How does the IFR table affect the PE table?
Thread Starter
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From: Waterloo, Ontario
How does the IFR table affect the PE table? Hey guys a quick question if I scaled my IFR table 105%(to make my 30's runn smaller)how would that change affect my PE table? Which way would I scale it? For example car is set up right now with the IFR at 105% over stock-and PE has been set to 12.9 on the dyno. Now I want to change the IFR from 105 to 107-what change would be required in the pe table to maintain that 12.9AFR at wot?
Why is your IFR table only scaled 105% for 30#'ers? There are several threads here that show the correct IFR table for the SVO's. You need to only adjust the IFR table once and then change the VE table to compensate for the correct fueling. You don't want to adjust the IFR table for fueling as it is a set table.
your comparing apples and banannas in this thread.
You need the IFR table to be as close as possible, so you know the fueling.
You want the PE table to be what you want the commanded air fuel to be.
It would only be a poorly educated guess for the answer to your question.
Ryan
You need the IFR table to be as close as possible, so you know the fueling.
You want the PE table to be what you want the commanded air fuel to be.
It would only be a poorly educated guess for the answer to your question.
Ryan
Thread Starter
8 Second Club
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From: Waterloo, Ontario
Basically I followed this method from Horist:
Basically the formula people seem to use is your new injector flow rate @ 3 bar / old injectors @ 3 bar
so depends on what kinda car you have and the year...
I'm not sure if the GM Injector ratings are 3 bar or 4 bar...
98, 01, and 02 F-Bodies were 28lb/hr
99 and 00 were 26 lb/hr
I'm not sure if GM did anything diff w/vettes
When I was scaling mine I took
42lb @ 3 bar, and then 26lb @ 3bar (00) and and came up w/a factor of 1.62
I tried it also assuming 26lb/hr was already 4 bar, and came w/a scalar of 19x% which caused the car to run like poop.. way too lean
the 1.62 * 100 = 162% scalar worked much better for me..
So I'd just do 30/old injectors as a starting point
so either 30/26 = 1.15 = 115%
or 30/28 = 1.07 = 107%
Use this as a starting point, then get your LTRIMS back down to 0
__________________
Mike Horist
00 WS6 (TA) | 04 WS6 (GTP Comp G)
Mike \\#at&\\ horist \\&dot$\\com
I checked my average and it was -7 at first so that's whay i just scaled them 105. Remember this is a Z06 and they are super sensitive to changes in airflow after 02. The car is set up I just threw to error codes 171 and 175, rich codes for bank 1 and 2. So I just need to lean it up a bit more but I'm wondering how will afffect the pe table.
Basically the formula people seem to use is your new injector flow rate @ 3 bar / old injectors @ 3 bar
so depends on what kinda car you have and the year...
I'm not sure if the GM Injector ratings are 3 bar or 4 bar...
98, 01, and 02 F-Bodies were 28lb/hr
99 and 00 were 26 lb/hr
I'm not sure if GM did anything diff w/vettes
When I was scaling mine I took
42lb @ 3 bar, and then 26lb @ 3bar (00) and and came up w/a factor of 1.62
I tried it also assuming 26lb/hr was already 4 bar, and came w/a scalar of 19x% which caused the car to run like poop.. way too lean
the 1.62 * 100 = 162% scalar worked much better for me..
So I'd just do 30/old injectors as a starting point
so either 30/26 = 1.15 = 115%
or 30/28 = 1.07 = 107%
Use this as a starting point, then get your LTRIMS back down to 0
__________________
Mike Horist
00 WS6 (TA) | 04 WS6 (GTP Comp G)
Mike \\#at&\\ horist \\&dot$\\com
I checked my average and it was -7 at first so that's whay i just scaled them 105. Remember this is a Z06 and they are super sensitive to changes in airflow after 02. The car is set up I just threw to error codes 171 and 175, rich codes for bank 1 and 2. So I just need to lean it up a bit more but I'm wondering how will afffect the pe table.
Here is a thread that might be helpful.
https://ls1tech.com/forums/pcm-diagnostics-tuning/344371-what-s-good-pe-scale-factor-10-5-afr.html
https://ls1tech.com/forums/pcm-diagnostics-tuning/344371-what-s-good-pe-scale-factor-10-5-afr.html
TECH Resident
Joined: Aug 2004
Posts: 875
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From: Portland Oregon
There is a sticky at the top of the fueling page that will lead you thru the calculation for new injectors. Somewhere there is a spreadsheet that will make the calculation for you to check your numbers. The SVO 30's are rated at 40 psi, C5 is 58 psi. Use the calculation, don't forget the square root in the formula. I don't know why but it works. I just made the same change on a LS1 car and the new injector rate for 30lb SVO was 138%. With a ZO6 you have 28lb injectors to start so your number will be less.
Then I scaled the PE to 93%. It's good starting point, I'm still fine tuning. Good luck.
Then I scaled the PE to 93%. It's good starting point, I'm still fine tuning. Good luck.
