just when I thought I was close to done...
12-20-2005, 07:54 PM
#1
12 Second Club
Thread Starter
iTrader: (13)
Join Date: Nov 2001
Location: San Diego, CA
Posts: 1,898
Likes: 0
Received 0 Likes
on
0 Posts
just when I thought I was close to done... As our saga left off, I had finished up my MAF and the car was running pretty good in open loop with the MAF on, AFR error % -2 to -8 across the board (which was where the car had the best throttle reponse).
I put the new RAF, VE, OLFA, PE and MAF tables into my original tune yesterday, with MAF and fuel trimming (basically everything) back on. Drove today to work and back logging.
The AFR is about a point leaner than commanded at WOT (which I guess I can adjust PE more rich, but is it OK to tell it whatever it takes to achieve the desired AFR on the wideband ?). I'm commanding 11.2 and it's in the mid 12's which is too lean for a safe FI tune...
What sux even more is that LTRIMS histogram shows them to be in the 15-20 area around idle and cruise.
There's also 1-2 degrees of KR at WOT around 4k RPM that I will have to sort out eventually...
Gaaah. I guess I will start over where I left off with VE tomorrow... No real changes in the weather to blame...
Thanks,
Rob (Bad30th)
I put the new RAF, VE, OLFA, PE and MAF tables into my original tune yesterday, with MAF and fuel trimming (basically everything) back on. Drove today to work and back logging.
The AFR is about a point leaner than commanded at WOT (which I guess I can adjust PE more rich, but is it OK to tell it whatever it takes to achieve the desired AFR on the wideband ?). I'm commanding 11.2 and it's in the mid 12's which is too lean for a safe FI tune...
What sux even more is that LTRIMS histogram shows them to be in the 15-20 area around idle and cruise.
There's also 1-2 degrees of KR at WOT around 4k RPM that I will have to sort out eventually...
Gaaah. I guess I will start over where I left off with VE tomorrow... No real changes in the weather to blame...
Thanks,
Rob (Bad30th)
12-21-2005, 07:17 AM
#2
TECH Fanatic
Join Date: Aug 2005
Location: Sunny London, UK
Posts: 1,690
Likes: 0
Received 0 Likes
on
0 Posts
With forced induction you are better off without the maf as it will run out of range at atmospheric. Its only designed for NA unless you get one that reads over a wider airflow range.
Most serious FI engines run in speed density mode.
Most serious FI engines run in speed density mode.
12-21-2005, 08:21 AM
#3
Originally Posted by ringram
With forced induction you are better off without the maf as it will run out of range at atmospheric. Its only designed for NA unless you get one that reads over a wider airflow range.
Most serious FI engines run in speed density mode.
Most serious FI engines run in speed density mode.
12-21-2005, 08:36 AM
#4
your both right lol...ringram your correct in that your probably better off without maf & using a 2 or 3 bar setup from hpt or efilive, guitsboy you are also right in that in the past fi cars have run maf just fine. The problem bad 30th is running into is that hes trying to get his commanded to match his actual which will be very difficult to do without a 2 or 3 bar setup.
12-21-2005, 08:37 AM
#5
12 Second Club
Thread Starter
iTrader: (13)
Join Date: Nov 2001
Location: San Diego, CA
Posts: 1,898
Likes: 0
Received 0 Likes
on
0 Posts
I do have the 2-bar MAP HPT enhancement but I still have a 1-bar sensor installed.
Shouldn't I be able to adjust PE to richen up WOT to a safe AFR on the wideband ?
I mean, drivability isn't really a concern over ~4k RPMs, there's basically only WOT AFR to worry about - right ?
I agree that a 2-bar SD setup would be more accurate. Maybe I should get a 2-bar MAP sensor and go for it. Anybody got a part number/price/sponsor ?
Rob (Bad30th)
Shouldn't I be able to adjust PE to richen up WOT to a safe AFR on the wideband ?
I mean, drivability isn't really a concern over ~4k RPMs, there's basically only WOT AFR to worry about - right ?
I agree that a 2-bar SD setup would be more accurate. Maybe I should get a 2-bar MAP sensor and go for it. Anybody got a part number/price/sponsor ?
Rob (Bad30th)