[younghov85]

If you're going below 1500 or 2000 rpm (except when cruising) on a regular basis and actually expect the engine to do something for you down there, you either need to learn how to drive or buy an American car with an enormous, over-sized pushrod V8. Period.

What exactly is a pushrod engine, I had one before (2000 pontiac grand prix Gt) but i just wanna understand the difference?

[akhbhaat]

Originally Posted by younghov85

What exactly is a pushrod engine, I had one before (2000 pontiac grand prix Gt) but i just wanna understand the difference?

Basically, it's a type of engine that locates a single camshaft within the engine block (rather than above it as in an OHC layout), which uses pushrods to apply tension to rocker arms which themselves actuate the cylinder valves. Difficult to explain without looking at a graphic (I provided a link below).

The main advantages to pushrod engines are physical packaging (the block is fairly small given its cylinder displacement) and mechanical simplicity. On the other hand, they have more rotational inertia so pushrod engines have a tendency to float the valves and are generally unable to rev much past 6000 rpm with conventional materials. I just mentioned pushrod because most of the large, torquey American V8s use a pushrod configuration (like the C6 Z06's LS7) and are tuned to deliver large amounts of bottom end torque to compensate for the relatively low rev limit. It is possible to overcome some of the limitations of pushrod designs with clever engineering and the use of appropriate materials (namely stronger pushrods). The LS7 is actually a great example of a fairly high tech pushrod engine.

This site puts it about as well as anybody. Comes with animations and all: http://auto.howstuffworks.com/camshaft5.htm

[imageWIS]

Originally Posted by RR

http://www.topgear.com/content/news/stories/527/

Bumped across this short article a moment ago, thought I should share it with you folks here. May not always agree with their opinions, but they certainly have the knowledge and only declare releases when they are positive about their facts...

Your ‘considering’ options are really funny. Not the actual cars, but the BMW engine choices…

Jon.

[imageWIS]

Originally Posted by Bimmerista

It is impossible not have some turbo lag when using straight turbos like the n54 appears to be.

Direct injection and turbo is already being used by Audi/VW on the 2.0 4 cylinder. While I believe the first use in a 6 cylinder is going to be by BMW, the twinning of the two technologies does not break new ground.

Note that Valvetronic appears to be out for the turbo, but could be retained for the north American non-turbo motor if indeed this is the way things will play out.

I HATE turbo lag and swore off turbos because of that. Frankly, IMHO I hope in NA we get a NA engine, same Hp, valvetronic and DI. That engine would rock !!!

Just my opinion of course.

1) Dual turbo configuration of one small booster turbo and one larger constant turbo will produce very little, if any noticeable lag.

2) On my A4 2.0T, the turbo lag is minimal, if at all, because the engine has a lot of torque for its size (207 lb-ft), thus it pushes through fast enough before the turbo kicks in to allow for almost no (if any) lag. I have yet to feel any lag... and I have driven 911 Turbos's before.

Jon.

[Garrett]

Originally Posted by E90Fleet

only question is what will the USA get, NA or turbo

There is no NA version of the 335i. BMW isn't going to build two different engines just so us Americans can feel happy about cubic inches.

If you'd rather have old tech (cu inch.) then buy a chevy.. if you want new tech then buy a BMW.

[Garrett]

Originally Posted by Bimmerista

It is impossible not have some turbo lag when using straight turbos like the n54 appears to be.

Direct injection and turbo is already being used by Audi/VW on the 2.0 4 cylinder. While I believe the first use in a 6 cylinder is going to be by BMW, the twinning of the two technologies does not break new ground.

Note that Valvetronic appears to be out for the turbo, but could be retained for the north American non-turbo motor if indeed this is the way things will play out.

I HATE turbo lag and swore off turbos because of that. Frankly, IMHO I hope in NA we get a NA engine, same Hp, valvetronic and DI. That engine would rock !!!

Just my opinion of course.

I guess either you havn't read the full press release, or you've failed to understand what BMW has released.

-It's a bi-turbo, meaning that it uses 2 very small lightweight turbos whon FULL torque come into play at 1,500rpm's - 5,800rpm's.

-Hi Pressure high precision Direct Injection fuel delivery system.

-Piezo dispensor (If you seen a modern day Humidfyer, then you can understand how broken up and dispersed the fuel will be in the cylinder, vrs just a spray.

-Brand new engine block

-5% better fuell efficiency than the engine it replaces.

-Increased "smoothness" over previous engine. (if that even was an issue.. but now it even better)

-LIGHTER


Now, Bimmerista.... what would .5 more liters give you over such an impressive engine that BMW engineers just released.

More weight ..?

Less fuel economy ..?

Less torque ..?

Offset the superb balance of the 3-series ..?


All because you CANNOT get over the notion that turbo's are used in AIRPLANES and have been around over 100 years ..?

[Garrett]

Originally Posted by Bimmerista

You may well be right, but I had the A4 1.8T, supposedly one of the better turbos out there and the darn engine felt sluggish under 2300 rpm. So once bitten twice shy - I am for now skeptical of the turbo.

Here is a clue..... -----> It's a 1.8 liter !!!!!!

[Bimmerista]

Originally Posted by Garrett

I guess either you havn't read the full press release, or you've failed to understand what BMW has released.

-It's a bi-turbo, meaning that it uses 2 very small lightweight turbos whon FULL torque come into play at 1,500rpm's - 5,800rpm's.

-Hi Pressure high precision Direct Injection fuel delivery system.

-Piezo dispensor (If you seen a modern day Humidfyer, then you can understand how broken up and dispersed the fuel will be in the cylinder, vrs just a spray.

-Brand new engine block

-5% better fuell efficiency than the engine it replaces.

-Increased "smoothness" over previous engine. (if that even was an issue.. but now it even better)

-LIGHTER


Now, Bimmerista.... what would .5 more liters give you over such an impressive engine that BMW engineers just released.

More weight ..?

Less fuel economy ..?

Less torque ..?

Offset the superb balance of the 3-series ..?


All because you CANNOT get over the notion that turbo's are used in AIRPLANES and have been around over 100 years ..?

I have read the press release:

-DI will mean zilch here for fuel economy until we get the new grade fuels they have in Europe;

-I hope you are right and the press release does not embelish all of the rest of what is claimed; however, the Audi also claimed instant miraculous no gap torque from 1,800 rpm and gues what, there was a turbo lag.

So I hope that Garret is right and the fact that the larger displacement 6 plus twin turbo (smaller turbos) will diminish turbo lag.

All that I am saying is that I will believe when i test drive it not before.


PS I have owned turbos before so I don't get your comment about turbos in airplanes etc. It is not that I do not believe in turbos , I have yet to meet the turbo engine that I like.

[lux.sh]

Few of the bmw's "juiced-out" high-power N/A motors have caused issues in the past already. No need to take such risk on a model which contributes 60% of the company's sales.

just add some forced induction and call it a day.
Its more tuning-friendly anyway.

[mapezzul]

The new DI Audi 2.0T has no turbo lag. It is a great little 4 banger. The 1.8t did not per se have turbo lag but lack of any umph less than 2k. Turbo lag is more of you push the gas and have to wait for the boost to built to get the power, like older Saab's is the best example I can think of off the top of my head; you would step on the gas and have to wait for a bit and then all of a sudden the car went like hell, there was no smooth transition or ability to reliably predict it. I am sure the BMW will have no lag and instant response, those little guys are going to spool real quick! New turbo technology is great!

[younghov85]

i wish people would stop critisizing this new engine from BMW. Technology is only created to make things better and thats what BMW is trying to do. There must me a very good reason for them switching to bi-turbo engine, and it may have to do with emissions, or whatever, but i can guarentee it is for a good reason. I mean when was the last time BMW made a 3-series that wasnt the par setter for other car companies. i think we should just just sit back and relax and wait for the performance experts, BMW, to bring us another world-class BMW.

[RichReg]

Originally Posted by Bimmerista

-DI will mean zilch here for fuel economy until we get the new grade fuels they have in Europe

Just out of curiousity, when are we supposed to get these "new-grade" fuels, and does that mean that the BMW Direct-injection engines can't be brought here until that fuel is available?

[EnI]

Originally Posted by RichReg

Just out of curiousity, when are we supposed to get these "new-grade" fuels, and does that mean that the BMW Direct-injection engines can't be brought here until that fuel is available?

My questions exactly.

Can someone dig out the Tier 2 implementation schedule.

[JamieA]

400Nm of torque = modern NA 4.0l engine, hence BMW's comparison to the 4.0l V8

I like their reasoning of keeing the engine compact for the purposes of protecting their handling - the most important part of BMW DNA in my view.

Also, how could ANYONE bitch about 400Nm between 1500 and 5800 RPM???? That is positively coffee table flat and very broad!!! This thing will pull like a teenager with his first playboy mag...

[bappen2001]

Originally Posted by akhbhaat

These turbines will be spooled and making nearly full boost as early as 1500 rpm and will maintain it well through the engine's rev range. I have enough personal experience with small, low inertia turbines to know that you won't even notice that they're there (outside of a faint whistling sound) if you keep the engine in the meat of the powerband. I mean, hell, 1500-5800 rpm - you'd have to be an idiot or the laziest man alive to let the engine fall below that.

Well said, akhbhaat! I can't believe the whining in this thread.

"Ooooh, BMW just came out with a 306hp biturbo monster, but my 0.5 liter saab/audi/other-car-that-sucks lags with turbo so the bmw will probably lag too - so I'm not going to buy it/like it."

Yeah right.

It's going to rock. This is BMW we're talking about here. Don'tcha think they have worked on this lagging problem quite a lot? Now, that's probable.

.bappen

[JamieA]

Originally Posted by bappen2001

Well said, akhbhaat! I can't believe the whining in this thread.

"Ooooh, BMW just came out with a 306hp biturbo monster, but my 0.5 liter saab/audi/other-car-that-sucks lags with turbo so the bmw will probably lag too - so I'm not going to buy it/like it."

Yeah right.

It's going to rock. This is BMW we're talking about here. Don'tcha think they have worked on this lagging problem quite a lot? Now, that's probable.

.bappen

Exactly... afterall, Motor is their middle name, you couldn't see them releasing an underdeveloped turbo engine, esp as it will go into their (for the moment until the new M3 arrives) hero car in the 3 Series range.

[mapezzul]

Originally Posted by RichReg

Just out of curiousity, when are we supposed to get these "new-grade" fuels, and does that mean that the BMW Direct-injection engines can't be brought here until that fuel is available?

As I stated in another post, the fuels have been rolled out. The US sulfur content in gasoline is 40ppm. Which is greater than that of Europe. We more than likely will NOT see this engine in current form. They are going to need to tweak it for the US market. View the following thread for more info: It explains the reason for low sulfur and the current levels and lack of vlavetronic: Best of Luck!
http://www.e90post.com/forums/showthread.php?t=13350

[hector]

[QUOTE=GregA]So, now we have the whole pic: 306HP N54 in 335i, 330HP N54 in 335si

is the 335si just higher revving with comparable torque to the 335i, running more boost with increased torque and hp or a combination of both?

[EnI]

[QUOTE=hector]

Originally Posted by GregA

So, now we have the whole pic: 306HP N54 in 335i, 330HP N54 in 335si

is the 335si just higher revving with comparable torque to the 335i, running more boost with increased torque and hp or a combination of both?

[RichReg]

Originally Posted by mapezzul

As I stated in another post, the fuels have been rolled out. The US sulfur content in gasoline is 40ppm. Which is greater than that of Europe. We more than likely will NOT see this engine in current form. They are going to need to tweak it for the US market.
http://www.e90post.com/forums/showthread.php?t=13350

O.K., I think I understand. So the bottom line is:

BMW has to not only tweak the engine to accept slightly different sulphur fuel, it still has to get the engine approved for the U.S. So......since 306 Euro hp is probably about 300hp by U.S. standards AND this engine needs to be tweaked to accept U.S. fuel, we could see something like 290-295 hp instead?

If I remember correctly several large manufacturers (including BMW) were fined recently for not meeting U.S. fuel economy standards, so I wonder if they're taking their time a bit to perfect it?

F.Y.I. : Per Autoweek, the E92 Coupe will NOT debut in Geneva.
BMW Unveils Coupe

[Bimmerista]

Autoweek says the cabrio will be unveiled in Paris, which is consistent with a September introduction of the cabrio.

The coupe will be unleashed at Geneva from what I read.

[noflash]

Originally Posted by Bimmerista

The coupe will be unleashed at Geneva from what I read.

I think we have determined that it will not be shown in Geneva. (read that article again )