N55 Faster than N54? And handles better?

[RPM90]

Originally Posted by tt135i

TT vs TS. IMO the TT design allows for acceptable low levels of lag with good peak hp with the proper tune. That has shown to be true with the n54 produces 400+ whp with all mods. The TS system is ok at the boost levels (300 hp levels) that the N55 is designed for. The problem is that in order to acheive this relatively minimal lag they had to use such a small single that it won't allow for higher psi and thus higher hp and tq. The problem is that even if you upgraded the single turbo (and that will be an option it's a matter of time)to a larger TS, you could get the higher max psi, but the lag would be much more significant.

Please explain how you know that to achieve minimal lag BMW had to use "such a small single" turbo that it won't allow for higher psi?

BTW, it's already been done. Greater boost levels have been applied to the N55, and it does produce greater power above stock.
So, you are wrong here.

BMW had to use 2 small turbo's to achieve the low lag they did in the N54. This is the reason that high boost levels show great gains in low to mid rpm range, but the OEM turbos don't flow enough to produce high rpm torque, stock or tuned. Tuned, the big low rpm torque is further exaggerated with a big torque spike at low rpm, that only lasts for short rev range, then settles back, continues to around 5k and starts it's big drop that drops even harder around 5700rpm.

Point? The N54 suffers the same problem of small turbos that you attribute to the N55.
How small do you think the TS turbo is? I'm guessing from what you're suggesting, that you think the TS turbo is the same size as one of the turbos from the N54.
If the N55 has a small turbo the size of the N54, as you're suggesting, then how is it capable of producing the same stock HP and torque? A 1 psi difference in stock boost from the N54 to the N55 isn't going to help a small single TS produce the same power as 2 conventional turbos.

Given that the N55 is producing the same stock power numbers, strongly suggests it's a larger single turbo. And that makes sense so that it can flow the needed air to produce those numbers.

[Juicer]

Only time will tell to see the full potential of the n55.

[TwinTurbos]

Originally Posted by TreDirtyFive

Wrong..the M1 has already been tallied to have the N55...also, despite what gospel "tuners" may be giving you, there has already been talk from the big wigs, through the grapevine, as to why the replacement…not only to comply with better emissions standards and the public’s yearning for better mpg, but it’s all about saving the moolah! Cheaper to produce and potentially maintain. If they could, they would’ve put n55s with more power in the IS cars but the N54 performance kits (released long ago) have passed US and international emissions standards long ago…meaning they have paid their dues and duty fees for standardizing it already. That just means they’re trying to get the last invested drops out of this powerplant because it is cost effective and they don’t need to pay to re-standardize an n55 with more power (it costs millions of dollars to do this). Car companies are being very careful how they spend their money these days. A little birdie also already told me stock N55s are out-performing the N54 handily on the test tracks...potentially 40+lbs. lighter and more responsive out of the corners…not to mention it runs much cooler than an n54...go figure.

BMW said there isnt going to be an M1. There will be a 135is just like the 3 series and Z.

[Moo]

Originally Posted by TwinTurbos

BMW said there isnt going to be an M1. There will be a 135is just like the 3 series and Z.

[Thud]

It took BMW how many years to figure out the HPFP on the N54? And the jury is still out on whether it's finally fixed.

N55 is in its first year of mass production now, isn't it? I wonder what problems are lurking 10k-15k miles down the road.

[Thud]

Originally Posted by TwinTurbos

BMW said there isnt going to be an M1. There will be a 135is just like the 3 series and Z.

Who cares what they call it... as long as it's built.

[BSM 335I]

Let's give the N55 a chance. Given the size of the single turbo (being it's probably bigger than one of the n54's tt) the n55 could have more potential in making more power. Think about supras back in the day, the highest hp (1000+) supras have one big T70 or bigger sticking out of the hood. I'm not saying that our n54's can't make the same power, because there's no doubt we can. It's just the n55 would need a turbo swap as our n54 would require supporting mods like a new exhaust manifold and so on. Also if the new valvetronic can be included into new tunes I feel it may be in the n55's favor with that.

I don't honestly think BMW would degrade the next generation of what is already a great selling car. The only manufacturer I've seen degrade one of their own models generation was the civic SI hatch. So i'm pretty sure we'll start seeing tunes within the next 6-12 months. Think about how we started with the jb1, v1, Dinan stg1, and so on.

[BSM Bimmer]

Originally Posted by Thud

It took BMW how many years to figure out the HPFP on the N54? And the jury is still out on whether it's finally fixed.

N55 is in its first year of mass production now, isn't it? I wonder what problems are lurking 10k-15k miles down the road.

The HPFP on the n54 and n55 is the same part number, so there is no advantage on hpfp reliability... a couple people have already had their pump fail on their n55.

[egainer]

Originally Posted by BSM Bimmer

The HPFP on the n54 and n55 is the same part number, so there is no advantage on hpfp reliability... a couple people have already had their pump fail on their n55.

Who do you know that has had their n55 pump fail already?

Threads on here?

[BMW-driver]

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.

[TreDirtyFive]

Originally Posted by TwinTurbos

BMW said there isnt going to be an M1. There will be a 135is just like the 3 series and Z.

Please read this...

The Bimmerpost homepage is your friend..

http://www.bimmerpost.com/m1/

[RPM90]

Originally Posted by Juicer

Only time will tell to see the full potential of the n55.

Absolutely.

I think some people simply handle the concept that perhaps the new engine just might be 'might' be better.
In terms of all around performance and technology, it already is.
Live with it, and be happy that BMW continues to advance it's turbo technology. It benefits the whole brand.
The N54 is already known as a sweet engine, not including the HPFP issue.

[BSM Bimmer]

Originally Posted by egainer

Who do you know that has had their n55 pump fail already?

Threads on here?

I believe it was on the e90post section. I'll try to find the thread...

Edit: it was 335is models so its a 2010 n54.

[RPM90]

Originally Posted by BSM Bimmer

I believe it was on the e90post section. I'll try to find the thread...

Edit: it was 335is models so its a 2010 n54.

Wow, that sucks.

I thought the 335is was a 2011 model?

If it's a 2010 then it might still have the pre 943 pump.
But, if it is the 943, then that does SUCK.

[schmeah]

Originally Posted by RPM90

Wow, that sucks.

I thought the 335is was a 2011 model?

If it's a 2010 then it might still have the pre 943 pump.
But, if it is the 943, then that does SUCK.

It is a 2011 model, but with an N54 (tuned).

[Boosted_N54]

Who Gives A Sh*t If The N55 Is Better Then The N54 Or If Its The Other Way Around . I Dont Need A Dct To Help Me Go Faster Or To Be Fast

......its The Driver That Counts ......

I Have A N54 6spd I Woudnt Mind Racing A N55 Dct. Anybody Up For It??

Then We Talk ..

[gumpy]

If you lived close, I would race you. I have about 700 miles on the DCT 135i and let me tell you there is no way possible you can shift as fast as this transmission. The other difference with the N55 vs. N54 (yes I had a 335xi with N54) is it's low end torque. It is so much better down low. Yes the N54 pulled better mid to high rpm, but with the DCT, you can keep it right in the torque band. Also, you can shift gears mid-corner without upsetting the balance of the car. Also, for autocross, you can downshift into 1st without worries of grinding gears in tight hairpins and go back up to 2nd like lightening. I rode with an old tuner friend of mine who had a Nissan GTR and let me tell you this DCT feels like a mini-version of the GTR's, only it is much smoother and quieter.

Yes, I agree, much of it is up to the driver. But put 2 equal drivers (one in DCT and one in 6sp manual) and the DCT driver will be faster. You really need to drive one to experience it for yourself. I too had doubts it would be this good.

Just my 2 cents.

Gumpy.

[Boosted_N54]

Originally Posted by gumpy

If you lived close, I would race you. I have about 700 miles on the DCT 135i and let me tell you there is no way possible you can shift as fast as this transmission. The other difference with the N55 vs. N54 (yes I had a 335xi with N54) is it's low end torque. It is so much better down low. Yes the N54 pulled better mid to high rpm, but with the DCT, you can keep it right in the torque band. Also, you can shift gears mid-corner without upsetting the balance of the car. Also, for autocross, you can downshift into 1st without worries of grinding gears in tight hairpins and go back up to 2nd like lightening. I rode with an old tuner friend of mine who had a Nissan GTR and let me tell you this DCT feels like a mini-version of the GTR's, only it is much smoother and quieter.

Yes, I agree, much of it is up to the driver. But put 2 equal drivers (one in DCT and one in 6sp manual) and the DCT driver will be faster. You really need to drive one to experience it for yourself. I too had doubts it would be this good.

Just my 2 cents.

Gumpy.

maybe with 2 equal drivers in a straight line YES your are right .
but when it comes on the highway racing in traffic lane changing in between cars or on twisty roads then its the driver . the reason i say this is because i raced alot of fast cars on twisty roads and in traffic highways and never lost a race and im bone stock and i can only imagine what would happen if i modify my car . and it all comes down to who spends the most $$money$$ to have the fastest 135i.
it dont matter if some 1 has the n54 or the n55 dct what matters is that we ALL have 135i and we are all in this together as a team to show others what we can do with our 135i no 1 dares even to talk shit about our 15i cuz we crazy fast lol

we have a German Supra......................

[egainer]

Originally Posted by Da _Grk_Tuner

maybe with 2 equal drivers in a straight line YES your are right .
but when it comes on the highway racing in traffic lane changing in between cars or on twisty roads then its the driver . the reason i say this is because i raced alot of fast cars on twisty roads and in traffic highways and never lost a race and im bone stock and i can only imagine what would happen if i modify my car . and it all comes down to who spends the most $$money$$ to have the fastest 135i.
it dont matter if some 1 has the n54 or the n55 dct what matters is that we ALL have 135i and we are all in this together as a team to show others what we can do with our 135i no 1 dares even to talk shit about our 15i cuz we crazy fast lol

we have a German Supra......................

wtf? is this a joke? you're saying you're better at highway traffic racing than him? how would you know how he can do in traffic on the highway? you don't.

and now you aren't pushing limits of your car; whoever has fewer brain cells will win that race

[UdubBadger]

[Boosted_N54]

Originally Posted by egainer

wtf? is this a joke? you're saying you're better at highway traffic racing than him? how would you know how he can do in traffic on the highway? you don't.

and now you aren't pushing limits of your car; whoever has fewer brain cells will win that race

i never said that i would beat him i said its a drivers race >
((((maybe with 2 equal drivers in a straight line YES your are right .
but when it comes on the highway racing in traffic lane changing in between cars or on twisty roads then its the driver)))

whats the matter with you

[egainer]

Originally Posted by Da _Grk_Tuner

the reason i say this is because i raced alot of fast cars on twisty roads and in traffic highways and never lost a race and im bone stock and i can only imagine what would happen if i modify my car . and it all comes down to who spends the most $$money$$ to have the fastest 135i.

you said it, not me