try again
Thread Starter
Teching In
Joined: Apr 2002
Posts: 20
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try again I tried posting about this issue in the racing section but I'll try here, hope you guys don't mind. 2001 SS, 6M, 15k miles. MODS:
TBB, !AGR, !CAGS, direct flow lid, K&N filter, SLP MAF, SLP tuned lengths, MAFT, Random tech cats, Corsa catback, fan switch, 160 t-stat, BMR SFCs&LCAs, Bosch Plat 4+.
Stock run:13.255@107.16(2.217 60')
moded run:13.11@111.27(2.262 60')
Autotapped and adjusted, LTtrim slightly + but close to 0, WOT, .90x avg, no knock retard, timing all over the place but usually around 18-22. WTF, quite a bit of modding for such a short gain? Granted my 60's suk but come on? I am switching the plugs to AC delcos 2-morrow, car seems a bit rough. Not to many misfires when autotapped and all at idle. Could the plugs be screwing it up that much and why?
Thanks all.
TBB, !AGR, !CAGS, direct flow lid, K&N filter, SLP MAF, SLP tuned lengths, MAFT, Random tech cats, Corsa catback, fan switch, 160 t-stat, BMR SFCs&LCAs, Bosch Plat 4+.
Stock run:13.255@107.16(2.217 60')
moded run:13.11@111.27(2.262 60')
Autotapped and adjusted, LTtrim slightly + but close to 0, WOT, .90x avg, no knock retard, timing all over the place but usually around 18-22. WTF, quite a bit of modding for such a short gain? Granted my 60's suk but come on? I am switching the plugs to AC delcos 2-morrow, car seems a bit rough. Not to many misfires when autotapped and all at idle. Could the plugs be screwing it up that much and why?
Thanks all.
Re: try again It looks like your PCM is in "low octane" mode. Next time you fill up, make sure you go to Chevron or one of the bigger names for gas. Then right after your fill up got for some auto tap logs. And see what the timing does.
You may be getting some KR and that sets the PCM into the low octane tables.
Just a thought.
Ryan K. <img border="0" title="" alt="[Cool]" src="gr_images/icons/cool.gif" />
You may be getting some KR and that sets the PCM into the low octane tables.
Just a thought.
Ryan K. <img border="0" title="" alt="[Cool]" src="gr_images/icons/cool.gif" />
Thread Starter
Teching In
Joined: Apr 2002
Posts: 20
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Re: try again Thanks for the reply Ryan. KR is 0 most of the time, when it shows up it is really small, maybe 1-2. I think my problem is much bigger though, car has been eating gas. Kind of confusing if O2 sensors indicate ok, I had to adjust WOT real lean, I think I ended at like %10-%12. Even with that, the car still sucks gas? <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" />
Re: try again I think that with your MAFT, you want to get the Ltrims to be slightly negative, between 0% and -5%. what base setting you you on??? If you are at 0% base, go to the 5% rich base setting and set the WOT switch back to no change.
Drive the car around and let the PCM re-learn. You should notice that the Ltrims are going down, even past 0% to a negative number, thats what you want. once you have negative Ltrims, them do some WOT runs and see where your O2 sensor output is. Adjust the WOT setting on the MAFT to achieve about 880mV to 890mV on the O2s.
If your engine is still "eating gas", then check out possible reasons.
The comment about the "low octane timing table" could be why you have low timing. I think at WOT, you should get about 27* to 28* timing. Be sure to put in good gas. I run only 93 octane in my car.
Drive the car around and let the PCM re-learn. You should notice that the Ltrims are going down, even past 0% to a negative number, thats what you want. once you have negative Ltrims, them do some WOT runs and see where your O2 sensor output is. Adjust the WOT setting on the MAFT to achieve about 880mV to 890mV on the O2s.
If your engine is still "eating gas", then check out possible reasons.
The comment about the "low octane timing table" could be why you have low timing. I think at WOT, you should get about 27* to 28* timing. Be sure to put in good gas. I run only 93 octane in my car.
Thread Starter
Teching In
Joined: Apr 2002
Posts: 20
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Re: try again I ran at the track .89 and .91 on the 02's(adjusting my WOT). Picked up some trap speed when I was richer. I thought .88 is pretty lean, no? I just got her back after new plugs so I am tuning tonight. I will adjust my base to get slightly -LT. Right now my base is +10. 27* and 28* seem like high goals for a 2001, I have heard of much less. Always put 93 in, even though it is $1.70's around here. Damn gas costs more than the car itself?!? Thanks for the reply.
Thread Starter
Teching In
Joined: Apr 2002
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Re: try again New plugs in, first ATAP run, amazed with results:
LT=+1.131
O2=.907
KR=0
TA=24*@3300rpms
=27*@5500rmps
TA increasing pretty damn linearly, what do you think guys? I think she is fixed and ready for the track. I just got into ATAP but this seems near perfect, no?? Anyway, unless anyone has any suggestions on adjustments, I'm leaving it be.
BASE=+10%
WOT=-10%(pretty low, but that's what it took)
Let me know what ya'll think, thanks again for all of the help!
LT=+1.131
O2=.907
KR=0
TA=24*@3300rpms
=27*@5500rmps
TA increasing pretty damn linearly, what do you think guys? I think she is fixed and ready for the track. I just got into ATAP but this seems near perfect, no?? Anyway, unless anyone has any suggestions on adjustments, I'm leaving it be.
BASE=+10%
WOT=-10%(pretty low, but that's what it took)
Let me know what ya'll think, thanks again for all of the help!
