My KR dilemma...continued...
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Melting Slicks
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From: Arlington TX
My KR dilemma...continued...
Well I ordered the PACE LS6 descreened MAF and put it on yesterday...I made 6 runs and now I noticed that my LTFT's are way to positive. Before with the GMAFS and Mike's 2001 stock MAF at WOT I was at 0. Now at WOT I am showing +3 to +7 in my LTFT's in B1 and B2. My question is...I know I am supposed to change the MAF tables when switching from my GMAF to the stock one...could this be causing my LFTF's to be running positive instead of 0 or just below? I am still getting the KR with the new MAF but I'm assuming/hoping it is because I need to get everything dialed back in. Another question...why is it that when I put the stock MAF back in my LTFT's didn't change...but when putting in the LS6 MAF...my LTFT's shot up? Any ideas? Thanks.
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Melting Slicks
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From: Arlington TX
Re: My KR dilemma...continued... (los7883)
I was doing some reading and showed that a high or positive LTFT reading suggests the PCM is trying to adjust for a lean condition. Would switching to the larger MAF cause me to now run lean...which would cause the KR? I'm hoping this is it and that all I need to do is adjust my Inj Flow Rate to bring it down?
Melting Slicks
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Re: My KR dilemma...continued... (los7883)
I was doing some reading and showed that a high or positive LTFT reading suggests the PCM is trying to adjust for a lean condition. Would switching to the larger MAF cause me to now run lean...which would cause the KR? I'm hoping this is it and that all I need to do is adjust my Inj Flow Rate to bring it down?
Tech Contributor
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St. Jude Donor '08-'09-'10-'11
Re: My KR dilemma...continued... (Godspeed)
I originally adjusted the MAF table and I was getting 1514 codes all the time. I adjusted the table back to stock and then adjusted with the injector flow rate. All better now.
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Melting Slicks
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From: Arlington TX
Re: My KR dilemma...continued... (SpinMonster)
With the new MAF...could it be that I am running leaner now...which is causing my LTFT's to be high due to the PCM trying to compensate by adding more fuel...also couldn't my new lean condition be causing KR to show up...
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From: My barber didn't know when to quit... Do you?
Re: My KR dilemma...continued... (los7883)
You know what is really funny?
I have an A4 with 3.42s, a SY 3500 as well and a Thunder cam (mine is the 2242/224 on a 114) and I have had pinging issues ever since I got heads and cam done.
My tuner said he installed a few TR cams and they all had pinging at low RPMs like mine does.
I have been adding toloune to each tank of gas which helps the pinging, but does not get rid of it. I have had it tuned several times with a dyno and LS1 Edit and still get the pinging. It may be the cam? :confused:
Probably I am going to try switching cams next year to see if that helps at all. I will be ready for a bigger cam by that time I think. :reddevil
Where in the RPMs does your car ping and how bad is it?
I have an A4 with 3.42s, a SY 3500 as well and a Thunder cam (mine is the 2242/224 on a 114) and I have had pinging issues ever since I got heads and cam done.
My tuner said he installed a few TR cams and they all had pinging at low RPMs like mine does.
I have been adding toloune to each tank of gas which helps the pinging, but does not get rid of it. I have had it tuned several times with a dyno and LS1 Edit and still get the pinging. It may be the cam? :confused:
Probably I am going to try switching cams next year to see if that helps at all. I will be ready for a bigger cam by that time I think. :reddevil
Where in the RPMs does your car ping and how bad is it?
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Melting Slicks
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From: Arlington TX
Re: My KR dilemma...continued... (2000^C5)
It looks like my KR is kicking in from 4300-5600 rpm's...usually don't get any from a roll, but from a stop it kicks in pretty good...so you think it's the TR cam?
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Race Director
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From: My barber didn't know when to quit... Do you?
Re: My KR dilemma...continued... (los7883)
I don't know, it may be, seems like a few people with the Tr cams are having pinging.
Is your pinging loud enough to hear?
Mine is... :cry
Is your pinging loud enough to hear?
Mine is... :cry
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From: Palm City Florida
Re: My KR dilemma...continued... (los7883)
WHat does your IAT table look like?? Did you modify it?
If it's hot by you like it is by me...(95+) then iat temps alone could be causing the pinging...
Use the table to kill some timing above 95 degrees...
Here is what I did...
Starting at 95F (35C) I put these values down each column from 20kpa to 100kpa
35 ->
-1, -2, -3, -4, -5, -5.5, -6, -6.5, -7, -7.5, -8, -8.5
I got this from Robert Judd..
:smash: :smash:
If it's hot by you like it is by me...(95+) then iat temps alone could be causing the pinging...
Use the table to kill some timing above 95 degrees...
Here is what I did...
Starting at 95F (35C) I put these values down each column from 20kpa to 100kpa
35 ->
-1, -2, -3, -4, -5, -5.5, -6, -6.5, -7, -7.5, -8, -8.5
I got this from Robert Judd..
:smash: :smash:
Thread Starter
Melting Slicks
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From: Arlington TX
Re: My KR dilemma...continued... (chuckster)
Before I did the decarb it was loud enogh to hear...afterwards it was gone but was still getting some KR. I didn't pay attention though...my IAT's used to be 120+ but after removing the fog surrounds they stay pretty low when making my runs...today they were kinda of high...all temps were below 98...pretty big change from 120* down to 98*. I don't have LS1 Edit yet...will need to save up for it...but will probably be going to LGM to have everything dialed back in to bring it up back to par. Is there any harm in driving the car if the LTFT's are high right now??? I''m assuming I am running lean right now...will it hurt the engine or will it only affect it at WOT???
Race Director
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From: Palm City Florida
Re: My KR dilemma...continued... (los7883)
One more thing..I have NEVER seen an aftermarket MAF FIX K/R. In fact most of the time they cause it...
I'd go back to the Stock MAF descreened... Check your K/R again..
JMHO.. The MAF is a 20 min swap...
I'd go back to the Stock MAF descreened... Check your K/R again..
JMHO.. The MAF is a 20 min swap...
Le Mans Master
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From: Hot Springs AR
Re: My KR dilemma...continued... (los7883)
Carlos,
Considering that when we put on my stock MAF (with the screen, for everyone else) that the KR basically went away, I think I'd return the LS-6 MAF for a stocker. Then you can tweak the tables as necessary.
As far as damage is concerned, the PCM is able to compensate for the lean values (since you're not getting a code and Check Engine light), and the actual detonation is also being handled, I don't think you're endangering the engine.
Hope this helps, and have a good one,
Mike
Considering that when we put on my stock MAF (with the screen, for everyone else) that the KR basically went away, I think I'd return the LS-6 MAF for a stocker. Then you can tweak the tables as necessary.
As far as damage is concerned, the PCM is able to compensate for the lean values (since you're not getting a code and Check Engine light), and the actual detonation is also being handled, I don't think you're endangering the engine.
Hope this helps, and have a good one,
Mike
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Melting Slicks
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From: Arlington TX
Re: My KR dilemma...continued... (VetteDrmr)
Thanks guys...I am currently selling the Granatelli, contacted PACE to return their LS6 MAF, and am now looking for a used LS1 MAF. There is nothing wrong with the Pace or Granatelli MAF, from what they told me...their MAF's are calibrated for stock to semi-modded corvettes. They said it isn't calibrated for a Vette with the mods I have...to have Granatelli Motorsports recalibrate it would cost $125+...yea whatever...I am now in the market for a stock MAF if anyone has an extra one laying around...or if anyone is looking for a Granatelli or LS6 MAF... :cheers:
Matt...still haven't ran race gas through...when we put the stock MAF (Mike's MAF) back on the KR went away...I'll post a table of my run with the stock one back on. Give me a second.
[Modified by los7883, 11:32 PM 7/1/2003]
Matt...still haven't ran race gas through...when we put the stock MAF (Mike's MAF) back on the KR went away...I'll post a table of my run with the stock one back on. Give me a second.
[Modified by los7883, 11:32 PM 7/1/2003]
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From: Palm City Florida
Re: My KR dilemma...continued... (los7883)
Something is really wrong..I know different years vary..But the most timing I saw you get without K/R is 19 degrees???
I have a 2000 and get clean 29 degree WOT...
Even with the Thunder Cam you should be able to get better than that. C5noir got 30 degree WOT with the 224/224 TR cam..
Who is flashing your PCM again? See if you can get a copy of the flash and post it..
Put the stock MAF on.
Fill her up with Racing Gas...
I swear you are running in the low octane table...
Also one more important thing...Show us your O2's during all that k/R... If you are running really lean you will knock yourself to hell...
[Modified by chuckster, 10:48 PM 7/1/2003]
I have a 2000 and get clean 29 degree WOT...
Even with the Thunder Cam you should be able to get better than that. C5noir got 30 degree WOT with the 224/224 TR cam..
Who is flashing your PCM again? See if you can get a copy of the flash and post it..
Put the stock MAF on.
Fill her up with Racing Gas...
I swear you are running in the low octane table...
Also one more important thing...Show us your O2's during all that k/R... If you are running really lean you will knock yourself to hell...
[Modified by chuckster, 10:48 PM 7/1/2003]
Thread Starter
Melting Slicks
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From: Arlington TX
Re: My KR dilemma...continued... (chuckster)
Something is really wrong..I know different years vary..But the most timing I saw you get without K/R is 19 degrees???
I have a 2000 and get clean 29 degree WOT...
Even with the Thunder Cam you should be able to get better than that. C5noir got 30 degree WOT with the 224/224 TR cam..
Who is flashing your PCM again? See if you can get a copy of the flash and post it..
Put the stock MAF on.
Fill her up with Racing Gas...
I swear you are running in the low octane table...
Also one more important thing...Show us your O2's during all that k/R... If you are running really lean you will knock yourself to hell...
I have a 2000 and get clean 29 degree WOT...
Even with the Thunder Cam you should be able to get better than that. C5noir got 30 degree WOT with the 224/224 TR cam..
Who is flashing your PCM again? See if you can get a copy of the flash and post it..
Put the stock MAF on.
Fill her up with Racing Gas...
I swear you are running in the low octane table...
Also one more important thing...Show us your O2's during all that k/R... If you are running really lean you will knock yourself to hell...
With the stock MAF on we were running right at 0 for my LTFT's in B1 and B2. After I installed the PACE MAF my LTFT's went way too high +9. So yea...now I'm running real lean...So I'm selling my Granatelli...sending my PACE MAF back, and looking for a stock MAF...once I get a stock one...and the KR has gone down to <1* at WOT...I will put the race gas in to see if this fixes it for sure...if it does...then I will take it back to have the timing increased and the A/F tuned back in...by O2's are you talking about the voltages? What should I be looking for there?
Le Mans Master
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Re: My KR dilemma...continued... (chuckster)
I have to agree with chuckster. Something is up if you are on the verge of KR with 19 degrees of timing, which is probably in the low octane table.
Going to the stock MAF is a good next step.. Then you should be able to start adding more timing and see if the KR comes back, but you would need LS1edit to do so.
[Modified by MattG, 11:04 PM 7/1/2003]
Going to the stock MAF is a good next step.. Then you should be able to start adding more timing and see if the KR comes back, but you would need LS1edit to do so.
[Modified by MattG, 11:04 PM 7/1/2003]
Thread Starter
Melting Slicks
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From: Arlington TX
Re: My KR dilemma...continued... (MattG)
If I am running super-lean right now won't this kick me into my lower octane table? I'm hoping this is the case...but I won't know for sure until I find a stock MAF...
[b]DOESN'T ANYBODY HAVE AN EXTRA ONE LAYING AROUND???[b]
:lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol:
[b]DOESN'T ANYBODY HAVE AN EXTRA ONE LAYING AROUND???[b]
:lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol: