, you had to go for rpm, which cam-in-block engines don't do very well by comparison to OHC engines. There are also a number of race venues that restrict engine capacity, so rpm is the solution to that problem.

...and by the way, have you noticed that Ferrari is building some larger engines nowadays?

Originally Posted by MKE_M3

I'm curious what your theory is on why Ferrari doesn't use huge engines to develop max power. My guess is that they are trying to be efficient with the power to weight ratio. Sure, Bugatti has their quad turbo W16 monster, but that is not a track focused platform. It is the ultimate GT, which has different priorities over sports cars.

I have no clue as to why Ferrari does what it does (other than tradition already mentioned), but as long as you're talking about racing, how could the lowly pushrod Vettes beat up on Ferrari, BMW, et al in the 2012 ALMS series, GT2 class?

They also dominated GT1 for many years. How is that possible?

Look, I'm not saying very high revs are in any way undesireable, just not always necessary. In fact, the M3 engine is a world class powerplant - but so is the Merc 6.2 liter, and so is the Z06 7 liter.

Look, this all started with me pointing out my disagreements with most of the basic points in your initial post - which by the way you have not yet refuted in any meaningfull way.

Why don't you?

Bruce

PS - Just remembered those 7 liter Ford GTs back in the sixties that beat the crap out of the Ferraris. My point in mentioning that is to show that few things are absolute.

[BPMSport]

Originally Posted by italyix

Mike, when I took mine in to the dealer for a misfire, a PUMA case was opened cause they could not figure out what was causing this. Turns out the computer recorded an over rev of 12k rpm (from previous owner) and a broken valve spring was causing the misfire. Even BMW was skeptic about the over rev, but car (knock on wood) still runs fine.

Holy cow!

If you are ever down in the socal area, please let me know. I want to read that for myself. Will only take 2 minutes

If 12K rpm only gets you a broken valve spring then these things might as well be bulletproof!!

[shoei]

not a day goes by that i don't miss my M... i've had the luxury of driving cars most kids have posters of on their walls, or i've destroyed those same cars with my motorcycles, but there was just something about my M that always put a smile on my face...

currently, in the garage there is a '13 535 MSport and a '13 335 MSport (6MT) and neither of them give me the feeling i used to have with my M... just about the only thing i prefer more is i am not going to the gas station every 48 hours now, in fact, i made it from LA to SF in the 535 on about 3/4's tank of gas, and i tend to drive like a ride a motorcycle...

as for the GTR, i've logged now at least 2500 - 3000 miles on a black edition... this car is WICKED fast, grips like the tires are coated in gorilla glue to the pavement, you just cannot make a mistake in this car... what i mean is, the car just won't let you make a mistake... literally... well, except this one time...



anyways, back to the subject at hand... IN A STRAIGHT LINE this car is so much fun, it's insanity... closest feeling you will get to what its like full throttle on a motorcycle... however, the rest of the driving is SO detached from the driver, it just seems sureal at times... it's difficult to pinpoint without you having the opportunity to log some serious miles in the car... when you compare it to one of his other cars, namely the CL65, that thing has this ridiculous amount of torque, but when you actually DRIVE it, you get that sensation of "the car is trying to murder me" anytime you give it gas in a turn or a curve... you miss that sensation in the GTR...