[tennisfreak]

Originally Posted by XutvJet

The B58 has adopted many of the design elements of the M3/M4 S55 motor like air/liquid intercooling and a closed deck block. The standard issue S55 makes around 420whp and 400wtq. That motor runs twin turbos and a ton more heat management systems. Sure, some are to compensate for racing, others are there for motor longevity because of the big power. Yes, you can turn up the wick on a B58 and get a near S55 like 400whp, but in the long-term, the motor and turbo aren't going to be happy about it. If BMW intended the B58 to make 400whp, or basically 470hp at the flywheel, they would have certainly gone with twins to reduce the strain on the turbo to meet long-term reliability goals. Same goes for the cooling and ignition systems. Also, the ZF 8AT in the M240 isn't designed for that amount of torque. It will certainly break if you drive the car hard on an often basis.

And I would counter you with BMW limiting the B58 to 335hp due to product stack and alignment.

They cannot release a m240i that out powers their M2 product without throwing their lineup out of whack.

Its been proven many many times over throughout the history of auto manufacturing that often products are released with engines and drive-trains capable of much more than stock.

[XutvJet]

Originally Posted by tennisfreak

And I would counter you with BMW limiting the B58 to 335hp due to product stack and alignment.

They cannot release a m240i that out powers their M2 product without throwing their lineup out of whack.

Its been proven many many times over throughout the history of auto manufacturing that often products are released with engines and drive-trains capable of much more than stock.

Yes, the "335hp and 369tq" M240 and the 365hp/369tq M2 both make closer to 380hp/390tq (they essentially put down the same power to the wheels; the M2 weighs about 120lbs lighter though). The M235 320hp/330tq makes closer to 360hp/380tq. BMW has historically underrated their turbo motors since the introduction of the N54 motor.

BMW most certainly "limits" the power in turbo motors. For one, to easily offer minor OEM power upgrades like the M Performance Power Kit (MPPK) such as in the 340 and 440 (the M235/240 already come with the MPPK tune as stock). It's a great money maker.

Secondly, BMW goes to great lengths with it's tuning strategy to deliver a naturally aspirated-like power curve. They definitely remove some power in the low and midrange to a give a more linear power delivery and give a sensation of building power rather than a sledge hammer. It also helps to tractability when racing. When you add a tune or piggyback, much of the gain comes in the low and midrange with far less gained in the upper rpms. That's because the turbo is being pushed harder and is reaching it's max efficiency. If you really push the boost and add other mods, you can also wreck the intended power delivery and can make the motor feel like it's running out of breath on the topend. The power can hit really hard in the low/midrange to the point that the tires are fighting for traction, especially in the turns.

Yes, M235/M2 N55 and B58 short blocks can definitely handle quite a bit more power than stock. They both have forged cranks and rods, the pistons are strong, and the blocks themselves quite robust (yes, even the open deck N55). Thing is, there's a lot more that goes into it reliable power and motor longevity. Adding a lot more power creates a lot of heat and increased demands on the ignition and fueling systems. You're also venturing outside of the DME safety net. With stock and minor power enhancements, the DME can keep things in check like detonation. Once you add a lot more power than stock (i.e., 20%+), you're walking on egg shells. Boost comes on much harder and faster and there's simply more of it, fueling and ignition systems struggle to keep up, more heat and cylinder pressure is generated in the combustion chamber, heat management systems struggle to keep up, etc. Everything is getting and pushed harder. That's a fact. A stock or lightly tuned turbo BMW motor will certainly live a much longer life on average. It's amusing to me when people say, "well I've been running a lot more power than stock for 10K miles and have no issues". Yeah, I believe it, but what about 2 to 3 years down the road or 30-40K miles? You're also potentially one super-knock event away from a broken piston, bent rod, or spun rod bearing because the DME can't keep it in check.

[tennisfreak]

While you make valid points the mere fact that BMW has a relationship with Dinan is proof their engines and power-trains can reliably handle more power.

If more power was truly a concern then I doubt BMW would offer Dinan products at the dealership and even sell them off the floor installed on brand new vehicles.

And there is huge difference between a Dinan sport tune and a Dinan stage 1 tune.
The number of sensors monitored are increased with a full stage 1 dinan tune.
They are doing much much more than just increasing the boost to make sure the vehicle is getting a safe and reliable output increase.

[XutvJet]

Originally Posted by tennisfreak

While you make valid points the mere fact that BMW has a relationship with Dinan is proof their engines and power-trains can reliably handle more power.

If more power was truly a concern then I doubt BMW would offer Dinan products at the dealership and even sell them off the floor installed on brand new vehicles.

And there is huge difference between a Dinan sport tune and a Dinan stage 1 tune.
The number of sensors monitored are increased with a full stage 1 dinan tune.
They are doing much much more than just increasing the boost to make sure the vehicle is getting a safe and reliable output increase.

The key word here is "relationship". Assuming you bought a Dinan component with their warranty coverage, Dinan will cover the cost of a repair if BMW believes the Dinan component was responsible for the failure. That's why BMW and Dinan have the relationship. BMW doesn't give Dinan any special privileges such as peering into the DME or other components.

I do agree, the Stage 1 and above piggybacks do monitor a lot more parameters than the simple Dinan Sport. It was never clear to me what all the Stage 1 and above piggybacks are actually modifying in terms of other parameters, but they no doubt deliver more overall power and probably better driveability.

With all this said, the most common major issues people have with adding substantial power (i.e. 20%) to the N54 and N55 cars are:

1) Broken front differentials in xdrive cars
2) Broken 6AT and 8AT transmissions
3) Smoked clutches and broken/glazed dual mass flywheels
4) Broken half shafts
5) Spun rod bearings
6) Bent/broken rods
7) Lifted heads and subsequent headgasket failure
8) Cracked cylinder liners

The B58 will likely prove no different, except for perhaps the cylinder liner issue, when you start pushing more of them harder and longer with power mods.

[Sportstick]

Does Dinan have some relationship with BMWNA or BMWAG? I don't think so, but could be wrong. Dinan has wisely targeted BMW dealers to carry their product line, and has offered their own Dinan warranty in case BMWNA demurs. BMW dealers are not "BMW". They are independent business entities who have a franchise relationship with BMWNA, and who (unless proscribed by franchise agreement) may enter into other third party contracts, such as with Dinan, or with whomever plows the snow or fills the coffee machine in the showroom. The mere fact that a dealer may also represent Dinan does not imply anything about the stance BMWNA nor BMWAG takes on this issue. A BMW dealer I know dropped their relationship with Dinan recently.

[VIN240i13]

Originally Posted by Sportstick

Does Dinan have some relationship with BMWNA or BMWAG? I don't think so, but could be wrong. Dinan has wisely targeted BMW dealers to carry their product line, and has offered their own Dinan warranty in case BMWNA demurs. BMW dealers are not "BMW". They are independent business entities who have a franchise relationship with BMWNA, and who (unless proscribed by franchise agreement) may enter into other third party contracts, such as with Dinan, or with whomever plows the snow or fills the coffee machine in the showroom. The mere fact that a dealer may also represent Dinan does not imply anything about the stance BMWNA nor BMWAG takes on this issue. A BMW dealer I know dropped their relationship with Dinan recently.

Your assumption is correct, the relationship is a "per dealership" arrangement. I have only three BMW dealerships with a 100 mile radius and of those three only ONE offers Dinan products. For the remaining, the dealership where I purchased my car is to new, and the other canceled their Dinan relationship due to slow sales of their product.

[Luftwaffe1O1]

There isn't a true relationship, more of a loose agreement I thought. Basically Dinan offers to cover the work if BMW says no. That's their warranty coverage. But keep in mind it also only follows the original 4/50k warranty, and is my understanding, does not move upwards if you extend your warranty to 6, 7, or 8 years.

Nevertheless it is a still a good idea if you mod the car early enough in its life, as there are issues that you could have that BMW could likely try and blame on the aftermarket parts. Like the Charge pipe bursting etc.

[Maynard]

Do a search on here, but IIRC, DINAN was also starting to pull back from these warranties unless easily attributed directly to their parts, leaving purchasers in the lurch for things like transmission/diff problems (i.e. in the same position as every other modder). Used to be that part of that whole 'real men mod cars' ethos was the understanding that once you start re-engineering your car, you buy the repair ticket. I suspect that future buyers (i.e. many of us) will be paying the price for this 'get the dealer to pay for repairs of modded cars under warranty' - hence the shortened warranty periods, and probably soon to routinely scan for the codes that tip them off to prior mods.

[Sportstick]

Originally Posted by Luftwaffe1O1

There isn't a true relationship, more of a loose agreement I thought.

There are four possible parties, each an independent entity:

1. BMWNA
2. BMW Dealer
3. Dinan
4. Consumer

Between whom do you find a "loose agreement"?

[tennisfreak]

Well I have modded many cars and you always have to be prepared to accept the risk of paying out of pocket when things break.

Fortunately for me I have not had to encounter that issue yet.

If my car breaks and both Dinan/BMW refuse to honor warranty I'll gladly come back here and let you tell me "I told ya so".

Until then I'll keep my tinfoil hat off and enjoy my car running the Dinan Stage 1 tune.