BMW M3 Forum
BMW M3 Forum BMW M3 Gallery BMW M3 Reviews BMW M3 Social Groups BMW M3 Chat M3Forum Sponsors >>
Loading


Mobile M3forum
Go Back   BMW M3 Forum.com (E30 M3 | E36 M3 | E46 M3 | E92 M3 | F80/X) > BMW M3 Discussions > E46 M3 (2001-2006)
Tire Rack Buy Winter Tires Now!
Not a member? Register Now!
Register Gallery All Albums Garage Search Today's Posts Mark Forums Read Calendar FAQ

E46 M3 (2001-2006) Engine: S54 - Max Hp: 333 hp at 7,900 rpm / 262 lb/ft at 4,900 rpm
Total Produced: 45,000+ - Years Produced: 2001 to 2006.


Reply
 
Thread Tools Display Modes
Old Fri, Oct-19-2018, 06:51:09 PM   #31
Carbuilder723
Registered User
 
Join Date: Mar 2016
Posts: 82
In the garage:
Reputation: 0 Carbuilder723 is on a distinguished road

United States




Default Re: High compression S54 - Questions abound

I am really starting to lean towards keeping the compression ratio stock at 11.5.
I think as much as it would be really awesome to go full steam ahead on a 12.5 build... I just don't think it's feasible within my budget.
It seems like 12.5 may be worth it in my situation if i was committed to installing 288/280 cams, forged connecting rods, and doing a complete stand alone engine management (AEM Infinity or the like) with flex fuel to compensate (both for fuel and spark) for the times I can't get e85.

Cost aside, sticking with 11.5 is much less complicated, known and flexible given all driving conditions. I'm not building a race car, just a solid sports car, so i am starting to think 12.5 may really be overkill.
__________________
Jump to top Carbuilder723 is online now   Reply With Quote
Sponsored Links
Register now and remove these ads
Old Fri, Oct-19-2018, 07:44:42 PM   #32
ctres
Registered User
 
ctres's Avatar
 
Join Date: Jun 2015
Age: 24
Posts: 462
Reputation: 0 ctres is on a distinguished road
Location: Detroit Metro

United States




Default Re: High compression S54 - Questions abound

Quote:
Originally Posted by Drewster View Post
Also, FWIW, turbo engines with higher boost and lower static CR often have lower peak cylinder pressures than NA engines with high static CR. If you were to look at a PV diagram, a turbo essentially gives you more area under the curve without necessarily raising the peak pressure. The largest downside is that hardly anyone turbocharges this engine, and I imagine those that do have to deal with jeers from purists on a daily basis
You can certainly calibrate a turbocharged engine to make less peak pressure than an NA engine by retarding spark excessively, but in my experience calibrating instrumented engines with cylinder pressure transducers, boosted engines will almost always have a higher peak cylinder pressure when calibrated to the knock threshold, but the peak will be later in the cycle. Retarding spark past the knock threshold to reduce peak cylinder pressure has other consequences as well. Phasing the combustion later causes much higher EGTs, potentially damaging the turbo (something the aftermarket never talks about), not to mention you will have horrendous BSFC.

It's true that a turbo engine will give you more area under the power part of the curve, but there is typically an increase in peak pressure as well. Most NA engines will not get over 100 Bar peak pressure, whereas turbocharged DI engines can generally hit 120 to 125 Bar no problem.
Jump to top ctres is offline   Reply With Quote
Old Fri, Oct-19-2018, 08:53:52 PM   #33
Carbuilder723
Registered User
 
Join Date: Mar 2016
Posts: 82
In the garage:
Reputation: 0 Carbuilder723 is on a distinguished road

United States




Default Re: High compression S54 - Questions abound

Quote:
Originally Posted by ctres View Post
You can certainly calibrate a turbocharged engine to make less peak pressure than an NA engine by retarding spark excessively, but in my experience calibrating instrumented engines with cylinder pressure transducers, boosted engines will almost always have a higher peak cylinder pressure when calibrated to the knock threshold, but the peak will be later in the cycle. Retarding spark past the knock threshold to reduce peak cylinder pressure has other consequences as well. Phasing the combustion later causes much higher EGTs, potentially damaging the turbo (something the aftermarket never talks about), not to mention you will have horrendous BSFC.

It's true that a turbo engine will give you more area under the power part of the curve, but there is typically an increase in peak pressure as well. Most NA engines will not get over 100 Bar peak pressure, whereas turbocharged DI engines can generally hit 120 to 125 Bar no problem.
Alright... It says you live in Detroit metro and you're way too knowledgeable not to work for an OEM. Now I'm curious which one...

Sent from my Pixel 2 XL using Tapatalk
__________________
Jump to top Carbuilder723 is online now   Reply With Quote
Old Fri, Oct-19-2018, 09:00:38 PM   #34
ctres
Registered User
 
ctres's Avatar
 
Join Date: Jun 2015
Age: 24
Posts: 462
Reputation: 0 ctres is on a distinguished road
Location: Detroit Metro

United States




Default Re: High compression S54 - Questions abound

Quote:
Originally Posted by Carbuilder723 View Post
Alright... It says you live in Detroit metro and you're way too knowledgeable not to work for an OEM. Now I'm curious which one...

Sent from my Pixel 2 XL using Tapatalk
I'd rather not say. I don't speak on behalf of my employer, just sharing my experience where it may be of use. Suffice it to say that I have firsthand experience. For the record there are many non OEM engineering consulting companies in the area with some very smart engineers that work on OEM projects.
Jump to top ctres is offline   Reply With Quote
Old Sat, Oct-20-2018, 01:03:28 AM   #35
Cronenberged
Registered User
 
Cronenberged's Avatar
 
Join Date: Nov 2011
Posts: 664
In the garage:
Reputation: 0 Cronenberged is on a distinguished road
Location: East

United States




Default Re: High compression S54 - Questions abound

I would have to dig through the forum but someone did a 3.5L stroker with a 12.1 comp.
__________________
Formerly known as ///M3_Letty

Last edited by Cronenberged; Sat, Oct-20-2018 at 01:06:57 AM.
Jump to top Cronenberged is online now   Reply With Quote
Old Sat, Oct-20-2018, 01:33:43 AM   #36
benzthis
Registered User
 
benzthis's Avatar
 
Join Date: Jan 2007
Posts: 870
Reputation: 0 benzthis is on a distinguished road
Location: queens

United States




Default Re: High compression S54 - Questions abound

I think mister m did a crazy stroker.
__________________
Jump to top benzthis is online now   Reply With Quote
Old Sun, Oct-21-2018, 01:01:37 AM   #37
mpwr92
Registered User
 
Join Date: Sep 2013
Posts: 57
Reputation: 0 mpwr92 is on a distinguished road

United States




Default Re: High compression S54 - Questions abound

Go 12.5.1 288/280 stock lift cams and box u won’t regret it just get paul to tune it.
Running pump fuel data logs with no knock reduction and temps In Australia are starting to get hot! Compression won’t give u much more power but will give you torque.
Jump to top mpwr92 is online now   Reply With Quote
Old Sun, Oct-21-2018, 01:02:10 AM   #38
mpwr92
Registered User
 
Join Date: Sep 2013
Posts: 57
Reputation: 0 mpwr92 is on a distinguished road

United States




Default Re: High compression S54 - Questions abound

If ur gonna buy pistons go JE and Molnar rods
Jump to top mpwr92 is online now   Reply With Quote
Old Sun, Oct-21-2018, 06:35:51 AM   #39
HassanEido
Registered User
 
HassanEido's Avatar
 
Join Date: Oct 2014
Posts: 3,327
In the garage:
Reputation: 0 HassanEido is on a distinguished road

Lebanon




Default Re: High compression S54 - Questions abound

Quote:
Originally Posted by mpwr92 View Post
Go 12.5.1 288/280 stock lift cams and box u won’t regret it just get paul to tune it.
Running pump fuel data logs with no knock reduction and temps In Australia are starting to get hot! Compression won’t give u much more power but will give you torque.
How much did ur car make,translated to US dynojet if possible
__________________

Mods:
-Custom CF airbox
-SSV2 catless headers, Custom 2.5" dual sec1, Custom sec2 2.5" dual with e9xM X pipe, SuperSprint Race inspired custom section 3..
-Cat Cams 280 272.
-Custom dyno tune
-Tms pulleys and electric fan conversion
364.1 whp 287.8 wtq

Custom exhaust thread and dyno http://m3forum.net/m3forum/showthread.php?t=569086
Cams thread and dyno http://m3forum.net/m3forum/showthread.php?t=554439
Custom cf airbox thread http://m3forum.net/m3forum/showthread.php?t=595180
Why not to use after market bearings with surfacetreatments and /or increased clearance
http://www.m3forum.net/m3forum/showp...4&postcount=10
Jump to top HassanEido is offline   Reply With Quote
Old Sun, Oct-21-2018, 09:19:20 AM   #40
mpwr92
Registered User
 
Join Date: Sep 2013
Posts: 57
Reputation: 0 mpwr92 is on a distinguished road

United States




Default Re: High compression S54 - Questions abound

Still running in so haven’t had it on the dyno will be tuned before Christmas but feels very diffrent to before with same setup stock
Bottom end. Built a fair few
S54’s in my life.
Jump to top mpwr92 is online now   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

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. The time now is 04:25:35 AM.


Powered by vBulletin® Version 3.8.6
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.
M3Forum.com and M3forum.net is in no way sponsored, endorsed or affiliated by or with BMW NA / BMW AG or any of it's subsidiaries or vendors.
BMW and M3 (E90 M3 | E92 M3 | E93 M3 | E46 M3 | E36 M3 | E30 M3) are registered trademarks of BMW AG.
M3Forum Terms of Service
Copyright ©1999-2017 M3Forum.com
Discussing High compression S54 - Questions abound in the E46 M3 (2001-2006) Forum - Engine: S54 - Max Hp: 333 hp at 7,900 rpm / 262 lb/ft at 4,900 rpm
Total Produced: 45,000+ - Years Produced: 2001 to 2006. at BMW M3 Forum.com (E30 M3 | E36 M3 | E46 M3 | E92 M3 | F80/X)