Question for ALL aftermarket cam guys > slight "rattling" at 2000 rpm
#1
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Question for ALL aftermarket cam guys > slight "rattling" at 2000 rpm
My TR220 cam is fairly mild compared to many of the cams out there now. And I can say, it is not as noisy (sewing machine) as some of the faster ramp cams being used, but still has more valvetrain noise than when it was stock.
Now, my question: When the engine is hot and run up to about 2,000 rpm in neutral (no load), I notice a "rattling" sound in the engine. By about 2,500 rpm, the rattling seems to go away.
This rattling sounds a little different than the normal "fast ramp" valvetrain noise at idle. Kinda sounds like a timing chain rattling around, but the chain is new.
BTW, the lifter preload is dead-on and it burned no oil in the 1,800 highway miles I just put on it.
Anyone else have this rattling noise?
Thanks,
Ron
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<small>[ March 02, 2003, 06:43 PM: Message edited by: Kimchee and Rice ]</small>
Now, my question: When the engine is hot and run up to about 2,000 rpm in neutral (no load), I notice a "rattling" sound in the engine. By about 2,500 rpm, the rattling seems to go away.
This rattling sounds a little different than the normal "fast ramp" valvetrain noise at idle. Kinda sounds like a timing chain rattling around, but the chain is new.
BTW, the lifter preload is dead-on and it burned no oil in the 1,800 highway miles I just put on it.
Anyone else have this rattling noise?
Thanks,
Ron
_________________________________________________
<small>[ March 02, 2003, 06:43 PM: Message edited by: Kimchee and Rice ]</small>
#2
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Re: Question for ALL aftermarket cam guys > slight "rattling" at 2000 rpm
BTW, I think this is just another good reason to get the knock sensors de-sensitized a little when I get some PCM tuning done to the car. God only knows how much timeing retard we are all getting with these noisier valvetrains. <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" />
Ron,
Ron,
#3
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Re: Question for ALL aftermarket cam guys > slight "rattling" at 2000 rpm
mine rattles from 1300-2500 or so and my ramps are a lot slower then yours. With the same cam and SLP 1.25 straight vlave springs it was much quieter then the 918s on these heads for some odd reason. Maybe all the oil in the intake ports of the original heads dampened the sound <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> Sometimes I could swear its coming right from behind the water pump but I dont pay attention. I have a stock exhaust and cats on the car and it isnt really that noisy..
I was under the impression that the pcm will 'learn out' constant noise from 'normal' engine sources. At least according to the C5 service manual they do but I didnt read into it too deeply or worry about the noise since my car never sees 2500rpm or less at WOT and by that time its pretty quiet..
<small>[ March 02, 2003, 11:04 PM: Message edited by: kp ]</small>
I was under the impression that the pcm will 'learn out' constant noise from 'normal' engine sources. At least according to the C5 service manual they do but I didnt read into it too deeply or worry about the noise since my car never sees 2500rpm or less at WOT and by that time its pretty quiet..
<small>[ March 02, 2003, 11:04 PM: Message edited by: kp ]</small>
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Re: Question for ALL aftermarket cam guys > slight "rattling" at 2000 rpm
</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Kimchee and Rice:
<strong> BTW, I think this is just another good reason to get the knock sensors de-sensitized a little when I get some PCM tuning done to the car. God only knows how much timeing retard we are all getting with these noisier valvetrains. <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" />
Ron, </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I'm running the 224 XE-R cam on a 112lsa, The valvetrain is quite noisy and I have a poly trans mount. I have zero Knock Retard.
<strong> BTW, I think this is just another good reason to get the knock sensors de-sensitized a little when I get some PCM tuning done to the car. God only knows how much timeing retard we are all getting with these noisier valvetrains. <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" />
Ron, </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I'm running the 224 XE-R cam on a 112lsa, The valvetrain is quite noisy and I have a poly trans mount. I have zero Knock Retard.
#6
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Re: Question for ALL aftermarket cam guys > slight "rattling" at 2000 rpm
Thanks for the response folks...
Well, I guess it's just the nature of the beast.
Well, I guess it's just the nature of the beast.