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different IFRs for greentop 42#'s ?

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Old Jun 21, 2006 | 12:41 PM
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Default different IFRs for greentop 42#'s ?

I've been looking at some of the uploaded tunes on Horists' respository for cars with 42# greentop injectors.

They have varying IFR table values even though they all have the same injectors :

149338874.zip

43.65182 43.65182 43.65182 43.65182 43.65182 43.65182 43.65182 43.65182 43.65182 43.65182 43.65182 43.65182 43.65182 43.65182 43.65182 43.65182 43.65182




21553618252.zip

38.44336 38.62938 38.93941 39.06342 39.31144 39.68347 39.86949 40.17952 40.24152 40.55155 40.79957 40.92358 41.17160 41.41962 41.66765 41.85366 42.03968




19595224909.zip

38.44336 38.62938 38.93941 39.06342 39.31144 39.68347 39.86949 40.17952 40.24152 40.55155 40.79957 40.92358 41.17160 41.41962 41.66765 41.85366 42.03968



216197490.zip

45.13995 45.57399 45.94602 46.00803 46.38006 46.75209 46.81410 47.24814 47.37215 47.80618 47.93019 48.24022 48.48824 48.73627 49.04629 49.29431 49.54234

Why is this ?

What are the IFR values for 42# greentops supposed to be on an otherwise stock tune ? (Tried search, found nothing).

I'm trying to figure out why my fueling is still all jacked up now that I've switched to a new bottom and and an LS6 cam.

Thanks,
Rob (Bad30th)

Last edited by Bad30th; Jun 21, 2006 at 12:47 PM.
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Old Jun 21, 2006 | 01:15 PM
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Originally Posted by Bad30th
216197490.zip

45.13995 45.57399 45.94602 46.00803 46.38006 46.75209 46.81410 47.24814 47.37215 47.80618 47.93019 48.24022 48.48824 48.73627 49.04629 49.29431 49.54234

Why is this ?

What are the IFR values for 42# greentops supposed to be on an otherwise stock tune ? (Tried search, found nothing).
Those should be pretty close. Common sense tells you an injector rated at 42lb/hr on 43.5psi would flow more than that at 58psi. Why not just use the injector spreadsheet, it makes things much more simple?

Oh yeah, and your fueling is all jacked up because the flow characteristics are different. Different cam, probably a different quench, different pistons, etc.
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Old Jun 21, 2006 | 02:03 PM
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Thanks for the reply.

After reading more it appears some people also alter this table to correct for tuning A/F. Ewwww.

I never understood what values to plug into the spreadsheet, can someone pls explain ? I know fuel pressure = 58psi, but what do I put in for rated flow pressure and flow rate ?

Today I'm going to attempt to start from scratch from my stock tune, adding known good values to try to straighten things out.

Rob (Bad30th)
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Old Jun 21, 2006 | 02:07 PM
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I would not use any of those tables, I'd use the spreadsheet.

Values:
Injector rated fuel pressure: the manufacture post the exact pressure the injector was tested at. yours are probably 43.5

Your rail fuel pressure: Stock is normally 58psi, If you have a boost pump or aftermarket hi flow pump i've seen pressure hover around 60 to 62psi.

Injector rated flow rate: basically what it states. 42lbs in your case


For example, i did this for 42lbs injectors rated at 43.5psi, 58lbs rail pressure

48.49827788 48.80053386 49.10092925 49.39949798 49.69627298 49.9912862 50.28456864 50.57615042 50.86606077 51.15432813 51.4409801 51.72604355 52.00954459 52.29150865 52.57196044 52.85092404 53.12842289


As you can see, no where near what some of the others were set at, as they were wrong, since they were compensating for not properly calibrating the maf, ve, pe table ect.

Last edited by SmokingWS6; Jun 21, 2006 at 02:13 PM.
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Old Jun 21, 2006 | 02:09 PM
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Originally Posted by SMOKINV8
42lb/hr on 43.5psi
Are these the numbers I need to plug into the injector spreadsheet ?

Sorry for being a noob, trying to learn...

plugging in those values give me :

48.4983
48.8005
49.1009
49.3995
49.6963
49.9913
50.2846
50.5762
50.8661
51.1543
51.4410
51.7260
52.0095
52.2915
52.5720
52.8509
53.1284

Is that correct ?

Rob (Bad30th)
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Old Jun 21, 2006 | 02:14 PM
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Originally Posted by Bad30th
Are these the numbers I need to plug into the injector spreadsheet ?

Sorry for being a noob, trying to learn...

Rob (Bad30th)

scroll up two post. i edited my post
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Old Jun 21, 2006 | 02:19 PM
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Yippee, OK, I got the same numbers.

I will give those a try, mine are WAY different in my current tune, 42.22570 to 45.449. Maybe that's why it's trimming in so much fuel.

Thanks for the explanation.

Rob (Bad30th)
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Old Jun 21, 2006 | 04:01 PM
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Originally Posted by SmokingWS6
I would not use any of those tables, I'd use the spreadsheet.

Values:
Injector rated fuel pressure: the manufacture post the exact pressure the injector was tested at. yours are probably 43.5

Your rail fuel pressure: Stock is normally 58psi, If you have a boost pump or aftermarket hi flow pump i've seen pressure hover around 60 to 62psi.

Injector rated flow rate: basically what it states. 42lbs in your case


For example, i did this for 42lbs injectors rated at 43.5psi, 58lbs rail pressure

48.49827788 48.80053386 49.10092925 49.39949798 49.69627298 49.9912862 50.28456864 50.57615042 50.86606077 51.15432813 51.4409801 51.72604355 52.00954459 52.29150865 52.57196044 52.85092404 53.12842289


As you can see, no where near what some of the others were set at, as they were wrong, since they were compensating for not properly calibrating the maf, ve, pe table ect.
AMEN
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Old Jun 21, 2006 | 04:50 PM
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Glad to see you're willing to re-do some stuff to get it right, you'll be thanking yourself later.
Originally Posted by Bad30th
Maybe that's why it's trimming in so much fuel.
That should also help alleviate some of the fueling fluctuation you've been seeing on a day to day basis.
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Old Jun 21, 2006 | 10:53 PM
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Why arent they all the same if all injectors have the same fuel preasure,
ive looked at different files and some have it same across and some is like this

For example, i did this for 42lbs injectors rated at 43.5psi, 58lbs rail pressure

48.49827788 48.80053386 49.10092925 49.39949798 49.69627298 49.9912862 50.28456864 50.57615042 50.86606077 51.15432813 51.4409801 51.72604355 52.00954459 52.29150865 52.57196044 52.85092404 53.12842289
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Old Jun 22, 2006 | 10:43 AM
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Two answers to this......1 someone was running different fuel pressures which changes the IFR factor.......2 someone did not know what they were doing. The numbers stated below look about right for 58# of fuel pressure.

Originally Posted by dc96819
Why arent they all the same if all injectors have the same fuel preasure,
ive looked at different files and some have it same across and some is like this

For example, i did this for 42lbs injectors rated at 43.5psi, 58lbs rail pressure

48.49827788 48.80053386 49.10092925 49.39949798 49.69627298 49.9912862 50.28456864 50.57615042 50.86606077 51.15432813 51.4409801 51.72604355 52.00954459 52.29150865 52.57196044 52.85092404 53.12842289
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Old Jun 22, 2006 | 11:22 AM
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Didnt I give you the values a while back Rob? What, you dont trust me? I was thinking of reflashing mine and starting from scratch too. Good luck getting things inline.
Nino
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Old Jun 22, 2006 | 11:29 AM
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Originally Posted by ninobrn99
Didnt I give you the values a while back Rob? What, you dont trust me? I was thinking of reflashing mine and starting from scratch too. Good luck getting things inline.
Nino
Just trying to start fresh and make 100% sure of all changes from stock, and it appears that I did have the wrong values in there. I still have the crazy fuel trimming +25% LTRIMS almost across the board, starts to drop to the high teens after warmed up, but sometimes the STRIMS go high too. Crazy.

After thinking this over, I'm unsure how changing the values in the IFR table to the (correct) higher value than I had will help my lean fueling/excessive trimming.

If we're telling the PCM that the injectors flow more in a given state it seems like it will lean me out even more ?

At least the wideband agrees that it's lean and the trimming is keeping it at stoich.

I will know more this afternoon when I try flashing the car with my new-from-stock tune.

Rob (Bad30th)
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Old Jun 22, 2006 | 11:44 AM
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If you input the correct IFRs and the values were higher than they are now, I would think you would get a bit richer. I might be looking at it wrong though. You sure you dont have any leaks? Its the same on both banks right? If it doesnt change after adjusting your VE, then its something mechanical.
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Old Jun 22, 2006 | 02:48 PM
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Update : good news and bad news. With the new tune and calculated IFR table the car fired right up and idled - I was excited until I backed it out of the driveway and discovered I couldn't get it over 2k RPM without it bogging/surging and being generally very unhappy. Tonight I will try the new stock tune but with the old IFR table to see how that works.

Any ideas why the calculated IFR table wouldn't work on an otherwise stock tune ? (raised idle, lowered fan settings, used my old spark table, old RAF table, that's about it except for transmission settings). I put my old tune back in and it fired right up and scoots down the road - but with 25% LTRIMS and STRIMs that are positive ranging from 5-20 ! That's adding like 30-45% more fuel ! ...and the wideband agrees that the net result is stoich, ~14.7:1

I'm confident it's not anything mechanical, I have a brand new forged bottom end and new LS6 cam/lifters - and the swap didn't cure the fueling problem. Blower bypass is vented to atmosphere.

Rob (Bad30th)
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Old Jun 22, 2006 | 02:51 PM
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well of course! if you had everything balanced (improperly balanced, but balanced nonetheless) then if you take ONE thing out of balance, the rest is gonna crap out on you. now it's time to start bringing everything else back into balance, so start doing VE. didn't Nino show you all this stuff already?
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Old Jun 22, 2006 | 02:54 PM
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I didnt show him, but I did help with his raf You're going to want to get the raf on point again, once thats done, move to ve. Do a few passes, add some more timing, do a few more passes of the ve, add a bit more timing, touch the ve again, then go for the maf and PE. Wish I was around to help Wanna wait till August?
Good luck Rob!
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Old Jun 22, 2006 | 02:56 PM
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Originally Posted by RedHardSupra
well of course! if you had everything balanced (improperly balanced, but balanced nonetheless) then if you take ONE thing out of balance, the rest is gonna crap out on you. now it's time to start bringing everything else back into balance, so start doing VE. didn't Nino show you all this stuff already?
Yes, I know how to step through SD and MAF tuning, but I guess I'm just surprised that the stock tune won't run better in my setup with just scaling the injectors since it's basically stock (LS6 cam) with some slightly larger combustion chambers in the heads. Keeping out of boost it should run like a stock LS6, right ?

Thanks for the ideas guys. I guess I will try to start from the top with the new IFR table and do RAF, VE and MAF and see what happens ?

Rob (Bad30th)
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Old Jun 22, 2006 | 02:59 PM
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Originally Posted by ninobrn99
I didnt show him, but I did help with his raf You're going to want to get the raf on point again, once thats done, move to ve. Do a few passes, add some more timing, do a few more passes of the ve, add a bit more timing, touch the ve again, then go for the maf and PE. Wish I was around to help Wanna wait till August?
Good luck Rob!
LOL, give me SOME credit guys. I know enough to be dangerous.

idle speed, idle timing, RAF in gear and park, SD mode with my wideband to set VE by AFR error %, turn MAF back on and use AFR error % to adjust MAF table, measure actual vs. desired airflow to ensure they're close, set PE fueling and watch for knock, lather, rinse repeat...

Edit : Ah, I just had a light bulb moment. The RAF that I plugged in is from my old 222/224:114 cam. I now have an LS6 cam, and -4cc valve reliefs on the new pistons. I will redo the RAF table and see what that does for me. Thanks for bearing with me guys, learning hurts sometimes, LOL.

Rob (Bad30th)

Last edited by Bad30th; Jun 22, 2006 at 03:09 PM.
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Old Jun 22, 2006 | 03:21 PM
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if you're still having problems send me your bin, i'll take a look.
and yes, raf from a much bigger cam is gonna be very, very different
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