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Predator confusion

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Old Dec 3, 2003 | 09:18 PM
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Question Predator confusion

I just installed a Predator programmer on my Z. At first with the stock tune I was getting huge knock. I did not bother to do the live scan because it sounded like a marble in a tin can. I then started to play with the spark and fuel. I reduced the spark by 2.5%(no change), then 5%(still too much detonation), then 7.5% (still audible detonation), then I tried the max 10%( least detonation). I also increased fuel to +3%. The 02 readings stay around 780 to 880 and I still get 2-3deg of spark retard under 2000 rpm. I have had a low rpm ping for a bit now, before the Predator. The spark retard reduces to 1% under full throttle. The timing under light throttle hits 37deg and reduces to around 25deg under full throttle. Is all this normal? Should I add more fuel? Is it common to need to reduce the max timing or add so much fuel? I have nothing to go by. Some examples would be helpful.
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Old Dec 3, 2003 | 09:37 PM
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Originally Posted by ZtwentyATE
I just installed a Predator programmer on my Z. At first with the stock tune I was getting huge knock. I did not bother to do the live scan because it sounded like a marble in a tin can. I then started to play with the spark and fuel. I reduced the spark by 2.5%(no change), then 5%(still too much detonation), then 7.5% (still audible detonation), then I tried the max 10%( least detonation). I also increased fuel to +3%. The 02 readings stay around 780 to 880 and I still get 2-3deg of spark retard under 2000 rpm. I have had a low rpm ping for a bit now, before the Predator. The spark retard reduces to 1% under full throttle. The timing under light throttle hits 37deg and reduces to around 25deg under full throttle. Is all this normal? Should I add more fuel? Is it common to need to reduce the max timing or add so much fuel? I have nothing to go by. Some examples would be helpful.

detonating at low rpm? how can u tell this im curious? does it just show up in knock?

o u want those o2s to stay about 890-920. WOT spark should be at about 30* and u shouldnt get any knock, what are all your mods?
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Old Dec 3, 2003 | 09:40 PM
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for now i would put the fuel all the way up and put the timing down and try and get a custom tune for that joker. 780-880 is too big of a range for the o2s like i said they should be really close, mine go from about 895-905 just let me knwo your mods and what it was doing before u messed with the timing and PE
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Old Dec 3, 2003 | 10:40 PM
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My mods are in the sig. Intake, exhaust, and the Predator is it. No cams or heads or even headers. I should not need a custom tune.....right? The predator shows me the KR as I putter around town. Under 2000 rpms and no acceleration I get no KR. Jab the throttle a little bit and viola, knock retart tu the tune of 2-3 degrees (audible too). Floor it and it almost goes away. I am thinking of increasing the fuel to 4%. Any help is greatly welcome.
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Old Dec 4, 2003 | 12:07 AM
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UPDATE: I just took my car for some high speed runs and the O2 readings are right at 920-940 with 0 KR at WOT. I still get up to 6 deg. KR at 13-1800 rpm under light throttle only. ( I think the Predator only messes with WOT timing) Light throttle over 1800 and nothing. Wierdest ****. I think I need to replace the plugs and they may do the trick. I dunno.....
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Old Dec 4, 2003 | 01:33 AM
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You would be correct in assuming predator only affects WOT A/F. I would write a program with the predator set (0) timing and add 5% fuel. Sounds like youre running lean
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Old Dec 4, 2003 | 01:35 AM
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Dude if your still running the stock plugs go outside and beat yourself a little will ya!

Ok, now then. The predator baseline will rasie WOT spark to about 33*. Thats 4*more than stock. You can add or remove 2* from the predator, not 1, but 2*.

The O2 are not good unless your at WOT, so dont even worry about them unless. Same as the timing, you can get 40*on a decel no load etc... but whats it matter. YOu want to look at timing during WOT, KR, and O2. If you had a logger it would be way better. I have used the Predator for a few months now, and tuned my old TR224 cam very well with it, it is a good tool. BUT you have to work with your vendor and give them the data critical to get a good tune. Communication is the key.

Good-luck,
lemme know if you need more help.

Charlie.
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Old Dec 4, 2003 | 08:09 AM
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get your part throttle LTFT numbers i bet they are gonna be lean as hell. all i had was intake stuff done and it threw my tune WAY off
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Old Dec 4, 2003 | 09:28 AM
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Do you have a GMAF on it? There should be no reason for spark knock if you've not made changes to affect it. You may want to download it back to stock and take it to a dealer and have them look at it. My friend in FL had the same problem. Don't try to do it with a predator, that shouldn't be the fix.

There is a known spark knock issue with 01-02's that they have a "fix" for.

Last edited by Redlinez; Dec 4, 2003 at 10:43 AM.
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Old Dec 4, 2003 | 10:32 PM
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Are you using 91 or mabe 93 octane like it says to? Diablo told me they raise the timing more than stock from 2000rpm to red line in the Pred tune. I added more and still get no knock. Runs great.
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Old Dec 5, 2003 | 06:13 PM
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My max timing is only hitting 27* under wot. I am using 91 octane. I was unaware of a spark problem with 01-02 camaros. I plan to return my car to stock and take it in to the dealer. It appears to be a problem with the O2 sensor getting water in it. It is bulliten # 02-06-04-023A. The car feels a whole lot faster with the settings I have. There is some pinging, but not much, 1-2*.
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Old Dec 5, 2003 | 06:18 PM
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I wouldnt be comfy with pinging, even it was only 2*. Still 2* too much, and BTW the predator is not the most accurate data retreival system out there. Trust me, I have been logging with other software, and they show a slight bit of KR when the Predator shows ZERO. Not cool. 27* is less than stock, with the base Predator you should be around 33*. Stock 29*.
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