LT1-LT4 Modifications 1993-97 Gen II Small Block V8

Running really rich.

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Old Jun 5, 2006 | 12:20 PM
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Default Running really rich.

Well, I got on the dyno this past weekend. Some details about my car...it's a 96 camaro Z28 with full exhaust(TPIS mid-lengths and a flowmaster catback), ported heads which flow in the mid 270s, and a cam which is the TPIS ZZ409. And I had the computer tuned by Madwolf(mail order tune), but I think he messed up a little bit on the tune. And you'll see that when you look at the dyno graph.

Anyways, it cut out really bad up top when it was getting really fat/rich. Do you guy think that it cutout because it was running so rich? Maybe the spark arced? The opti only has 50K on it, and the car runs just run at idle and everywhere else in the RPM but up top, and I just replaced the coil with a MSD coil about 50 miles ago. The spark plugs where replaced last June when I put heads on the car was well. And the wires all appear to be in good shape. I couldn't find anything wrong with the wires.

Anyways, here are the pictures of the dyno.




I emailed Ion to see if he could help me out and retune my car, so it isn't running so rich. Because running 10:1 is pretty bad. I'm hoping that the car is just getting too much fuel, but any other ideas would be great.

I know the car has a ton more power left in it, because a buddy of mine with almost the same setup put down 370rwhp the very same day.

Thanks.
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Old Jun 5, 2006 | 12:32 PM
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what injectors and fuel pressure are you running?
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Old Jun 5, 2006 | 12:39 PM
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Stock injectors and fuel pressure regulator.
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Old Jun 5, 2006 | 02:50 PM
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lean it out to 12.5-12.7 and you should get 350 easy
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Old Jun 5, 2006 | 02:56 PM
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Also may want to run a datalogger to see what your o2's are reading. Rule out any mechanicle issue before the tune.
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Old Jun 5, 2006 | 02:58 PM
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Originally Posted by Honda Hunter
Also may want to run a datalogger to see what your o2's are reading. Rule out any mechanicle issue before the tune.
i agree, its pretty hard to belive that a well known tuner could get it that far off. unless he was giving the wrong information.
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Old Jun 5, 2006 | 03:04 PM
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I learned the hard way. Most mailorder tunes will be just about there and should only need some minor tweeking after it's dynoed. Something that far off for some reason makes me think false lean.
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Old Jun 5, 2006 | 05:53 PM
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Originally Posted by Honda Hunter
I learned the hard way. Most mailorder tunes will be just about there and should only need some minor tweeking after it's dynoed. Something that far off for some reason makes me think false lean.
You learned the hard way? Also what do you mean by a false lean?

What is the normal limit on stock injectors? I thought about upgrading to a 30lb set when I get the computer retuned.
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Old Jun 5, 2006 | 06:01 PM
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I learned the hard way meaning I went balistic because I felt my mail order tune was garbage but in the end I found out it was my motor that was trash. False lean meaning you may have a header leak making the o2 sensors believe youre running lean. Could also be a bad o2. Data logger would tell you because it would show the o2 being stuck or reading funny. I dont know the stock limit of the injectors but look at the duty cycle to see if youre in the clear or not. I believe youre not suppose to be above 85%-90%. That will tell you if you should get bigger injectors. !paragraphs
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