my header and y install

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Dec 8, 2010 | 11:38 AM

Z28-4Ever

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From: chicago area

my header and y install

i had my headers and y-pipe installed and the car tuned, just a question its loud under the hood, like really loud fans (now i know the fans can be running more because of the header install but why though, because its louder than when it was stock). then every time i shift there is a knocking/ rumbling noise under the car and it does it when slowing down in gear also. just want to know if its an easy fix

Dec 8, 2010 | 11:47 AM

joecar

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From: So.Cal.

The knocking under the car is the y-pipe hitting the tunnel just behind the transmission.

Without going to poly motor mounts, you may be able to reposition the y-pipe by pulling down on it while the clamps are loose, this will mean leaving the tunnel brace removed.

Dec 8, 2010 | 12:03 PM

ramairetransam

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From: Amsterdam Ny, the good part

how much do you feel the poly mounts in these cars , on my monte i have poly dogbones and you feel it only at idle

Dec 8, 2010 | 12:18 PM

Z28-4Ever

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so your saying to loosen the clamps pull down and that should fix the knocking when i shift, but id have to remove the brace?

Dec 8, 2010 | 04:45 PM

joecar

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Quote:

Originally Posted by Z28-4Ever

so your saying to loosen the clamps pull down and that should fix the knocking when i shift, but id have to remove the brace?

When you pull down on the exhaust it may now bang on the brace.

Dec 9, 2010 | 04:58 AM

omarrakeen

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do you mean hitting noises? like the y is banging to the car floor? i mean yea its normal to be louder due to thinner walls.

Dec 9, 2010 | 12:35 PM

Z28-4Ever

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Yea it sounds like its hitting but it had enough clearence, apprently where the y and the catback connect is positioned high into the driveshaft tunnel so its hitting