1st SETUP injectors (flowrate, rate modifier, Min pulse width, PW adder) - Page 2 - Cobalt SS Network

Go Back  Cobalt SS Network > Engine Technical Discussion > Tuning
1st SETUP injectors (flowrate, rate modifier, Min pulse width, PW adder) >

1st SETUP injectors (flowrate, rate modifier, Min pulse width, PW adder)

Tuning For tuning and related discussions

1st SETUP injectors (flowrate, rate modifier, Min pulse width, PW adder)

Old 10-12-2007, 09:05 AM
  #26  
Senior Member
 
SJSchafer's Avatar
 
Join Date: 05-02-07
Location: San Jose, CA
Posts: 1,061
Thanks: 0
Thanked 0 Times in 0 Posts
Originally Posted by Witt View Post
That number is too high to run at idle. The amount of fuel needed to sustain 15-1 a/f at idle on our mouse motors is less than 1.0ms which is why you are showing a rich condition.

Set the min. pulse wdith to about half that and use the short pulse adder table to add pulse width to values below 1.0ms in a progressive fashion. (something like .1ms at 1.0, then 12.5% less at every value below that until you hit 0 which your adder would also be 0.....the interpolate function is good for this).<----Just an example, don't quote me on those numbers. Basically you have to play around with the short pulse adder table and find the rates that allow a smooth idle and smooth sweeping air-fuel gauge. Jacking up the idle a little is another easy fix and will become almost necessary as you increase the pipe diameter the o2 is housed in as o2 switching speed becomes an issue at idle.

I think the advertised min. pulse width for 650cc injectors is like 1.1ms at 100kpa (atmospheric) so at lower pressure it will obviously also be a lower possible pulse width.

That's basically what I am doing, but tuning the adders is a major PITA.
SJSchafer is offline  
Old 10-12-2007, 10:44 AM
  #27  
Doc
Senior Member
 
Doc's Avatar
 
Join Date: 11-11-05
Location: Oceanside, Ca
Posts: 9,438
Thanks: 0
Thanked 0 Times in 0 Posts
tell me about it, I just changed my tune and it runs great...
I have had a few times where it cuts out on me and the rpms fluxuate right before....I'm stumped..
Doc is offline  
Old 10-12-2007, 11:49 AM
  #28  
Senior Member
 
SJSchafer's Avatar
 
Join Date: 05-02-07
Location: San Jose, CA
Posts: 1,061
Thanks: 0
Thanked 0 Times in 0 Posts
This is what my adder table is looking like now:

0 0.125 0.25 0.375 0.5 0.625 0.75 0.875 1 1.125 1.25 1.375 1.5 1.625 1.75
0.85938 0.73438 0.61719 0.5 0.39844 0.27344 0.16406 0.13281 0.11719 0.04688 0.02344 0.00781 0.00781 0.00781 0.00781
0.85938 0.85938 0.86719 0.875 0.89844 0.89844 0.91406 1.00781 1.11719 1.17188 1.27344 1.38281 1.50781 1.63281 1.75781

The top line, is the adder cell. The next is the adder value. The third is the total of the 2, which is how I know which cell to change. I have a few histos that I created to let me know what the actual PW is when getting errors. The example above is a recent, "start over again" table, so it still has some errors, but all in all I think I am on the right track.
SJSchafer is offline  
Old 10-12-2007, 12:00 PM
  #29  
Rent me! per hour
 
Area47's Avatar
 
Join Date: 03-22-07
Location: Still fixing others mistakes.
Posts: 24,186
Thanks: 0
Thanked 19 Times in 13 Posts
Originally Posted by Doc View Post
tell me about it, I just changed my tune and it runs great...
I have had a few times where it cuts out on me and the rpms fluxuate right before....I'm stumped..
yepo. mine does this at random times. never at wot though. i have so many freaking 60lb maps laying around its not even funny.
Area47 is offline  
Old 11-01-2007, 03:06 AM
  #30  
Senior Member
 
M88ArRamadi's Avatar
 
Join Date: 04-24-06
Location: Chester, VA
Posts: 1,948
Thanks: 0
Thanked 0 Times in 0 Posts
Questions:

When I'm tuning in VE....my idle is jacked!! Spark jumps from 5 - 12 and fuel sweeps from 13.2 - 16.0 . It seems like no matter what I do....it still does it. If I'm tuning MAF WB sweeps like 14.4-15.0 and timing is fine....nice smooth idle. How do i fix this idle in VE?

Kennyspec: you said "set PE Enable MAP to 115kpa ~ 3 psi"

115 KPA is 16.68 PSI....did you mean 15 kpa?
M88ArRamadi is offline  
Old 11-01-2007, 09:26 AM
  #31  
Senior Member
 
SJSchafer's Avatar
 
Join Date: 05-02-07
Location: San Jose, CA
Posts: 1,061
Thanks: 0
Thanked 0 Times in 0 Posts
VE is more sensitive to other errors. Sounds like an adder issue, but I would need to see your tune and log. As for kPa, you are using the wrong conversion. Yes, 115 kPa is 16.5 psi, but barametric pressure is 14.5 psi. That means that 100 kPa (14.5 psi) is 0 psi of boost. 115 kPa is about 2 psi boost (or so). (115-100)*0.14504 = 2.1756 psi of boost.
SJSchafer is offline  
Old 11-01-2007, 12:08 PM
  #32  
Senior Member
 
M88ArRamadi's Avatar
 
Join Date: 04-24-06
Location: Chester, VA
Posts: 1,948
Thanks: 0
Thanked 0 Times in 0 Posts
makes sense...thanks
M88ArRamadi is offline  
Old 02-29-2008, 10:35 AM
  #33  
Senior Member
iTrader: (3)
 
Join Date: 04-02-06
Location: Harrisburg, PA
Posts: 4,513
Thanks: 0
Thanked 0 Times in 0 Posts
so if im running 60lb injectors whats the short pulse and min pw supposed to be?
Rodimus_Prime is offline  
Old 02-29-2008, 11:39 AM
  #34  
Senior Member
 
SJSchafer's Avatar
 
Join Date: 05-02-07
Location: San Jose, CA
Posts: 1,061
Thanks: 0
Thanked 0 Times in 0 Posts
Originally Posted by Rodimus_Prime View Post
so if im running 60lb injectors whats the short pulse and min pw supposed to be?
The short pulse limit tells the ECM when to look to the adder table, so set that to where your adders start. For instance, if you set your adder table to start ramping PW from 1.125ms to 0ms, set your short pulse limit to 1.125ms. The min PW isn't really that big a deal, since if your adders are set up properly, you will see a min PW of whatever your adders says. I have mine set to .102ms but because of my adder tables I never see less than .6ms or so.
SJSchafer is offline  
Old 05-29-2008, 07:38 PM
  #35  
Senior Member
 
Join Date: 08-28-07
Location: columbus
Posts: 755
Thanks: 0
Thanked 0 Times in 0 Posts
I just bought hptuners and am very new to tunning. my first question is how do you cal. your g/sec and come up with a flow rate for 42.5lb injectors? is the fuel psi at wot or part throttle? sorry if I come off as a noob.
boostking is offline  
Old 11-12-2008, 08:24 PM
  #36  
Senior Member
iTrader: (1)
 
Join Date: 06-27-05
Location: Wilson, NY
Posts: 1,397
Thanks: 0
Thanked 0 Times in 0 Posts
I have kind of dumb question. How does the VCM detect and enable COT protection, when the car doesn't have a temp sensor in the cat?
BeermanSSSC is offline  
Old 02-04-2009, 12:24 AM
  #37  
Banned
 
Join Date: 10-14-07
Location: Austin, TX
Posts: 1,546
Thanks: 0
Thanked 0 Times in 0 Posts
Originally Posted by SJSchafer View Post
I have actually heard a bit of conflicting info on these injectors as to lbs/hr, but the 630 cc/min were all the same, so I did some math based on those. Seimen calls their injectors 60#, but if you take:

cc/min x .103 = lbs/hr then
630 x .103 = 64.89
Sorry for necroing this thread, but I'm going to start tuning my car soon and this information is really handy. Figured I'd bump it for anyone else who was interested.

Using SJSchafer's old formula of cc/min * .103 = lbs/hr, my flowmatched 60# injectors were calculated as 71.4 lbs/hr, which seemed really odd. I did a quick google and found on other forums that the proper formula is actually cc/min / 10.5 = lbs/hr, giving me the much more reasonable 66.1 (which also matches the numbers provided from the flowmatching company), and doing 630/10.5, gives you exactly 60.

Just on the off chance someone was using that formula to calculate the flowrates, I figured this could help.

Also, this spreadsheet is awesome and is the one everyone in the thread keeps referencing.
http://www.thetuningdoctor.com/Excel...orscalels2.xls
Dainslaif is offline  
Old 03-09-2009, 05:12 PM
  #38  
Senior Member
 
Join Date: 11-12-07
Location: Maryland
Posts: 1,537
Thanks: 0
Thanked 0 Times in 0 Posts
subd
Jrhdpaintball is offline  
Old 03-09-2009, 11:54 PM
  #39  
Senior Member
 
Join Date: 11-12-07
Location: Maryland
Posts: 1,537
Thanks: 0
Thanked 0 Times in 0 Posts
ok question just so i think i understand something...

EQ Ratio Vs.RPM table is

1.300 across the board... which is calculated by 14.7/11.3=1.300 i figured 11.3 would be safe to start..

at WOT im getting around 10.3 or so... would i need to command something higher than 11.3 to get WOT afr correct... or is there something in my ifr tables or adders?

short pulse 2.000

adder is 0.00 across the board

any help would be awsome thanks... just learning all this...

also my idle flucuates most of the time after coming to a stop... and afr jumps

Last edited by Jrhdpaintball; 03-09-2009 at 11:54 PM. Reason: Automerged Doublepost
Jrhdpaintball is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Sl0wbaltSS
2.0L LNF Performance Tech
18
11-21-2018 11:11 PM
taintedred07
2.0L LNF Performance Tech
31
04-24-2016 12:10 PM
Zharrington_2010LNF
2.0L LNF Performance Tech
21
02-08-2016 01:43 PM
dennis69
Appearance
9
10-20-2015 04:49 PM
patooyee
2.4L LE5 Performance Tech
50
10-15-2015 05:11 PM


Thread Tools
Search this Thread
Quick Reply: 1st SETUP injectors (flowrate, rate modifier, Min pulse width, PW adder)


Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.