E90Post
 


N54Tuning.com
 
BMW 3-Series (E90 E92) Forum > E90 / E92 / E93 3-series Powertrain and Drivetrain Discussions > N54 Turbo Engine / Drivetrain / Exhaust Modifications - 335i > PTF UPDATE: 553WHP 631WTQ - N54 TwinTurbo World Record



Reply
 
Thread Tools Search this Thread
      11-27-2012, 04:52 AM   #155
Alpina_B3_Lux
Colonel
Alpina_B3_Lux's Avatar
Germany
63
Rep
2,451
Posts

 
Drives: Audi R8 V10, BMW 330d E91 LCI
Join Date: Feb 2008
Location: Germany

iTrader: (0)

Garage List
2009 335i  [4.39]
Quote:
Originally Posted by bigdnno98 View Post
Just took a look at VACs site. It says they have N54 pistons, I'm not sure anyone has ever used them though. I guess you could say they're an option, just not sure I would want to be first at it.
E92Fan over at the UK section has been running upgraded pistons and rods, both from Pankl Racing / CP-Carrillo. Lower compression ratio (I think identical to the one Alpina uses on their B3 BT), much lighter materials on the pistons and titanium rods. Runs very well, he just doesn't have time to spend on his car right now unfortunately.

Alpina_B3_Lux
__________________
Audi R8 V10; sold: BMW 335i
Appreciate 0
      11-27-2012, 06:52 PM   #156
J Boy
Private
J Boy's Avatar
0
Rep
68
Posts

 
Drives: B6 A4
Join Date: Jun 2012
Location: West Covina

iTrader: (0)

Quote:
Originally Posted by Ænema View Post
I'm just saying that if the octane is there and the tuning is solid then the higher the compression the better the car will perform.
Not sure exactly what you mean by "the better the car will perform." but from what I understand, a lower CR will give turbo cars better peaks and take away from their low end.
__________________
B6 A4
REVO Stage 2

Appreciate 0
      11-27-2012, 06:54 PM   #157
CaptainInsano
First Lieutenant
3
Rep
328
Posts

 
Drives: 2007 E92 335i 6MT
Join Date: May 2011
Location: Peninsula, SF Bay Area

iTrader: (0)

Quote:
Originally Posted by J Boy View Post
Not sure exactly what you mean by "the better the car will perform." but from what I understand, a lower CR will give turbo cars better peaks and take away from their low end.
As long as they can make the boost. Lower compression allows you to run more boost (correct me if I'm wrong).
__________________
FFTEC 6466 6mt 335i | FFTEC GTX3076R Evo IX
Appreciate 0
      11-27-2012, 06:59 PM   #158
J Boy
Private
J Boy's Avatar
0
Rep
68
Posts

 
Drives: B6 A4
Join Date: Jun 2012
Location: West Covina

iTrader: (0)

I love this thread however, and it's also very interesting to read all the mixed reviews. Personally to those who are bashing on the RB turbos because of their less peak output than the singles, you have to remember these turbos are simply a direct swap turbo meant to be utilized with stock manifolds and housings. Of course a single will have a higher peak number but that isn't what the point here is...

Mad respect for OP and progress, not to mention the tune isn't finalized yet. The only concern I have is with the head, I would assume that the better flowing head would be giving the car a better top end? Also I thought the car would be able to keep revving past redline a bit with that head?

Like to see more results and progress though
__________________
B6 A4
REVO Stage 2

Appreciate 0
      11-27-2012, 10:30 PM   #159
Sniz
Lieutenant General
Sniz's Avatar
190
Rep
10,572
Posts

 
Drives: e92 335 - gone // e36 M3 turbo
Join Date: Mar 2007
Location: Ellicott City, MD

iTrader: (1)

some big power guys!
__________________
Appreciate 0
      11-27-2012, 11:57 PM   #160
Ænema
Captain
10
Rep
961
Posts

 
Drives: BMW
Join Date: Aug 2012
Location: Arizona Bay

iTrader: (0)

Quote:
Originally Posted by J Boy View Post
Not sure exactly what you mean by "the better the car will perform." but from what I understand, a lower CR will give turbo cars better peaks and take away from their low end.
In a perfect world(no limit on octane) the higher the compression ratio the more power the engine will make. Period.

However, with pump gas you run into an issue of the high compression ratio making the engine very likely to pre-ignite and detonate. So you take some CR out to make the engine less likely to knock.
__________________
"I'm not surprised you get along well with all the other neighbours. If you put fifty children with Down's syndrome in a room there is going to be a lot of hugging." David Thorne
Appreciate 0
      11-28-2012, 02:57 AM   #161
J Boy
Private
J Boy's Avatar
0
Rep
68
Posts

 
Drives: B6 A4
Join Date: Jun 2012
Location: West Covina

iTrader: (0)

Quote:
Originally Posted by Ænema View Post
In a perfect world(no limit on octane) the higher the compression ratio the more power the engine will make. Period.

However, with pump gas you run into an issue of the high compression ratio making the engine very likely to pre-ignite and detonate. So you take some CR out to make the engine less likely to knock.
Makes sense. The reason I said that was because when going through a lot of different threads on other platforms people tend to run lower compression when making big boost however, when using big turbos, they typically don't build boost until later in the powerband. So with the lower compression ratios, they are losing a lot of their low end - mid range since they are making minimal boost.

Looking at the powerband of the RB turbos, they seem to be a very quick turbo and don't build large amounts of boost so I can definitely see where you are coming from.
__________________
B6 A4
REVO Stage 2

Appreciate 0
      11-28-2012, 03:15 AM   #162
A4rings
First Lieutenant
6
Rep
354
Posts

 
Drives: 07 Space 335i
Join Date: Jan 2010
Location: SBizzle

iTrader: (0)

Quote:
Originally Posted by J Boy View Post
Not sure exactly what you mean by "the better the car will perform." but from what I understand, a lower CR will give turbo cars better peaks and take away from their low end.
Lower compression ratio allows for more boost.
Appreciate 0
      11-28-2012, 03:27 AM   #163
J Boy
Private
J Boy's Avatar
0
Rep
68
Posts

 
Drives: B6 A4
Join Date: Jun 2012
Location: West Covina

iTrader: (0)

Quote:
Originally Posted by A4rings View Post
Lower compression ratio allows for more boost.
Yeeeeesssssssssssssssssssssssssssssssss
__________________
B6 A4
REVO Stage 2

Appreciate 0
      11-28-2012, 08:03 AM   #164
Sigma 3
First Lieutenant
5
Rep
338
Posts

 
Drives: A few things
Join Date: Jun 2009
Location: Tri cities

iTrader: (1)

Take a look at some of the builds on boosted e 46 M3 s . They are raising the compression as well. More boost does not always equal more power.
__________________
In the land of the blind the man with one eye is King
Appreciate 0
      11-28-2012, 09:48 AM   #165
Joshboody
Lieutenant Colonel
25
Rep
1,708
Posts

 
Drives: pickemuptruck
Join Date: Jul 2009
Location: Phoenix, AZ

iTrader: (7)

Air density is always more powerful then mechanical advantage, BUT both is even better. The CR limits are because of knock, but DI allows higher CR (less knock) so you really can't compare to PI.
Appreciate 0
      11-28-2012, 12:21 PM   #166
Ænema
Captain
10
Rep
961
Posts

 
Drives: BMW
Join Date: Aug 2012
Location: Arizona Bay

iTrader: (0)

Quote:
Originally Posted by Joshboody View Post
Air density is always more powerful then mechanical advantage, BUT both is even better. The CR limits are because of knock, but DI allows higher CR (less knock) so you really can't compare to PI.
Yep, the thing to keep in mind is that CR will always be there regardless of RPM(I know, I know dynamic CR changes a little based on numerous factors but this basically holds true.) So that means you can help to offset poor off-boost performance by running a healthy CR. It also increases fuel mileage.
__________________
"I'm not surprised you get along well with all the other neighbours. If you put fifty children with Down's syndrome in a room there is going to be a lot of hugging." David Thorne
Appreciate 0
Reply

Bookmarks

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -5. The time now is 05:36 AM.




e90post
Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
1Addicts.com, BIMMERPOST.com, E90Post.com, F30Post.com, M3Post.com, ZPost.com, 5Post.com, 6Post.com, 7Post.com, XBimmers.com logo and trademark are properties of BIMMERPOST