Why water cooled on the GTS?

[01101001]

If aftermarket engine tunes are actually reliable, and don't result in damaging engine internals, premature wear, DCT slippage/wear, etc, then why do you suppose BMW engineers didn't go that route instead of spending a massive fortune in R&D to make a water cooled engine.

To me it seems BMW engineers looked at the S55 and said "we're stuck... we've sucked all we can out of this safely... and the only way to get more SAFELY that we can warrantee is water cooled"

I'm sure BMW would have been thrilled to do a simple engine tune, perhaps some upgraded turbos, and suck out another 100 hp, for a mere $5,000 per car, then raise the price $50,000 and pocket the sweet $45,000 profit.

They wouldn't have to tell people what they did exactly... they could just call it a secret in-house recipe (wink wink) that they bought from Pure and BurgerTuning and rebadged.

[bd307]

They need to find a way to pay the peeps at the marketing department.

[SYT_Shadow]

There is no doubt that what an OEM does to allow X hp is extremely different than what an aftermarket 'tuner' does to gain 5X

Although some aftermarket tuners are very reputable, I do not doubt it reduces the life of the engine. Whether that matters or not is also another matter, as no one plans on putting 300k on their S55

[CanAutM3]

The S55 is able to compensate for poorer atmospheric conditions and/or when submitted to extreme use such as seen on a race track. The intercooler on my car stays cool to the touch even after extensive track use in 100 degree weather. That means the engine has a fair bit of thermodynamic margin. Tunes simply tap into that thermodynamic margin to produce more power under ideal conditions. That means that under heavy use with hot and low baro conditions, the tuned engine will likely not be able to sustain the power it makes in ideal conditions. I believe that BMW resorted to water injection so that the GTS is still able to belch out its 493hp even with sustained track use in less than ideal conditions.

[Flacht3]

Performance reasons aside, it's likely also because it's basic R&D. Put the money and manpower towards developing something brand new and high-end on your $130,000+ exotic model so once you've already covered the upfront costs of engineering you can then start to tune it for other models. Don't be surprised when you see the tech in future M engines thanks to the M4 GTS essentially bankrolling the development.

[01101001]

Originally Posted by SYT_Shadow

I do not doubt it reduces the life of the engine. Whether that matters or not is also another matter, as no one plans on putting 300k on their S55

Yes, I've had discussions with people on YouTube who have confessed that their 700 hp F80 M3 is leased, and they really don't care what happens to it, because they'll just remove everything when they turn it in. It's people like that that are the reason I'll never buy used.

[01101001]

Originally Posted by CanAutM3

The S55 is able to compensate for poorer atmospheric conditions and/or when submitted to extreme use such as seen on a race track.

Good points about the cooling... you actually answered my question more specifically than I intended. I don't know if BMW beefed up the DCT, or other internals when they made the GTS, but if tuners are pushing more torque at the DCT that's already at it's limit stock (from other threads i've read), then I can't imagine how higher boost and torque aren't doing some damage somewhere along the engine/tranny.

[01101001]

Originally Posted by ItIsChrisM

Don't be surprised when you see the tech in future M engines thanks to the M4 GTS essentially bankrolling the development.

But I wonder if in this case that wasn't money down the toilet. Isn't BMW looking at hybrid/electric means to add more power... perhaps a motor at the wheels for instant torque. I don't see them 10 years out doing anything with water cooling. I dunno, just seems like a really stupid move when the rest of the world is going to exponentially head towards hybrid/electric power.

[AlterZgo]

Where do you get this "massive fortune" spending idea from? Water and meth injection has been around for decades and it is super easy to implement cheaply. It is very basic, effective technology. In fact, so cheap that you can buy an aftermarket kit that works just as well and get the same benefits on a regular M4.

Also, your term "water cooled engine" applies to every BMW and 99% of the cars on the market today. They are ALL water cooled. The last air cooled car I can think of is the 911 from the 90s.

You are correct that the engine mods didn't cost BMW all that much - likely less than even the $5k per car you estimate for just an engine tune. But, the GTS is not just the water injection. It has many other upgrades such as the KW club sport suspension, roll cage, carbon fiber and other aero bits, upgraded exhaust system, oled tail lights, etc. Still, BMW is making a huge profit off of each car because it did not really cost them all that much more to develop. Plus BMW will trickle down some of the parts to other M4s and M3s down the road further spreading out their development costs beyond the 800 GTS models sold.

[gingerbread]

More power and lower emissions .... Key word emissions.

[01101001]

Originally Posted by AlterZgo

...

"Where do you get this 'massive fortune' spending idea from?"

Inferred from things I've read. I'm not allowed to post links apparently, but in one article BMW mentions they will be "using this technology for the first time"
So I'm assuming there was substantial money involved in...
1. the engineers designing the changes,
2. the CAD people drawing the changes,
3. building and testing the changes for reliability,
4. retooling their manufacturing process/equipment for a mere 800 cars that have this modified engine.
etc. etc.

"Water cooled engine"

Yes... poor choice of words that does not reflect the actual process.
What I meant was INJECTING water... what they are actually doing.

"In fact, so cheap that you can buy an aftermarket kit that works just as well and get the same benefits on a regular M4"

Then I wonder why I haven't seen people doing that on YouTube or elsewhere. All I see are the typical mods. Aftermarket tune/remap, fuel change, perhaps Pure turbo upgrade. Maybe I haven't looked hard enough, but I haven't seen anyone modifying their F8X engines for water cooling.

[dzvero]

Originally Posted by gingerbread

More power and lower emissions .... Key word emissions.

They also got more power with same mileage/gallon means its more fuel efficient . Its the image they need to advertise, not the 100 hp more power with twice the gas to get it .

[SYT_Shadow]

Originally Posted by AlterZgo

Where do you get this "massive fortune" spending idea from? Water and meth injection has been around for decades and it is super easy to implement cheaply. It is very basic, effective technology. In fact, so cheap that you can buy an aftermarket kit that works just as well and get the same benefits on a regular M4.
.

I completely disagree. The injectors BMW is using in the GTS are diesel injectors which I'm sure cost, per unit, more than the aftermarket stuff people are selling.

If this were so easy to replicate, many shops would be selling the GTS equivalent and I haven't seen it yet

[CanAutM3]

Originally Posted by 01101001

Good points about the cooling... you actually answered my question more specifically than I intended. I don't know if BMW beefed up the DCT, or other internals when they made the GTS, but if tuners are pushing more torque at the DCT that's already at it's limit stock (from other threads i've read), then I can't imagine how higher boost and torque aren't doing some damage somewhere along the engine/tranny.

The DCT in the F8X is the same unit as in the M5/6 and is rated at 700N-m (516lb-ft). So the DCT internal are able to manage the torque. A different DCT software tune may be needed to adjust the clutch clamping force/speed to deal with the extra torque.

[bruce.augenstein@comcast.]

Originally Posted by dzvero

They also got more power with same mileage/gallon means its more fuel efficient . Its the image they need to advertise, not the 100 hp more power with twice the gas to get it .

This is a common misconception. The GTS is probably about as fuel efficient as the standard M4, but only BMW knows the exact numbers. In this case, the exact numbers are calculated using BFFC, or "Brake Specific Fuel Consumption" numbers.

BSFC numbers are represented by how many pounds of fuel are consumed per hour, per horsepower generated. Nowadays, most performance cars use a bit less than half a pound of fuel per hour per horsepower.

The EPA measures fuel consumption over a calculated chassis dynamometer run simulating either city or highway use. Trust me, both tests are run with way-low acceleration rates, so with car weights so similar, both the GTS and standard M4 need to generate similar low amounts of power to match the needed acceleration/deceleration/coast numbers for the runs.

Because of BSFC, however, when you are out on a track day in your GTS against your buddy in his M4, you're going to be sucking fumes in your car after a couple of sessions while your friend still has a quarter-tank left.

BFSC rules. Ask Audi at LeMans.

Bruce

[01101001]

Originally Posted by CanAutM3

The DCT in the F8X is the same unit as in the M5/6 and is rated at 700N-m (516lb-ft). So the DCT internal are able to manage the torque. A different DCT software tune may be needed to adjust the clutch clamping force/speed to deal with the extra torque.

Ahhh, didn't know that. Good info.

[AlterZgo]

Originally Posted by 01101001

"In fact, so cheap that you can buy an aftermarket kit that works just as well and get the same benefits on a regular M4"

Then I wonder why I haven't seen people doing that on YouTube or elsewhere. All I see are the typical mods. Aftermarket tune/remap, fuel change, perhaps Pure turbo upgrade. Maybe I haven't looked hard enough, but I haven't seen anyone modifying their F8X engines for water cooling.

Search meth injection N54 or S55 you can find kits for well under $1K. Snow performance sells many kits for different cars. You can also find kits from BMS Tuning, etc.

People don't do this more because of lack of familiarity and/or understanding of the performance benefits and that they don't want something that is obvious and intrusive (running meth/water injection cables into the engine bay).

Truth is, meth/water injection lets you boost power significantly while making the car run much safer and more consistently. This is one of the reasons why BMW went with water injection for the GTS.

[Racer20]

Originally Posted by 01101001

If aftermarket engine tunes are actually reliable, and don't result in damaging engine internals, premature wear, DCT slippage/wear, etc,

Because aftermarket tunes DO have all those results, but in order to really prove it, they would have to run a full durability cycle to simulate 120k miles under hot and cold conditions with all kinds of drivers and load conditions, then teardown every part of the car to look at its condition. BMW does this. BMS and everyone else does not. It's unlikely that any of the aftermarket tunes meet BMW requirements for all those things as well as fuel economy, drivability, and all the other things that aftermarket guys don't care about. And most aftermarket companies simply don't have the resources, knowledge, time, or money to test their products nearly as thoroughly as BMW.

[Racer20]

Originally Posted by 01101001

But I wonder if in this case that wasn't money down the toilet. Isn't BMW looking at hybrid/electric means to add more power... perhaps a motor at the wheels for instant torque. I don't see them 10 years out doing anything with water cooling. I dunno, just seems like a really stupid move when the rest of the world is going to exponentially head towards hybrid/electric power.

So is BMW. I3? I8? e Performance version of their latest cars? ActiveHybrid 3, 5, and 7, etc?

Other companies are also continuing development on combustion engines, because for at least another decade, most cars will still use them.

[dzvero]

Originally Posted by bruce.augenstein@comcast.

This is a common misconception. The GTS is probably about as fuel efficient as the standard M4, but only BMW knows the exact numbers. In this case, the exact numbers are calculated using BFFC, or "Brake Specific Fuel Consumption" numbers.

BSFC numbers are represented by how many pounds of fuel are consumed per hour, per horsepower generated. Nowadays, most performance cars use a bit less than half a pound of fuel per hour per horsepower.

The EPA measures fuel consumption over a calculated chassis dynamometer run simulating either city or highway use. Trust me, both tests are run with way-low acceleration rates, so with car weights so similar, both the GTS and standard M4 need to generate similar low amounts of power to match the needed acceleration/deceleration/coast numbers for the runs.

Because of BSFC, however, when you are out on a track day in your GTS against your buddy in his M4, you're going to be sucking fumes in your car after a couple of sessions while your friend still has a quarter-tank left.

BFSC rules. Ask Audi at LeMans.

Bruce

I stated it, BMW claims same mileage . What I meant is more fuel deficient than tuning the engine . And Im aware these numbers are in ideal conditions and ideal driving which you can not meet with everyday driving/drivers

[Mike@N54Tuning.com]

No need to spend $120k+ on a GTS to get nicely integrated water
injection on your M3...

[01101001]

Originally Posted by Racer20

So is BMW. I3 I8 e Performance version of their latest cars ActiveHybrid 3, 5, and 7, etc

Other companies are also continuing development on combustion engines, because for at least another decade, most cars will still use them.

I think you missed my point.
Yes BMW, and others, are all pursuing electric/hybrid and internal combustion... not water injection. Maybe I have no clue what I'm talking about, but in the dark alleys where I read about cars, I've seen no mention of the glorious future of water injection. Hence, if BMW only did this for the M4 GTS, seems like a huge waste of money... well ok, not a waste... they recouped it by massively overpricing the car and letting suckers pay for their waste.