It is currently Thu Dec 13, 2018 1:54 pm



Post new topic Reply to topic  [ 16 posts ]  Go to page Previous  1, 2
Author Message
 Post subject: Re: Closed loop lambda problem
PostPosted: Tue Jul 10, 2018 3:52 pm 
Offline

Joined: Mon Jan 16, 2012 1:39 pm
Posts: 80
ECU Model: S40 Pro
Firmware Version: 58
awesome info Alex, didnt know that different injector drivers will have different dead times....


Top
 Profile  
 
 Post subject: Re: Closed loop lambda problem
PostPosted: Tue Jul 10, 2018 4:11 pm 
Offline

Joined: Mon Jan 16, 2012 1:39 pm
Posts: 80
ECU Model: S40 Pro
Firmware Version: 58
ID Injectors dead times

https://www.hamotorsports.com/injector- ... rates.html


Injector dead times, offsets, flow rates, and slopes for ID injectors. Note that all charts are rated at FUEL PRESSURE DIFFERENTIAL across the injector, not simply rail pressure.


Top
 Profile  
 
 Post subject: Re: Closed loop lambda problem
PostPosted: Tue Jul 10, 2018 4:40 pm 
Offline

Joined: Tue Aug 02, 2011 12:08 pm
Posts: 2913
Location: Norn Iron
ECU Model: No ECU
iceman_n wrote:
ID Injectors dead times

https://www.hamotorsports.com/injector- ... rates.html


Injector dead times, offsets, flow rates, and slopes for ID injectors. Note that all charts are rated at FUEL PRESSURE DIFFERENTIAL across the injector, not simply rail pressure.


But if the FPR and fuel system is working correctly...your injector should always be seeing a single pressure differential across it.


Top
 Profile  
 
 Post subject: Re: Closed loop lambda problem
PostPosted: Tue Jul 10, 2018 6:32 pm 
Offline

Joined: Mon Jan 16, 2012 1:39 pm
Posts: 80
ECU Model: S40 Pro
Firmware Version: 58
When an engine is idling, there is a vacuum in the intake manifold. This vacuum pulls fuel out of the injectors, and increases the effective pressure across the injector to a pressure higher than the rail pressure itself.

When a supercharged or turbocharged vehicle is in boost, the pressure inside the manifold is trying to push fuel back into injector, resisting the flow and decreases the effective fuel pressure below that of the rail.


Top
 Profile  
 
 Post subject: Re: Closed loop lambda problem
PostPosted: Wed Jul 11, 2018 5:58 am 
Offline

Joined: Tue Aug 02, 2011 12:08 pm
Posts: 2913
Location: Norn Iron
ECU Model: No ECU
iceman_n wrote:
When an engine is idling, there is a vacuum in the intake manifold. This vacuum pulls fuel out of the injectors, and increases the effective pressure across the injector to a pressure higher than the rail pressure itself.

When a supercharged or turbocharged vehicle is in boost, the pressure inside the manifold is trying to push fuel back into injector, resisting the flow and decreases the effective fuel pressure below that of the rail.



Which is why it is commonplace to run a referenced FPR. So there is always a constant pressure delta across the injector.

So neither boost or intake vac will alter what is happening at the injector.


Top
 Profile  
 
 Post subject: Re: Closed loop lambda problem
PostPosted: Wed Jul 11, 2018 12:56 pm 
Offline

Joined: Sun Jan 27, 2013 6:08 pm
Posts: 264
ECU Model: S60 Pro
Firmware Version: 29
Or you create the fuel MAP without a referenced FPR with lower values due to vac. and add compensations based of the MAP sensor to enrich under boost - all quite simple and effective!


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 16 posts ]  Go to page Previous  1, 2

Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Theme designed by stylerbb.net © 2008
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group
All times are UTC - 5 hours