N55 Faster than N54? And handles better?

[djminkin]

Originally Posted by acs1.35i

The N55 is (slightly) better then the N54 engine. Despite all the technical discussions here, on two points the N55 is better:

1) It performs better at high rev's.
2) It has better gasrespons and less turbo-lag.

This is what I have read in tests so far.

Although I drove the new motor in an X5, there is little to no lag compared to the N54 motor. Big difference.

[OhDasCrazy]

Originally Posted by moff

With actual engine versus engine there isn't really a performance advantage with the N55 is there?

It's the DCT that increases performance, the manual N54 v N55 are the same.

To me, it's clear that this is an efficiency enhancement that lowers CO2 output, decreases fuel consumption and allows for a slightly lower rev max torque output (100 rpm).

I have not read anything by either BMW or the press that suggests that there is an acual engine performance enhancement (not associated with DCT).

Why not get one job to do the same job as 2 turbo's, it makes sense if the performance remains the same?

+1

I'm pretty sure BMW did their Research to make sure that "twin scroll" did the same thing as "twin turbos" and if they couldn't find a equal or greater solution they would have just kept twin turbos.

[OhDasCrazy]

Originally Posted by IZAGLO

how much friggin difference can there possibly be between the N54 DCT 6speed and the n55 7speed?.... and for that matter who would possibly want to buy a step 135 with a auto instead of the DCT....i would never own a BMW if i could not shift it...DCT barely keeps us involved in driving this car, without the paddles it will be just like any auto...boring and i would not own a auto like that....IMO BMW should not even offer it in the 135i....what is next 8 silly gears like the Lexis ...IMO 6 is ALL that is needed in a car...any more than that just gets to much...I am a true manual guy that has shifted for the past 30 years and the 135iDCT is my first car that has the paddles....i dig it ,but i do not want more gears....i want a M3 next and will ONLY buy it with a 6sped manual....And as much as i like the 2011 135i....compared to the N54 is will not be much different...

+1

THANK YOU!!!

DCT is an automatic! There are way too many people getting excited about DCT, hyping it up like its a 7MT! I never drove a car with DCT but Im willing to bet that if you dont touch the paddles or the shifter the car will switch gears for you! BMW offers the 135i in a manual transmission and an automatic transmission. If you dont have 3 pedals at your feet you are driving the auto!

[OhDasCrazy]

Im pretty new to turbo cars, just learned about 3 months ago exactly how a turbo/intercooler setup worked. Didn't grow up with mommy and daddy giving me money to mod out my '94 civic!

Anyway!!! Do most single turbos have 2 scrolls in them? I mean I thought that 1 turbo housing had one scroll in it? So if BMW has this "twin scroll" set up inside one turbo housing, why is no one making the assumption that BMW has designed a single turbo that can replicate the output of a twin turbo setup? Correct me if Im wrong.

[HondaGoneRogue]

Originally Posted by OhDasCrazy

Im pretty new to turbo cars, just learned about 3 months ago exactly how a turbo/intercooler setup worked. Didn't grow up with mommy and daddy giving me money to mod out my '94 civic!

Anyway!!! Do most single turbos have 2 scrolls in them? I mean I thought that 1 turbo housing had one scroll in it? So if BMW has this "twin scroll" set up inside one turbo housing, why is no one making the assumption that BMW has designed a single turbo that can replicate the output of a twin turbo setup? Correct me if Im wrong.

Some of us learned about cars without growing up rich. I traded a set of subwoofers for my first cold-air intake. It is called a hobby or fascination. Or it could also be called research. Most of the rich spoiled kids had shops install all of thier parts so they know less than you think. I turbo'd a CR-X for less than 900.00 myself. Don't make excuses for your lack of knowledge. Internet has been around for a while now.

[Reggie-335i]

Originally Posted by schmeah

Ok, no flaming because this is just a subjective opinion, but I went from a 2007 335i 6MT to a spanking new 2011 135i DCT and can confirm that the N55 with DCT is considerably faster off the line, at least in my hands, than my N54 335i. But IMO it's due to the lightning quick, seamless shifting afforded by the DCT rather than 200 RPM lower peak torque advantage of the N55 or any other feature of the the N55. And I feel no less connected to the engine with the DCT than with the manual tranny. And I've driven nothing but manuals for the last ten years. Oh, and by the way, the N55 exhaust note sounds far better ... coolest exhaust I've ever heard ...

of course the 135i would be faster than a 335i, regardless of the DCT or N55...it is so much lighter than the 335i!!

[dmboone25]

Originally Posted by Reggie-335i

of course the 135i would be faster than a 335i, regardless of the DCT or N55...it is so much lighter than the 335i!!

I think it is about 188 pounds lighter....not that large of a difference IMO....especially when you are talking 3400+ lbs for both....

the 335 also has a lower drag coefficient, thus it is "faster" at higher speeds...it is all relative.....

[REVNU]

Originally Posted by OhDasCrazy

Im pretty new to turbo cars, just learned about 3 months ago exactly how a turbo/intercooler setup worked. Didn't grow up with mommy and daddy giving me money to mod out my '94 civic!

Anyway!!! Do most single turbos have 2 scrolls in them? I mean I thought that 1 turbo housing had one scroll in it? So if BMW has this "twin scroll" set up inside one turbo housing, why is no one making the assumption that BMW has designed a single turbo that can replicate the output of a twin turbo setup? Correct me if Im wrong.

Most turbos made are regular "single scroll". There are few manufacturers that have been using them for a while, Mitsubishi and Subaru (JDM) come to mind. If you do some googling on "Twin Scroll vs Single Scroll", you should come up with more than enough info to build your knowledge base on turbos.