Jump to content

4d fuel negative value


rmn
 Share

Recommended Posts

Hello
Just curious is 4d fuel corection negative numbers normal or not?
We have rb3.4/rb26 with id1700x injectors (dead time and short pulse adder taken from id site).
TPS table tuned to 0.8>0.6 bar spring pressure. Once I add boost it running richer then my target.Had to remove -15% of fuel at 1.2 1.6 bar.
Before 1700 injectors, there was 1000 bosch or denso and 4d fuel corections were positive.
Thank you.
set up:
bnr 34
3.4 /rb26
tomei 280 11.6 
dual walbros 450lph on modified fuel lines (10an)
efr9174


cal and log attached
 

2018_id1700x_1.4.pclr

1.4.llg

Link to comment
Share on other sites

Yes it is normal to have -ve numbers in the 4D table with this type of strategy, far less common to have positive numbers.  As you increase boost, turbine back pressure increases so VE reduces therefore you need less fuel. 

Was the only change injectors, or has there been some other change compared to the previous tune? 

Link to comment
Share on other sites

26 minutes ago, Adamw said:

Was the only change injectors, or has there been some other change compared to the previous tune? 

 

Injectors and dual intank walbro instead 2000cc bosch injectors (cheap ones, for lpg) and dual bosch044 which was intalled in trunk and sucked fuel.
1000cc was last year and doesnot meet power goals.
Any suggestions are welcome .
Thank you.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
 Share

×
×
  • Create New...