Engine Detonation???
02-08-2002, 05:53 PM
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Engine Detonation??? Last month I had my t/a on the dyno for the first time. As the RPM hit around 5000 to 5500 the engine would "detonate" and lose HP. The guy who performed the dyno said that LS1s are sometimes known to do this on the dynometer and that it may not even do it on the street in daily driving.
The problem!... is that it is still detonating, even during daily street use. I have ruled out the bad gas theory. What else could it be?
If anyone has had any experience with this sort of thing, I could really use the advice. Since no codes are being tripped, my next step is to change the plugs and wires, unless informed otherwise. <img src="images/icons/confused.gif" border="0">
Thanks!!!
The problem!... is that it is still detonating, even during daily street use. I have ruled out the bad gas theory. What else could it be?
If anyone has had any experience with this sort of thing, I could really use the advice. Since no codes are being tripped, my next step is to change the plugs and wires, unless informed otherwise. <img src="images/icons/confused.gif" border="0">
Thanks!!!
02-08-2002, 10:15 PM
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Re: Engine Detonation??? Sorry to say, not that many yet... as far as the engine goes anyway!
Engine Mods:
-fast toys cold air induction
-direct flow lid
-holley power shot air filter (did have k&n)
-flow tech cut out
-flow master exaust <img src="images/icons/rolleyes.gif" border="0">
-all the little free mods
Does that help?
Engine Mods:
-fast toys cold air induction
-direct flow lid
-holley power shot air filter (did have k&n)
-flow tech cut out
-flow master exaust <img src="images/icons/rolleyes.gif" border="0">
-all the little free mods
Does that help?
02-08-2002, 10:16 PM
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Re: Engine Detonation??? I'm in the same boat. The strange part...the first time I dynoed in July, the curve was as smooth as glass.
The second time, after yanking the MAF screen and switching to a Z06 exhaust, I'm seeing KR up to 5 deg from 5-6k. The car just simply feels lazy w/KR.
The second time, after yanking the MAF screen and switching to a Z06 exhaust, I'm seeing KR up to 5 deg from 5-6k. The car just simply feels lazy w/KR.
02-08-2002, 10:24 PM
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Re: Engine Detonation??? Yeah, its strange! A friend of mine dynoed his camero(base model) and got 312 hp and 326 torqe. The funny thing is, at the track I beat him. Its pretty even off the line, in fact he usually pulls a little, but I catch up and then start walking away from him. Go figure!
02-08-2002, 11:22 PM
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Re: Engine Detonation??? [quote]Originally posted by MOBE:
<strong>Sorry to say, not that many yet... as far as the engine goes anyway!
Engine Mods:
-fast toys cold air induction
-direct flow lid
-holley power shot air filter (did have k&n)
-flow tech cut out
-flow master exaust <img src="images/icons/rolleyes.gif" border="0">
-all the little free mods
Does that help?</strong><hr></blockquote>
Did you port your MAF? That could be a huge difference here.
Usually, detonation is a sign of running too lean and/or too much timing. The car will typically run too lean if you ported your MAF (computed misreads airflow), and you will get detonation. In RARE cases, detonation can also occur with merely a lid.
The fix - adjustment of fuel/air curves with LS1 edit (or the rare case of timing). The old fix was to use a MAF translator, but I cannot recommend that anymore because the computer can relearn around your MAFT settings and just get you right back in the same boat.
There have been some isolated cases of totally stock LS1s with the detonation problem. In that case, it is warranty time.
<strong>Sorry to say, not that many yet... as far as the engine goes anyway!
Engine Mods:
-fast toys cold air induction
-direct flow lid
-holley power shot air filter (did have k&n)
-flow tech cut out
-flow master exaust <img src="images/icons/rolleyes.gif" border="0">
-all the little free mods
Does that help?</strong><hr></blockquote>
Did you port your MAF? That could be a huge difference here.
Usually, detonation is a sign of running too lean and/or too much timing. The car will typically run too lean if you ported your MAF (computed misreads airflow), and you will get detonation. In RARE cases, detonation can also occur with merely a lid.
The fix - adjustment of fuel/air curves with LS1 edit (or the rare case of timing). The old fix was to use a MAF translator, but I cannot recommend that anymore because the computer can relearn around your MAFT settings and just get you right back in the same boat.
There have been some isolated cases of totally stock LS1s with the detonation problem. In that case, it is warranty time.
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02-09-2002, 02:50 PM
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Re: Engine Detonation??? Your air flow mods might be causing the lean condition. You say you have ruled out "bad" gas. What octane are you using now? You might try some hi octane gas to see how your car reacts.
