PCM Diagnostics & Tuning HP Tuners | Holley | Diablo
Sponsored by:
Sponsored by:

O2 reading question...

Thread Tools
 
Search this Thread
 
Old 03-08-2004, 10:03 AM
  #1  
Stu
TECH Resident
Thread Starter
 
Stu's Avatar
 
Join Date: Jan 2002
Location: In front of my computer
Posts: 922
Likes: 0
Received 0 Likes on 0 Posts

Default O2 reading question...

What are alot of you LS1 guys seein for the O2 readings? I know its not a accurate way to tune. I cant afford a wideband dyno session right now.

I am getting about 24 degrees total timing and about 1-2 degrees KR. O2s read around .860 at WOT in 3rd gear. Id like to see at least 26 degrees total and no knock.

.860 seems a little lean to me. My PE vs RPM is set at 1.2655 from 4000 RPM up.

Any suggestions?

Stu
Old 03-08-2004, 10:25 AM
  #2  
Moderator
iTrader: (11)
 
jimmyblue's Avatar
 
Join Date: Mar 2002
Location: East Central Florida
Posts: 12,605
Likes: 0
Received 6 Likes on 6 Posts

Default

Stock manifold car, I see right about 900mV
unless I fatten it up. Predator tune appears
to add 20mV to WOT O2s by my logs (900mV
stock tune goes to 920mV w/ their "canned"
program). Predator adds about 6 degrees
advance (my 24 goes to 30 w/ Pred at 6KRPM).
My MAF is not stock but is tweaked in for good
LTFTs.
Attached Thumbnails O2 reading question...-stock_vs_predator.gif  
Old 03-08-2004, 05:58 PM
  #3  
LS1Tech Administrator
iTrader: (3)
 
RPM WS6's Avatar
 
Join Date: Nov 2001
Location: Schiller Park, IL Member: #317
Posts: 32,033
Likes: 0
Received 1,483 Likes on 1,067 Posts

Default

Originally Posted by Stu
What are alot of you LS1 guys seein for the O2 readings? I know its not a accurate way to tune. I cant afford a wideband dyno session right now.

I am getting about 24 degrees total timing and about 1-2 degrees KR. O2s read around .860 at WOT in 3rd gear. Id like to see at least 26 degrees total and no knock.

.860 seems a little lean to me. My PE vs RPM is set at 1.2655 from 4000 RPM up.

Any suggestions?

Stu
.860 is pretty lean.

I'm at .89x at peak rpms with 27.5* timing and no KR. I've set my PE vs RPM at 1.19 across the whole board. But's that's with my IFR table scaled at 90% of stock for the whole table.

Is your IFR table stock?

What are your LTFTs?

Is your MAF table (and the MAF itself) stock?
Old 03-08-2004, 06:55 PM
  #4  
Stu
TECH Resident
Thread Starter
 
Stu's Avatar
 
Join Date: Jan 2002
Location: In front of my computer
Posts: 922
Likes: 0
Received 0 Likes on 0 Posts

Default

Yeah, the MAF is stock. Down to the screen. I did have to adjust my IFR to 97% to get the cruising LTrims right. I played with it a little more today and took my PEvsRPM table up to 1.29 and my O2s went to .890 and my timing stayed at 26 across the board. I'll play with the timing more tomorrow if the weather holds. Thanks guys.



Stu
Old 03-08-2004, 07:28 PM
  #5  
LS1Tech Administrator
iTrader: (3)
 
RPM WS6's Avatar
 
Join Date: Nov 2001
Location: Schiller Park, IL Member: #317
Posts: 32,033
Likes: 0
Received 1,483 Likes on 1,067 Posts

Default

Originally Posted by Stu
Yeah, the MAF is stock. Down to the screen. I did have to adjust my IFR to 97% to get the cruising LTrims right. I played with it a little more today and took my PEvsRPM table up to 1.29 and my O2s went to .890 and my timing stayed at 26 across the board. I'll play with the timing more tomorrow if the weather holds. Thanks guys.



Stu
I'm surprised that you would need a 1.29 PE multiplier for such a good O2 (.890). Espeically since you've decreased your IFR table. Even with my 1.19 PE number, I still only get a .898mv O2 reading. That's with the IFR table at 90% of stock and the LTFTs at 0 during WOT.
Old 03-08-2004, 09:36 PM
  #6  
TECH Senior Member
iTrader: (33)
 
WS6FirebirdTA00's Avatar
 
Join Date: Mar 2003
Location: North Carolina
Posts: 8,318
Likes: 0
Received 1 Like on 1 Post

Default

mine was good at about 905mV, its hard to get with stock o2s but just gotta find what works for you, get where u have no knokck and get 10 more mV out of it, thast how i did it
Old 03-08-2004, 09:52 PM
  #7  
LS1Tech Administrator
iTrader: (3)
 
RPM WS6's Avatar
 
Join Date: Nov 2001
Location: Schiller Park, IL Member: #317
Posts: 32,033
Likes: 0
Received 1,483 Likes on 1,067 Posts

Default

Originally Posted by WS6FirebirdTA00
mine was good at about 905mV, its hard to get with stock o2s but just gotta find what works for you, get where u have no knokck and get 10 more mV out of it, thast how i did it
Yep, I was able to get down to .890mv with a 1.17 PE multiplier without KR (27.5* max timing), but I upped it 1% to 1.19 just incase the warmer summer IAT needs a little more fuel for cooling. The 1% bump took me up to .898mv, or a .008mv increase (richer)......




All times are GMT -5. The time now is 10:19 AM.