[scheherazade]

The "rule of thumb" is :

twin turbo = more down low
single turbo = more up top


Just a generalization. It's not an actual rule.

-scheherazade

[roozie2001]

either way i think im gonna have to go with the 2012ish M3 TT FTW. i cant wait to see what that beast does.

[Sniz]

I'm enjoying myself going from a twin turbo BMW to a single turbo BMW. A gt35r on a 3.2L s52 really doesnt have that much lag at all assuming you know how to drive. If your below 3000rpms......downshift. It spools very quick and hits so much harder than the little twins on the n54 could even dream of.

[Former_Boosted_IS]

Originally Posted by joec500

The Twin Scroll Technology has been around for some time, in P-cars 997 TT.

I am really excited to see how this new powerplant pans out. It will probably be easier to do turbo servicing and should provide some new fun challenges for tuners!

Ah, my bad here guys. I misinterpretted the Twin Scroll as sequential.

[TurboBimmer]

Originally Posted by Sniz

I'm enjoying myself going from a twin turbo BMW to a single turbo BMW. A gt35r on a 3.2L s52 really doesnt have that much lag at all assuming you know how to drive. If your below 3000rpms......downshift. It spools very quick and hits so much harder than the little twins on the n54 could even dream of.

That's the definition itself of the "turbo hole" (turboloch in german) which engineers have to avoid in modern engines to make the car comfortably drivable in everyday situations. Most customers don't want to drive a car which feels powerless at low rps and then suddenly takes off like a rocket

[Zeph]

the dreaded single turbo lag is more common to 4 cylinder engines really, or people putting huge turbo's on say a supra so they can park it on the dyno and brag about 1000 RWHP.

I6 engines put out alot of exhaust heat and pressure very quickly. They can spool up small to medium turbos really quickly. A GT35 for example will probably hit hard by 3k rpm's and if you are in a manual you should never be below 3k unless you are in 1st gear (in a racing situation). You really don't need it in 1st because you will just sit and spin, plus 1st revs up so fast you won't have time to notice the lag. Basically don't go for a ride in a SRT-4 with an upgraded (bigger) single and then think a 335i with a single is going to feel the same...

[ShortCkT101]

I would take the single turbo, any day over twin. I bet with single turbo when you hit 4th gear you won't stop pulling. Unlike the N54 you can feel that the little snails are running out of air. Also after jb3 for the N55 comes out, I bet you will see higher # then the N54.

[ar design]

Originally Posted by Weaselboy

Bub Rub... is that you?

[OpenFlash]

Originally Posted by scheherazade

The "rule of thumb" is :

twin turbo = more down low
single turbo = more up top


Just a generalization. It's not an actual rule.

-scheherazade

In this case, the N55 will offer more low end torque and less lag due to its twin scroll design and the implementation of Valvtronic. But it wont likely have the same max power potential as the N54. So in may ways, it wont be the desirable engine to have if you want to tune your 3 series. For that, the N54 will probably always be king. The N54 is practically a 400hp engine detuned to make 300hp. We wont be so lucky with the N55.

Shiv

[cn555ic]

Originally Posted by shiv@vishnu

In this case, the N55 will offer more low end torque and less lag due to its twin scroll design and the implementation of Valvtronic. But it wont likely have the same max power potential as the N54. So in may ways, it wont be the desirable engine to have if you want to tune your 3 series. For that, the N54 will probably always be king. The N54 is practically a 400hp engine detuned to make 300hp. We wont be so lucky with the N55.

Shiv

WOW!

[vase330]

Originally Posted by shiv@vishnu

In this case, the N55 will offer more low end torque and less lag due to its twin scroll design and the implementation of Valvtronic. But it wont likely have the same max power potential as the N54. So in may ways, it wont be the desirable engine to have if you want to tune your 3 series. For that, the N54 will probably always be king. The N54 is practically a 400hp engine detuned to make 300hp. We wont be so lucky with the N55.

Shiv

Dayum, in that case I am keeping my car for 9yrs.

[hotrod182]

Originally Posted by shiv@vishnu

In this case, the N55 will offer more low end torque and less lag due to its twin scroll design and the implementation of Valvtronic. But it wont likely have the same max power potential as the N54. So in may ways, it wont be the desirable engine to have if you want to tune your 3 series. For that, the N54 will probably always be king. The N54 is practically a 400hp engine detuned to make 300hp. We wont be so lucky with the N55.

Shiv

This is correct. With Valvetronic and the twin-scroll, it will be a much harder platform to tune for higher hp. The factory can implement many more roadblocks. Everyone is saying the bigger single is capable of higher rpm airflow. But remember, that bigger single turbo will need to generate twice as much airflow as each one of our twin turbos just to net the SAME result we currently have. Having 2 bigger turbos to replace our twins is one thing, while relying on one turbo to flow twice that same air flow is another thing. Especially a twin scroll which is inherently more restrictive in the upper rpm ranges.

[marconi118]

And don't forget N55 has mass air sensor in it, it will be 10 more difficult to tune it with piggy... only flash if it can tweak the valvetronic.

[cn555ic]

my mind is set..I am keeping my car for another 7 years!

[marcel b]

just read a german test of the 535i GT which has the N55. they where not enthousiastic about it and stated it does not behave as promised by BMW, referring to the promissed less lag. they complained about engine vibrations and relative high fuel consumption.

[stressdoc]

The N55 may be detuned further in the F30 (2012), but a new twin turbo version may be offered in a 340 or supersport model, with 360+ hp. Let's hope Shiv et al can crack the e-barriers that BMW will have in place to deter tuners on that engine.

Audi beware.

[dlbrooks18]

[zibawal]

how abt 335i getting single turbo, come spring face lift

[Alpina_B3_Lux]

Originally Posted by stressdoc

The N55 may be detuned further in the F30 (2012), but a new twin turbo version may be offered in a 340 or supersport model, with 360+ hp. Let's hope Shiv et al can crack the e-barriers that BMW will have in place to deter tuners on that engine.

Audi beware.

Tuners here in Germany got no problem with cracking the newest BMW software, for example on the X6 V8 Biturbo. So I guess that should not be the problem.

Alpina_B3_Lux

[Bluechipper]

Originally Posted by cn555ic

335s are getting this single turbo and the new M3 are getting the twin turbos...I don't see how this single turbo N55 will be made to out perform what we have now or even come close, especially when they have the Ms slated to have twin turbos. IMO I feel the only reason is to detune the 335 and make the M more powerful and attractive since the 3 series M that is out today hasn't faired well against the 335 as for sales...

Nope

There will be a 340i with twin turbos and 360hp.

http://www.carmagazine.co.uk/Secret-...-new-2011-F30/

next M3 will have same power, 414hp, from a twin turbocharged STRAIGHT SIX with direct injection
upgraded dual-clutch gearbox
next 335i loses 1 turbo and power down to 280hp
340i with a twin turbo with 360hp