stockish running lean?
#1
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stockish running lean?
Hey huys I have a 00 m6 ss. I only have a p/p tb, k&n fipk2 cutout and a flowmaster weld in at the time. I now have a tsp rumbler catback minus the cutout. My question is, the car put down 338 rwhp and 355 rwtq (std #'s) but I was running really lean. I had a superchips tune and the guy that dynoed the car said I was dangerously lean. Will a tune be worth the money power wise or should I just run a good octane booster or something. I've always dealt with older distributor cars so I'm new to this. I don't want to tune if I'm really no going to get much out of it. Thx in advance!
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The first question always has to be, "Do you trust
the reading". If the guy stuck a probe up one of your
exhaust tips, the first answer is "no".
Now the Superchips tune may lean out the mixture
by intent, and if you were having fuel delivery or
airflow measurement errors you could be put leaner
than intended.
But if it's not pinging and pulling timing, it's probably
not so much a matter of "dangerously lean" as
"dangerously bad at measuring".
If it wasn't screwed into a pre-cat position the data
isn't worth spit.
the reading". If the guy stuck a probe up one of your
exhaust tips, the first answer is "no".
Now the Superchips tune may lean out the mixture
by intent, and if you were having fuel delivery or
airflow measurement errors you could be put leaner
than intended.
But if it's not pinging and pulling timing, it's probably
not so much a matter of "dangerously lean" as
"dangerously bad at measuring".
If it wasn't screwed into a pre-cat position the data
isn't worth spit.
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Hmm you guys have me curious now. My tuner used a tailpipe probe. The first dyno pull was lean at just under 14:1, he richened it and it measured at 12.8:1 but I went from 360+rwhp to 345rwhp (even though I had a pulley the second time, did go to a heavier driveshaft though and it was in summer vs winter) dyno runs were done months apart because the trans grenaded
I have a lc1 sitting in my room, just haven't had time to install it and have a bung welded in
I have a lc1 sitting in my room, just haven't had time to install it and have a bung welded in
#5
a true custom tune is worth it. Remember that a programmer is a pre set tune that is based on a general census of what is needed. a custom tune will look at all that is involved in your specific vehicle. Also much safer with a custom tuner who knows what they are doing vs. just a quick flash from a mail order tuner. What was your a/f readout? how were the curves? (smooth or jagged) you could still have alot of potential in the car.
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Thx guys. Thompson, my lines were smooth. I can't remember what the a/f was tho. I will post up my dyno sheet tho. I don't know too much about dynoes and a/f ratios. All I can remember was that it was 95 degrees in the shop and he didn't even put the fan in front to simulate "driving conditions". Maybe that could affect the a/f as well. I dunno that why I'm asking u fellas haha!
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#11
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I've noticed '00 cars tend to run a little lean. I'd definitely investigate further by installing a WBO2 sensor. They're a good device to have as a safety feature (just like a fuel pressure or oil pressure guage is IMO). It's not the end-all solution for your problems. But, it sure can point you in the right direction when things aren't where they're supposed to be.
If I was a betting man though, I'd say you're really running lean and it's not just a false tailpipe reading.
If I was a betting man though, I'd say you're really running lean and it's not just a false tailpipe reading.
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Quick question. I have a autoscanner that I can plug in. I have a 99. Headers, no cats, no muffler. I really have a problem when its hot outside. I don't have any problems in the morning. When it wants to run like crap and shut off on me in the afternoons, the scanner is saying lean bank 1 and 2. Any suggestions?